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HP 6621A User's Manual

1. 3 4 5 exter Local Control Of System Functions The System Function keys consist of the ADDR ERR STO and RCL keys as shown in Figure 6 1 These keys are independent of the output selected and are used in setting the supply s HP IB address displaying error messages and storing recalling voltage and current settings for all of the supply s output channels Setting the Supply s HP IB Address As described on page 39 before you can operate the supply remotely you must know its HP IB address You can find this out locally from the front panel by pressing 86 Local Operation The supply s present address will appear in the display Address 5 is the factory set address If you want to leave the address set at 5 you can return to the metering mode by pressing the METER key or you can press another function key If you want to change the address you can enter a new value Any integer from 0 through 30 can be selected For example you can change the address of your supply to 10 by pressing Lo Displaying Error Messages The power supply can detect both programming and hardware errors Upon detecting an error the ERR annunciator on the front panel comes on and the ERR bit in the serial poll register will be set see page 75 When an error is detected you can display the error message by pressing the ERR key The power supply will return the error message to the display and clear the error bit For example if you program a
2. Do not attempt internal service or adjustment unless another person capable of rendering first aid and resuscitation is present DO NOT EXCEED INPUT RATINGS This instrument may be equipped with a line filter to reduce electromagnetic interference and must be connected to a properly grounded receptacle to minimize electric shock hazard Operation at line voltages or frequencies in excess of those stated on the data plate may cause leakage currents in excess of 5 0 mA peak SAFETY SYMBOLS Instruction manual symbol the product will be marked with this symbol when it is necessary for the user to refer to the instruction manual refer to Table of Contents Indicates hazardous voltages Indicate earth ground terminal E ral The WARNING sign denotes a hazard It calls attention to a procedure practice or the like which if not correctly performed or adhered to could result in personal injury Do not proceed beyond a WARNING sign until the indicated conditions are fully understood and met The CAUTION sign denotes a hazard It calls attention to an operating procedure or the like which if not correctly CAUTION performed or adhered to could result in damage to or destruction of part or all of the product Do not proceed beyond a CAUTION sign until the indicated conditions are fully understood and met DO NOT SUBSTITUTE PARTS OR MODIFY INSTRUMENT Because of the danger of introducing additional hazards do not install substitute parts
3. If it is not required to trip the OV with a TTL signal then a bias supply switch current limiting resistor R2 and protection diode are all that are required Note that with the unit off ac power removed the OV and OV terminals are inactive 52 Output Connections and Operating Information MINIMUM CIRCUIT BIAS y OPTIONAL PANIC BUTTON SWITCH OR RELAY CONTACTS See x 2N2995 GSMA y 9 0V TERMINAL pe TERMINAL OR EQUIVALENT BIRS Figure 4 8 External Trigger Circuit The internal equivalent OV circuit is shown in Figure 4 9 Note the internal DC blocking capacitor bleed resistor and noise bypass capacitors CAUTION Do not exceed 50 volts maximum between the OV and the OV terminals The OV terminals are rated at 240 Vdc including external OV voltage from chassis ground or any other output terminals POWER SUPPLY Figure 4 9 Equivalent Internal OV Trigger Circuit Output Connections and Operating Information 53 Power Supply Protection Considerations Battery Charging If you are using your supply in a battery charging application it is recommended that a series protection diode be added to prevent damage to the supply during an overvoltage shutdown Remember that each output has an overvoltage protection circuit that fires a crowbar to disable the output for any of the OVERVOLTAGE conditions described in Protection Features page 44 Figur
4. V terminal more positive than the V terminal This voltage will be I maximum at the rated current of the output See Figure 4 2 for reverse diode characteristic Note that when an output conducts through this diode it will indicate CC mode even though it is not regulating the current or voltage Also note that the voltage readback is not specified to indicate negative voltages although it will operate down to a limit of about 22 V on the low voltage outputs and 52 V on the high voltage outputs These values will still be indicated even if the actual voltage is more negative OUTPUT 2 SENSE JUMPERS REMOVED olkigigelelelo HO OUTPUT 1 v TO S SENSE JUMPER INSTALLED Figure 4 14 Series Connections with Remote Sensing Remote Sensing If it is necessary to remote voltage sense at the load connect the sense leads of output 1 and output 2 as shown in Figure 4 14 Note that the sense lead of output 2 must remain connected to the sense terminal of output 1 The outputs may be set as previously described Additional information on programming outputs connected in series is given in Appendix B Specifications for Series Operation Specifications for outputs operating in sense can be obtained from the specifications for single outputs Most specifications are expressed as a constant or a percentage or ppm plus a constant For series operation the percentage portion remains unchanged w
5. when the power supply is turned on For on off 1 all outputs will be on when the power supply is turned on Queries whether the specified output channel is turned on or off see page 71 The response is either 1 on or O off The front panel will display the message DISABLED when the selected output channel is turned off Sets the overvoltage trip point for the specified output channel see page 71 Causes the specified output channel to go through the overvoltage calibration routine see Appendix A Attempts to reset the overvoltage crowbar circuit in the specified output channel see page 71 Queries the present overvoltage setting of the specified output channel see page 71 The response is a real number Enables power on service request SRQ On off equals 1 causes the power supply to generate a service request when power is applied see page 77 On off equals 0 disables the PON SRQ The on off setting is retained in the supply s memory through interruption of ac line power Queries the present state of the power on SRQ function see page 77 The response is either 1 on or O off Recalls the voltage and current settings for all output channels from the specified internal register 1 to 10 These settings were previously stored using the STO command RCL programs all output channels in sequential order 1 2 3 4 to these stored settings see page 72 Queries the revision date of the power supply s firmware
6. 13 of nominal line voltage Frequency Range 47 66 Hz Note At low line the supply will operate with up to 3 4 Q line resistance General Information 17 Table 1 3 Supplemental Characteristics 40 W Low Voltage Outputs Temperature Coefficient Voltage 60 ppm 0 4 mV C Current 160 ppm 0 2mA C OVP 130 ppm 1 mV C Readback Temperature Coefficient Voltage 40 ppm 0 3 mV C 10mV Current 85 ppm 0 25 mA C 3 mA Current 95 ppm 0 3 mA C 3 mA 40 W High Voltage 60 ppm 1 mV C 160 ppm 0 1 mA C 130 ppm 2 mV C 40 ppm 0 7 mV C 23 mV 85 ppm 0 1 mA C 1 mA 95 ppm 0 1 mA C 1 2 mA 80 W Low Voltage 60 ppm 0 4 mV C 160 ppm 0 4mA C 130 ppm 1 mV C 40 ppm 0 3 mV C 10mV 85 ppm 0 5 mA C 5 mA 95 ppm 0 6 mA C 6 mA 80 W High Voltage 60 ppm 1 mV C 160 ppm 0 2 mA C 130 ppm 2 mV C 40 ppm 0 7 mV C 23 mV 85 ppm 0 2 mA C 2 mA 95 ppm 0 2 mA C 2 3 mA Long Term Drift In an 8 hour period following a 30 minute warmup 0 012 1 mV 0 032 2 mA 0 012 1 mV 0 032 2 mA 0 012 1 mV 0 032 4 mA 0 012 1 mV 0 032 4 mA Voltage Current Short Term Drift Within 30 minutes after a line and or load change Voltage 0 042 2 mV 0 042 2 mV 0 042 2 mV 0 042 2 mV Current 0 11 4 mA 0 11 4 mA 0 11 8 mA 0 11 8 mA Programmabl
7. 255 amp CHR 75 140 IF Err THEN 150 PRINT POWER SUPPLY PROGRAMMING ERROR 160 END IF 170 SELECT Err 180 CASE 0 190 PRINT NO ERROR OCCURRED 200 SUBEXIT 210 CASE 1 220 PRINT INVALID CHARACTER 230 CASE 2 240 PRINT INVALID NUMBER 250 CASE 3 260 PRINT INVALID STRING 270 CASE 4 280 PRINT SYNTAX ERROR 290 CASE 5 300 PRINT NUMBER OUT OF RANGE 310 CASE 6 320 PRINT DATA REQUESTED WITHOUT QUERY 330 CASE 7 340 PRINT STRING EXCEEDS DISPLAY LENGTH 350 CASE 8 360 PRINT NUMBER TOO LARGE FOR INPUT BUFFER 370 CASE 28 380 PRINT INVALID CHARACTERS IN STRING 390 CASE ELSE 400 PRINT UNRECOGNIZED ERROR NUMBER Err 410 END SELECT 420 PRINT RE ENTER STATEMENT AND TRY AGAIN 430 SUBEND Programming with a Series 200 300 Computt 1 LINE 10 Assigns the I O path name to the power supply LINE 20 Declare a common block for the I O path name LINE 30 Define interrupt on softkey depression and branch to error routine LINE 40 Idle on softkey definition LINE 80 Define subprogram Err_trap LINE 90 Disable interrupt capability while processing LINE 100 Bring in the common block for the I O pathname LINE 110 120 Enter error code from power supply LINE 130 Clears computer screen LINE 140 150 If an error occurred print message LINE 170 420 Print message based on error code Prompt user to try again If no error occurred print message saying no error occurred Stored Operatin
8. 31 Normal Self Test Indications ccecccecsssccceeeeneecceennceeceseeeeeeeeeeceenneeeceeneeeeeceseeeeeneaeeesesnaeeeeseneeeeeeeas 35 Self Test Errorssiccciicdcveisesicaeitentcdevduetecsyice ve davdeel odes dius ivscdee cde yachacenyacdb chan decacduuddesedetdepveden desbede io 36 Checking Out Your Supply Using Local Control eee eeeeesceeescneeseseecsseeesseeceseeeesaeecseeessseessseeeesaeeesaeees 36 Voltage Tests anat 37 Overvoltage Leticia rial EE EEE ETEA EE Sve dau cia UI ridad DES 37 Current Testiuvanitanidamindatan ae ei ieee denied dad 37 Introduction To Remote Operation eeecssseesseesssceceseecsseeeesseecsaeecscecsseecessaeesaeecsaeessseesesaeeesaeeesaeers 38 Enter Output Statements ica tddi 38 Reading the HP IB AddresSS coocconno sietst rean easan EEE EEE eaaa A aE e EE AEE ER ESA AA aA 39 Changing the HP IB Addr sS 0 aiii n r a E ria 39 A AAA 39 Getting Data from the Supply ccieiccanaa ida sa Savane 40 Often Us COMME A RRN ai 40 Returning the Supply to Local Mode eee eee eeeeceesseeesseecssecesseeceseecesaeeesaeecsaeecseeceseesesaeeesaeessaeesseessea 42 Output Connections and Operating Information Intr d ctiom A RI ba aid 43 Output Ranges OS ORO AE Sheba E eh gis E e 43 Operatin Qu drantS sirenenet ae la inte spot ete wesbevensvens 44 Range Select iniciara eves Ahi aad ak 44 Protection ESAS cia ited ca covey Hee raat oak Goch cae A AA Sak A A 44 Connecting The Loads stancsian erat dieting aie
9. 32 Display On Off When the display is on the commands sent across the HP IB may experience a slower processing time because the processor must also spend time to monitor the outputs and update the display You can shorten your command processing time by turning off the display To turn off the display send the command DSP 0 To re enable the display send the command 78 Remote Operation DSP 1 You can also find out the status of the display by sending the following query and addressing the supply to talk DSP The response will be either a 1 or a 0 Message Display Capability The display command can also be used to display messages on the front panel Messages may consist of a maximum of twelve alphanumeric characters Only upper case alpha characters numbers and spaces will be displayed For example to display the message OUTPUT 2 OK send the following command DSP OUTPUT 2 OK NOTE The BASIC programming statement for a series 200 300 computer would be as follows OUTPUT 705 DSP OUTPUT 2 OK Other Queries In the examples discussed above you saw how to use queries for each function discussed The following paragraphs describe other queries which were not previously covered ERROR Query The power supply can detect both programming and hardware errors You can use either the front panel see page 87 or the HP IB to find out the type of error Upon detecting an error the error annunciator on the front panel
10. 37 6 33 2 0 0016 30 Cross Section Q m meters Area in mm 0 5 0 0401 0 75 a 0 0267 1 0 0200 1 5 a 0 0137 2 5 0 0082 Notes 1 Ampacities for AWG wires are derived from MIL W 5088B Maximum ambient temp 55 C Maximum wire temp 105 C 2 Ampacities for metric wires are derived from IE Publication 335 1 3 Ampacity of aluminum wire is approximately 84 of that listed for copper wire 4 Because of wire inductance considerations it is recommended that you keep your load leads twisted tie wrapped or bundled together and less than 50 feet 14 7 meters in length per lead 5 See pages 47 amp 48 for information on wire gauge considerations with capacitive loads NOTE To prevent tripping of the overvoltage circuit pick a wire size sufficient to handle the FULL output current of the unit no matter what the intended load current or current limit setting Table 4 1 lists the resistivity for various wire sizes and the maximum lengths to limit the voltage drop to 1 0 volts for various currents NOTE The OVP circuit senses at the main output terminals and not on the sense leads Thus the voltage sensed by the OVP circuit could be as much as 2 V higher than the voltage being regulated at the load Program the OVP trip voltage accordingly when using remote sensing In addition if the voltage drop exceeds 1 5 V on either load lead a protective circuit will fire the OVP circuit regardless of the OVP setting Load le
11. Computt63 LINE 10 Assigns the I O pathname to the power supply LINE 20 30 Enter the operating voltage and current limit point LINE 40 Sets C equal to one half of the current limit point LINE 50 70 Determines the voltage setting for output 2 It is 20 2 V when the operating voltage is greater than 7 V 7 07 V when the operating voltage is between 7 V and 2 5 V and the same as the operating voltage below 2 5 V LINE 80 Clears the supply sets the current of output to one half of the current limit point and sets the voltage of output 1 to the operating voltage LINE 90 Sets the current of output 2 to one half of the current limit point and sets the voltage of output 2 to the value determined by the operating voltage LINE 100 Waits 1 second before reading back output voltage and current LINE 110 160 Reads the output voltage of output 1 and the output current of outputs 1 and 2 LINE 170 Prints the output voltage of the parallel outputs on the screen LINE 180 Prints the total output current of the parallel outputs on the screen Note that this is the sum of the output currents of outputs 1 and 2 Programming Outputs Connected In Series To program outputs connected in series you must first determine the maximum voltage and current that you would like to have available to your load These values are the desired voltage limit and current limit points Next program the current of both outputs to this desired current limit p
12. On Your Supply The following paragraphs describe the power on sequence which includes a self test of most of the power supply s circuits Before you turn on your supply make sure that e The line module on the rear panel is set to match your input line voltage Getting Started 31 e The proper fuse is installed and the line cord is plugged in If you have any questions concerning installation or power requirements review Chapter 2 To turn on your supply press the front panel LINE switch When the power is initially applied the supply performs a series of self tests which last about 3 seconds Included in these tests are checks of circuits on the HP IB board and on each of the output boards Z ETT 6624A SYSTEM DC a Figure 3 1 HP 6624A Front Panel Table 3 1 Controls and Indicators Returns power supply to local mode unless local lockout has been received via HP IB Also turns the power supply s display on if it was turned off via the HP IB HP IB Status Annunciators RMT Indicates that the power supply is operating under These three annunciators remote control HP IB indicate the HP IB status of the power supply ADDR Indicates that the power supply is addressed to talk or to listen SRQ Indicates that the power supply is requesting service 32 Getting Started Tab
13. Ps Ps 30 IF FNCv_mode THEN 40 PRINT OUTPUT IS IN CV MODE 50 END IF 60 END 70 80 90 DEF FNCv_mode 100 COM Ps Ps 110 OUTPUT Ps STS 1 120 ENTER Ps Sts 130 RETURN BIT Sts 0 140 FNEND Line 10 Assigns the I O path name to the power supply Line 20 Declare a common block for the I O path name The COM statement must be used for the Ps variable to preserve its value in the function subprogram Line 30 40 50 If FNCv_mode is true print the message Line 90 Defines the Cv_mode function Line 100 Brings in the common block for the I O pathname Line 110 120 Reads the present status of output into the variable Sts Line 130 Returns the value of bit position O of Sts Service Request and Serial Poll The fault and mask registers when used in conjunction with the service request and serial poll functions allow you to select which conditions can cause computer interrupts The fault and mask registers can also be used independently of the serial poll or service request if so desired The following example shows how to enable an interrupt to the computer in the case of an overvoltage condition After the interrupt has occurred this example includes an interrupt routine that conducts Programming with a Series 200 300 Compute99 a serial poll to determine on which output the overvoltage occurred Note that this example assumes that terminal block external OV trip lines are not wired together 10 ASSIGN Ps TO 70
14. Range 0 20 V 0 2 A 0 50 V 0 0 8 A 0 20 V 0 4 A 0 50 V 0 2 A Load Effect Regulation When remote sensing add 1 mV to the value listed for each 200 mV drop in the V load lead Voltage 2mV 2mV 2mV 2mV Current 1 mA 0 5 mA 2 mA 1 mA Source Effect Voltage 0 01 1 mV 0 01 1 mV 0 01 1 mV 0 01 1 mV Current 0 06 1 mA 0 06 1 mA 0 06 2 mA 0 06 2 mA Programming Accuracy At calibration temperature 5 C Note The programming accuracy specifications may degrade slightly when the unit is subjected to an RF field equal to or greater than 3 volts meter Voltage 19 mV 0 06 50 mV 0 06 19 mV 0 06 50 mV 0 06 Current 100 mA 0 16 20 mA 0 16 100 mA 0 16 40 mA 0 16 OVP 200 mV 0 13 475 mV 0 13 200 mV 0 13 475 mV 0 13 Readback Accuracy At calibration temperature 5 C Voltage 20 mV 0 05 50 mV 0 05 20 mV 0 05 50 mV 0 05 Current 10 mA 0 1 4 mA 0 1 20 mA 0 1 8 mA 0 1 Current 25 mA 0 2 8 mA 0 2 50 mA 0 2 20 mA 0 2 Load Transient Recovery Time 75 uS maximum to recover to within 75 mV of nominal value following a load change within the range 300 mA to full load for low voltage units and 150 mA to full load for high voltage units Maximum Output Noise PARD CV peak to peak 3 mV 20 Hz 20 MHz CV rms 0 5 mV 20 Hz 10 MHz CC rms 20Hz 10 MHz AC Input Voltage and Frequency Nominal Line 100 120 220 or 240 Vac Amplitude 6
15. See Service Manual Sets the causes for generating SRQ Setting can be 0 1 2 or 3 as described on page 76 Indicates that the command can be executed from the front panel Command Summat 7 Table C i Command Summary continued Queries the present setting of the reasons for issuing an SRQ see page 76 Response is 0 1 2 or 3 that corresponds with the SRQ lt setting gt described previously STO lt reg gt Stores the present voltage and current settings for all output channels in the specified register 1 to 10 see page 72 These settings can be recalled when desired see RCL command STS lt ch gt Queries the present status of the specified output channel The response integer 0 255 represents the sum of the binary weights of the status register bits see page 74 Causes the power supply to perform a self test of its HP IB interface The response Is 0 if the test passes or an integer failure code see Test Query page 79 VDATA lt ch gt lt Vlo gt lt Vhi gt Sends data to calibrate the voltage setting and readback circuits of the specified output channel Vlo and Vhi are measured values which the supply uses to calculate correction constants see Appendix A Causes the voltage of the specified output channel to go to the high calibration point see Appendix A VLO lt ch gt Causes the voltage of the specified output channel to go to the low calibration point see Appendix A VMUX lt ch
16. Table 5 5 The mask register which is set by the user is used to specify which bits in the status register are enabled unmasked to set bits in the fault register A bit is set in the fault register when the corresponding bit in the status register changes from 0 to 1 and the corresponding bit in the mask register is a 1 Also if a bit in the status register is already set and then the corresponding bit in the mask register is set unmasked the corresponding bit in the fault register will be set In addition if both status and mask register bits remain set after the fault register was read and cleared the fault register will remain cleared as long as there are no changes in either the status or mask registers with the following exception Executing a VSET ISET RCL OVRST OCRST or OUT on off command will cause the CV CC CC or UNR bit as applicable in the fault register to be set Note that the fault register is cleared immediately after it is read As shown in Figure 5 3 if one or more bits in the fault register of a given output channel are set then the FAU bit for that output in the serial poll register will also be set and a service request may be generated see page 76 To read the fault register of output 2 and find out which bits are set send the following query and address the supply to talk FAULT 2 The power supply responds with a number which can be decoded from Table 5 5 For example the number 9 8 1 ind
17. a a o 2 Z Q 3 u e 3 a 2 un lia W E lr LL L u a e 104H SOH 1004H S5004H imH 5mH 10mH INDUCTANCE x SMALL SIGNAL OVERSHOOT DURING CURRENT PROGRAMMING Figure 1 6 CC Operation with Inductive Load Small Signal Stability Graph for LV 0 to 20 V Outputs General Information 23 OUTPUT OUTPUT IMPEDANCE IMPEDANCE OHMS OHMS iK 40K ik 10K FREQUENCY Hz FREQUENCY Hz 40W HV O 50V OUTPUT 40W LV O 20V OUTPUT FREQUENCY Hz FREQUENCY Hz 80W LV O 20V OUTPUT BOW HV O 50V OUTPUT Figure 1 7 Output Impedance Typical Graphs See Supplemental Characteristics Table 1 1 24 General Information Installation Introduction This chapter contains instructions for checking and mounting your power supply connecting your supply to ac power converting it from one line voltage to another and connecting the HP IB cable The power supply generates operating magnetic fields which may affect the operation of other instruments If your instrument is susceptible to magnetic fields do not locate it in the immediate vicinity of the power supply Typically at three inches from the power supply t
18. affect the entire power supply cannot query or change the address remotely over the and are independent of the HP IB output selected ERR Displays a programming or hardware error message and clears the ERR bit in the serial poll register STO Used in conjunction with the numeric entry keys to store the present output voltage and current settings for all outputs in the specified internal register 1 to 10 Each register contains voltage and current settings for all output channels RCL Used in conjunction with the numeric entry keys to recall the settings from the specified internal register 1 to 10 All outputs are set to the recalled values Getting Started 33 Table 3 1 Controls and Indicators continued Output Control Keys OUTPUT SELECT Selects one of the output channels These twelve keys are for local control or display This key allows the channels output dependent to be selected in forward or reverse 0 sequence VSET Displays the selected output s present voltage setting The setting can be changed using the numeric entry keys ISET Displays the selected output s present current setting The setting can be changed using the numeric entry keys OUTPUT ON OFF Toggles the selected output on and off When off DISABLED appears on the display OVSET Displays the selected output s overvoltage trip point The setting can be changed using the numeric entry keys OVRST Resets
19. connected through relay or switch contacts contact bounce may activate the overvoltage circuit and shut down the supply Therefore it is recommended that the output be downprogrammed to 0 or turned off disabled before the relay or switch contact is opened or closed Positive and Negative Voltages Either positive or negative voltages can be obtained from the supply by grounding or commoning one of the output terminals Always use two wires to connect the load to the supply regardless of where or how the system is grounded This supply can be operated with any output terminal 240 Vdc including output voltage from ground Remote Voltage Sensing Because of the unavoidable voltage drop developed in the load leads the as shipped terminal block strapping pattern shown in Figure 4 4 does not provide the best possible voltage regulation at the load The remote sensing connections shown in Figure 4 5 improve the voltage regulation at the load by monitoring the voltage there instead of at the supply s output terminals This allows the power supply to automatically compensate for the voltage drop in the load leads Remote Output Connections and Operating Information 49 sensing is especially useful for CV operation with load impedances that vary or have significant lead resistance It has no effect during CC operation Because sensing is independent of other power supply functions remote sensing can be used regardless of how the power supply
20. oaks RN 58 Specifications for Series Operation cc eeeeeesecsseecssecesseecesseecsaeecsseecsseecesaeeesaeecseessseesesseeesaeessneeeeea 58 Remote Operation TOUCH da EO 61 HP IB Opera asin 61 Interface Fun A OA 61 SER A NAS 62 Power On Service Request PON cccsssscceeseneeceeeneseeceseeeceseaeeeceseneeecseacaeesseaeeeeeeeaeeceeeaeeeeseneeeeeeeas 63 Programming Staind aa dared ea 63 Numeric Data vce ti 63 Order of Execution scicccccisvidiie Wien deristid evista E S e cda E decis donde 68 TELMO Op ile le n delia 68 Initial ConditiOOS ii a idas 68 Power Supply Commands unan dde 68 Voltage Programming colirio de 69 Current Pros aminino ento seese balay destedevng vast ae a sang ite uns ones eaa aenea s sang had ranana eea patna secon gs 69 Range SwitChing aca 70 NN O EE cots savtsteeshen eat snstetens 71 Overvoltage Protections c cc jisten t diia 71 Overcurrent Protect oN n rrene repune ea panee Ea iea eaea A Esee Muvecenstadetevruye conta doves di dd le ias 72 Multiple Output Storage and Recall ces eeeesecsseecsseecesceeesseeeceecsseecsseeessseeesaeecseesseeessseeeesaeeesaeers 72 ThE Cl ar COMMON AA AAA is 73 Stat s REPOrting cuidada rinitis iaa 73 AN AE AAA seep e dhe tes beng neie ep Neea edut sens Ee e ENERE aE Eee n oR Enae 76 Reprogrammins Deluca a E EE Se eats E A 78 Display OILO i PARA AE A E A E EE E E EE 78 Oth r Queries cuina e E e E e r ia 79 Local Operation TITO UCM it a and Suet NEERA E
21. or CV condition to appear as faults i e set the corresponding bits in the fault register Note that the mask register does not affect the status register it simply determines which bits in the status register can set bits in the fault register When you press the FAULT key the contents of the fault register are displayed For example the display 9 indicates that the OV and CV bits in the fault register are set The fault register is cleared immediately after it is reset by pressing FAULT Setting the Reprogramming Delay A power supply s output may switch modes momentarily after a new output value is programmed or the output is reset from zero To prevent these momentary conditions from appearing as faults each output has a reprogramming delay parameter The delay parameter specifies a time period in which the CV CC CC and UNR bits in the present status register are masked from the fault register and from the overcurrent protection OCP circuit after certain commands are sent Refer to Reprogramming Delay page 78 for additional details about the reprogramming delay parameter The delay time is initiated following a VSET ISET OVRST OCRST OUT on off or RCL command that is sent from the front panel or from a remote controller The delay time is settable from 0 to 32 seconds in 004 s 4 ms intervals The default or power on value is 20 ms For example set the delay time of the selected output to 345 mS by pressing ory
22. or perform any unauthorized modification to the instrument Return the instrument to a Hewlett Packard Sales and Service Office for service and repair to ensure that safety features are maintained Instruments which appear damaged or defective should be made inoperative and secured against unintended operation until they can be repaired by qualified service personnel SAFETY SUMMARY continued GENERAL Any LEDs used in this product are Class 1 LEDs as per IEC 825 1 ENVIRONMENTAL CONDITIONS This instrument is intended for indoor use in an installation category II pollution degree 2 environment It is designed to operate at a maximum relative humidity of 95 and at altitudes of up to 2000 meters Refer to the specifications tables for the ac mains voltage requirements and ambient operating temperature range SAFETY SYMBOL DEFINITIONS Direct current Terminal for Line conductor on permanently installed equipment Alternating current A Caution risk of electric shock Both direct and alternating current A Caution hot surface Three phase alternating current NN Caution refer to accompanying documents Earth ground terminal Protective earth ground terminal MN Out position of a bi stable push control In position of a bi stable push control Frame or chassis terminal On supply Off supply Terminal for Neutral conductor on permanently installed equipment Terminal is at earth potential c Standby supply Used for mea
23. percentage of setting plus a constant Short Term Drift Maximum change of regulated output voltage or current within 30 minutes after a line and or load change Expressed as a percentage of setting plus a constant Output Noise PARD PARD replaces the former term ripple and noise PARD is the periodic and random deviation of dc output voltage or current from its average value over a specified bandwidth and with all influence and control quantities maintained constant General Information 15 Programming resolution Average programming step size Current Sinking Current Each output can sink as well as source current The sinking capability is not programmable and depends upon the output voltage The current sinking capability is described in greater detail in Chapter 4 VOLTAGE START VALUE MENE ESNE b PROGESSING TP Pe i TIME CONSTANT Figure 1 3 Output Response Characteristics 16 General Information Table 1 2 Specifications PERFORMANCE SPECIFICATIONS 0 to 55 C unless otherwise specified Outputs 40 W Low 40 W High 80 W Low 80 W High Voltage Voltage Voltage Voltage DC Output Ranges All outputs will accept voltage programming commands 1 higher than those listed and current programming commands 3 higher than those listed Also the minimum programmable current values are slightly above zero amps for each output See Table 5 4 Low Range 0 7 V 0 5 A 0 20 V 0 2 A 0 7 V 0 10 A 0 20 V 0 4 A High
24. power on and cleared when a CLR command is sent Service Request Generation When operating your supply you may want it to request service every time a fault or a programming error condition occurs To do this you send a service request SRQ command When the condition is true the power supply responds by setting the RQS bit in the serial poll register setting the SRQ annunciator on the front panel and issuing an SRQ over the HP IB The 662xA supplies can generate a service request for any of the following reasons refer to Table 5 7 e An Output Fault If there is a fault on one or more of the output channels and you previously sent the SRQ 1 or SRQ 3 command see Service Request Enable Disable information below then an SRQ will be generated e An Error If there is an error see Tables 5 8 and you previously sent the SRQ 2 or SRQ 3 command see Service Request Enable Disable information below then the supply will generate a service request e Power on At power on the PON bit of the serial poll register is set but the supply will only generate an SRQ if you previously sent a PON command e Input Line Voltage Dropout Same as power on condition To find out the nature of the service request you must do a serial poll This will isolate the output that generated the request by checking which of the FAU bits are set in the case of a fault or checking to see if the error bit is set in the case of an error If the SRQ on faults was se
25. range are 1 higher than the rated voltage and the maximum programmable current values for each range are 3 higher than the rated current 3 40 W High V 6624A 1 amp 2 40 W Low V 3 amp 4 40 W High V Low High Low High 6623A 1 Low 0 to 7 07 V 0 08 to 5 15 A 0 to 23 V 40 W Low V High 0 to 20 2 V 0 08 to 2 06 A 0 10 V 0 006 V 0 025 A 2 Low 0 to 7 07 V 0 13 to 10 30 0 to 23 V 80 W Low V High 0 to 20 2 V 0 13 to 4 12 A 0 10 V 0 006 V 0 050 A Low High Low High Low High Low High Each output channel wakes up with current programmed to a small positive value This permits the output channel s output voltage to be programmed up without specifically programming the current An output channel in fact cannot be programmed to zero amps If the output channel receives a command to go to zero amps or any positive current below the minimum programmable current it will set itself to the minimum Note that you can use the DCPON command to cause the ouput channels to wake up with the current programmed to a small negative value This prevents currrent overshoots at turn on if the unit is operating in constant current mode Range Switching Each output operates in the boundaries of either the low range or the high range as specified in Table 5 4 Refer to page 43 for a detailed description of the dual range operation The range is selected based on the programmed parameters If the last parameter voltage or current p
26. register will be reset to the zero voltage and minimum current settings of each output channel The advantages in using the internal registers are that command processing time is saved and repetitive programming of different settings is simplified The STO key can be used in conjunction with the OUTPUT ON OFF key to store settings while the outputs are disabled OFF These stored settings can be used later to program the outputs to the stored settings using the RCL and OUTPUT ON OFF keys Local Operation 87 Calibration Procedures Introduction This appendix discusses the software calibration procedures for the power supply These supplies should be calibrated annually or whenever certain repairs are made see Service Manual Because there are no internal or external hardware adjustments your power supply can be calibrated without removing the covers or removing it from the cabinet if it is rack mounted Calibration is performed by measuring actual output values and sending them to the supply over the HP IB The power supply uses these values to calculate output readback and overvoltage correction constants These correction constants are stored in a non volatile memory on the HP IB interface board of the supply Thereafter when a command such as VSET1 5 is sent to set the voltage on output 1 the power supply uses the correction constants to accurately program the output Correction constants for offset and full scale voltage and current
27. the selected output s overvoltage crowbar the cause of the overvoltage must be removed before reset is successful OCP Toggles the selected output s overcurrent protection circuit on and off OCRST Resets the selected output s overcurrent condition and returns the output to its previous settings the cause of the overcurrent must be removed before reset is successful METER Returns the display to the metering mode from any other mode e g VSET In the metering mode the measured output voltage and current of the selected output are displayed DLY Displays the reprogramming delay for the specified channel The setting can be changed using the numeric entry keys UNMASK Displays the present setting of the mask register for the specified channel The setting can be changed using the numeric entry keys FAULT Displays the contents of the fault register for the specified channel A bit gets set in the fault register when the corresponding bit is set in both the status and mask registers Pressing the FAULT key also clears the fault register 34 Getting Started Table 3 1 Controls and Indicators continued Numeric Entry Keys 0 to 9 Set the value of the specified function These keys are used in and conjunction with many of the e g VSET 16 550 System Control and Output Control keys to enter the lt backspace Erases the previous keystroke Depressing desired values into the power this key without
28. the voltage of the specified output to go to full scale value Take appropriate precautions The following general procedure applies to any computer that you are using to control your power supply This procedure must be repeated for each output on your power supply The calibration commands shown are the actual string commands that must be sent to the power supply Because the power supply will attempt to calibrate itself even when incorrect or invalid readings are sent to it it is recommended that you perform some type of error checking after steps 4 5 and 8 to ensure that the values sent to the supply are legitimate Use the ranges in Table A 2 as a guide If an error is detected while in calibration mode send CLR or turn the supply off to maintain the previous calibration constants This will prevent incorrect constants from being stored See Table 5 8 for a list of errors Before you continue with this procedure disconnect all loads from the supply strap the supply for local sensing and connect the voltmeter to the S and S terminals as shown in the voltage calibration setup of Figure A 1 Start with output channel 1 and use the following commands to calibrate your power supply Calibration Procedures 91 NOTE Do not turn the power supply off during the calibration procedures Otherwise the correction constants are not stored Exercise care when moving the leads 1 CMODE lt param gt This command turns the calibration mode eith
29. 0 180 Prompts the user to make voltage calibration connections and waits for CONTINUE key to be pressed LINE 200 Sets the voltage of the specified output to the high calibration point LINE 210 Sets the variable Vhi to the output voltage as measured by the user defined function FNDvm LINE 230 Sets the voltage of the specified output to the low calibration point LINE 240 Sets the variable Vlo to the output voltage as measured by the user defined function FNDvm LINE 260 Sends the measured data in volts to the power supply for the specified channel LINE 280 Checks the power supply for errors with the user defined function FNPs _ err If there was an error the program goes to the line labeled Finish and the supply is cleared The new measured data is not used and the previous calibration constants are maintained 94 Calibration Procedures LINE 300 Instructs the power supply to perform an overvoltage calibration on the specified channel LINE 310 330 Displays a message on the computer until bit 4 RDY of the power supply s serial poll register indicates that the supply is finished processing the OVCAL command This may take up to 10 seconds LINE 350 Checks for errors See line 280 LINE 370 380 Prompts the user to make current calibration connections and waits for CONTINUE key to be pressed LINE 400 Sets the current of the specified output to the high calibration point LINE 410 Sets the variable Ihi to the output current as
30. 008 312 255 9800 Hewlett Packard Company 5161 Lankershim Blvd No Hollywood CA 91601 818 505 5600 Hewlett Packard Company 2015 South Park Place Atlanta GA 30339 404 955 1500 Canada Hewlett Packard Ltd 6877 Goreway Drive Mississauga Ontario L4VIM8 416 678 9430 Australia New Zealand Hewlett Packard Australia Ltd 31 41 Joseph Street Blackburn Victoria 3130 Melbourne Australia 03 895 2895 Geneva Switzerland 41 22 780 8111 Far East Hewlett Packard Asia Ltd 89 Queensway Central Hong Kong 5 8487777 Japan Yokogawa Hewlett Packard Ltd 15 7 Nishi Shinjuku 4 Chome Shinjuku ku Tokyo 160 Japan 03 5371 1351 Latin America Latin American Region Headquarters Monte Pelvoux Nbr 111 Lomas De Chapultepec 11000 Mexico D F Mexico 525 202 0155 Middle East and Africa Geneva Switzerland 41 22 780 7111 For all other areas Hewlett Packard Company Intercontinental Headquarters 3495 Deer Creek Road Palo Alto CA 94304 U S A HP Sales and Support Office 115
31. 11 HDW ERR CH 3 Same as in Error 11 HDW ERR CH 4 Same as in Error 11 NO MODEL NUM The interface cannot find its model number There may be a hardware failure or the instrument may require reprogramming Service is required CAL ERROR You tried to use either a calibration command with CMODE off or the calibration failed while in CMODE Enable CMODE and check numbers sent during calibration Also there could be a hardware error UNCALIBRATED There is an incorrect checksum in the EEPROM possibly as a result of incorrect calibration procedure Recalibrate and if the problem persists your supply has a hardware failure Table 5 8 Error Messages continued CAL LOCKED Calibration was attempted with the Calibration Jumper on the HP IB board in the lockout position Reposition jumper if desired See Service Manual SKIP SLF TST The self test jumper on the HP IB board is in the Skip Self Test position No self test was done This is for diagnostics only See Service Manual Table 5 9 TEST Responses Explanation This is the response to the TEST query when there are no errors The timer has failed self test Refer to the troubleshooting section in the Service Manual The RAM has failed self test Refer to the troubleshooting section in the Service Manual The ROM has failed the checksum test Refer to the troubleshooting section in the Service Manual Remote Operation 81 Local Operation Introduction Chapter 3 introduce
32. 12 35 In scientific notation the letter E stands for 10 raised to For example 1 2E3 is read as 1 2 times 10 raised to the 3rd power which equals 1 200 Plus and minus signs are considered numeric characters and are optional If you program a number with an accuracy that is greater than the resolution of the supply the number will automatically be rounded to the nearest multiple of the power supply s resolution Table 5 1 gives the ranges for numeric data that is sent to the supply Remote Operation 63 The power supply will also return numeric data ASCII characters to your computer The format of the numbers returned depends upon the type of data requested Table 5 2 gives the format for data returned to the computer in response to any of the queries that are listed e HEADER D TERMINATOR Ea EADER NUMERIC DATA TERMINATOR pS TO ee O jie NUMERIC DATA TERMINATOR nO NUMERIC DATA NUMERIC DATA AEH TERMINATOR EO TERMINATOR o Figure 5 2 Sheet 1 of 2 Syntax Forms for Power Supply Commands 64 Remote Operation HEADER sr TERMINATOR O E O TT Be NUMERIC DATA KSP DIGIT ALSO CHANNEL I DIGIT O DIGIT Sr Opa TERMINATOR CARRIAGE RETURN ASCII 13 LINE F
33. 24A and 6627A Multiple Output System Power Supplies Block Diagram 14 General Information Specifications Table 1 2 lists the performance specifications for the HP 662xA power supplies Performance specifications describe the instrument s warranted performance The service manual Option 910 contains procedures for verifying the performance specifications Table 1 3 lists the supplemental characteristics for the HP 662xA supplies Supplemental characteristics are type tested or typical values which are based on a product sample and while representative are not guaranteed Qualifying Conditions All performance specifications apply over the full operating temperature range of the power supply 0 to 55 C unless otherwise specified All regulation accuracy etc specifications are plus or minus the values listed All measurements are made at the rear terminals of the supply with a resistive load and local sensing unless otherwise specified Voltage measurements are made from the S to the S terminals Overvoltage measurements are made from the V to the V terminals Current refers to the output acting as a current source while Current refers to the output acting as a current sink Definitions Load effect Maximum steady state change in the regulated output parameter due to a change in load resistance on the output in question Source effect Maximum steady state change in the regulated output parameter due to a change in the sou
34. 4m Do not stack more than three connector blocks together on any HP IB connector The resultant leverage can exert excessive force on the mounting panels Make sure that all connectors are fully seated and that the lock screws are firmly finger tightened Do not use a screwdriver Use a screwdriver only for the removal of the screws Installation 29 Getting Started Introduction This chapter is intended for the first time user of the supply It provides four main discussions Front Panel Controls and Indicators Turning on Your Supply Checking Out Your Supply Using Local Control Introduction to Remote Operation First the supply s front panel controls and indicators are briefly described Some of the controls and indicators will be used in the Turn On and Checkout procedures that follow Chapter 6 describes how to use all of the front panel controls Successful completion of the turn on and checkout procedures ensures with a high level of confidence that your supply is operating properly Complete performance testing and troubleshooting procedures are given in the Service Manual HP Part No 5957 6379 The checkout procedures are performed locally from the front panel In addition to checking the operation of your supply these simple step by step checkout procedures will help the first time user become familiar with operating the supply from the front panel When you have completed the checkout procedures you are then introduced to th
35. 5 20 COM Ps Ps 30 OUTPUT Ps CLR UNMASK1 8 UNMASK2 8 SRQ1 40 ON INTR 7 1 CALL Err _ trap 50 ENABLE INTR 7 2 60 OUTPUT Ps OVSET1 4 0VSET2 4 70 OUTPUT Ps VSET1 5 VSET2 5 80 Lbl GOTO Lbl 90 END 100 110 120 SUB Err _ trap 130 OFF INTR 140 COM Ps Ps 150 IF BIT SPOLL Ps 0 THEN 160 OUTPUT EPs OUT1 0 OVRSTI 170 PRINT OVERVOLTAGE ON OUTPUT 1 180 END IF 190 IF BIT SPOLL EPs 1 THEN 200 OUTPUT Ps OUT2 0 0VRST2 210 PRINT OVERVOLTAGE ON OUTPUT 2 220 END IF 230 OUTPUT Ps FAULT 1 FAULT 2 240 SUBEND LINE 10 LINE 20 LINE 30 LINE 40 LINE 50 LINE 60 LINE 70 LINE 80 Assigns the I O pathname to the power supply Declare a common block for the I O pathname The COM statement must be used for the Ps variable to preserve its value for use in the service routine Returns the power supply to its power on state unmasks output 1 s and output 2 s OV status bits to generate faults and enables the service request capability on all outputs Define interrupt at interface 7 with HP IB priority 1 Enable interrupt at interface 7 for service request type interrupts only Sets the overvoltage of outputs and 2 to 4 volts Sets the voltage of outputs and 2 above the OV setting so that both outputs will overvoltage when the program is run Waits for the computer to receive the interrupt This simulates conditions that would normally exist when a program is running LINE 120 Defines
36. 70 480 IF FNPs _ err lt gt 0 THEN Finish 490 500 OUTPUT Ps VSET Chan 0 ISET Chan 0 510 520 INPUT ANY MORE OUTPUTS TO CALIBRATE Y OR N X 530 IF X Y OR X y THEN Start_loop 540 550 OUTPUT Ps CMODE 0 560 570 Finish HERE WHEN DONE 580 OUTPUT Ps CLR 590 DISP END OF CALIBRATION PROGRAM 600 END 610 620 630 DEF FNDvm 640 COM Instr Ps Vm 650 WAIT 02 660 TRIGGER Vm 670 ENTER Vm Reading 680 RETURN Reading 690 FNEND 700 710 DEF FNPs _ err 720 COM Instr Ps Vrn 730 OUTPUT Ps ERR 740 ENTER Ps Err 750 IF Err lt gt 0 THEN PRINT POWER SUPPLY ERROR Err CORRECTION CONSTANTS NOT SAVED RESTART 760 RETURN Err 770 FNEND LINE 10 This comment line identifies the program as a CALIBRATION EXAMPLE LINE 30 40 Assigns I O path names to the power supply and the voltmeter LINE 50 Establishes a COM block for the instruments on the HP IB LINE 60 Initializes the variable Shunt _ resistor to 1 ohms LINE 80 Clears the power supply LINE 90 Initializes the voltmeter to take voltage readings LINE 100 110 Tells the voltmeter to take a reading and clears the voltmeters output buffer This reading is not used in the program LINE 120 Turns on the power supply calibration mode LINE 140 Labels the line Start_loop to loop back to when calibrating more than one output LINE 160 Enters the output channel number to be calibrated LINE 17
37. AD IEC 801 3 1984 EN 50082 1 1992 3 V m IEC 801 4 1988 EN 50082 1 1992 0 5 kV Signal Lines 1 kV Power Lines Supplementary Information The product herewith complies with the requirements of the Low Voltage Directive 73 23 EEC and the EMC Directive 89 336 EEC and carries the CE marking accordingly Note 1 The product family was introduced prior to 12 93 New Jersey January 1997 Location Date Bruce Krueger Quality Manager European Contact Your local Hewlett Packard Sales and Service Office or Hewlett Packard GmbH Department TRE Herrenberger Strasse 130 D 71034 Boeblingen FAX 49 703 1 14 3143 WHAT THIS MANUAL CONTAINS This is the Operating manual for the HP 6621A through 6624A and 6627A Series of Multiple Output Linear System Power Supplies It contains information relating to the installation operation and programming of these supplies as outlined below Maintenance and troubleshooting instructions are given in a separate Service Manual HP Part No 5957 6379 Chapter 1 General Information Chapter contains a general description of the power supplies as well as instrument specifications and information concerning options and accessories Chapter 2 Installation Procedures Chapter 2 contains information to prepare the supply for use Included in this chapter are power requirements line voltage conversion and HP IB interface connections Chapter 3 Getting Started Chapter 3 contains a brief descripti
38. EED ASCII 18 SPACE ASCII 32 HH DABA EOI OPTIONAL REPEAT OPTIONAL SKIP t CHARACTER IS A Z 8 9 5P gt e EOI IS CONCURRENT WITH LAST DATA BYTE DAB SENT Figure 5 2 Sheet 2 of 2 Syntax Forms for Power Supply Commands Remote Operation 65 Table 5 1 Power Supply Commands OUT Set the State of all DCPON 0 1 off on CC Outputs at Power On 2 3 off on CC UNMASK 1 2 3 4 0 255 Reprogram Delay DLY 1 2 3 4 0 32 LSB 0 004 in seconds Reset Overvoltage OVRST 1 2 3 4 OCRST 1 2 3 4 Service Request SRQ o o 0 123 ell A AGO BE On Off Display On Off DSP fom ee up to 12 characters Store Settings STO d Tt c2_ Recall Settings RCD to c2_ Clear Supply MR EO a Output channels 3 and 4 are not used in all models see Table 5 4 C3 C4 C4 C4 C4 C3 C2 C2 C2 C2 C2 Cl Table 5 2 Power Supply Queries Note 7 Note 1 Notes 5 and 6 Fig 5 2 Voltage Setting VSET 1234 SZzDDDD 0 Q SZZD DD Note 2 see Table 5 4 O Q Voltage Output 1 2 3 4 SZD DDD e Q2 ee ee Note 3 See Table 5 4 Err ER D ZZD D ZZD Satt NE Ts J O AAA H Calibration Mode CMODE z _ oo S Sign Z Digit with leading zeros put out as spaces D Digit lt sp gt space Power On SRQ On Off PON ZZD Last stored value QI 66 R
39. GE OUTPUT 1 8Q W OUTPUT 1 SQW LOW VOLTAGE HIGH VOLTAGE HP 6621A HP_6622A OUTPUT 2 48W OUTPUT 2 BAN LOW VOLTAGE OUTPUT 4 40W LOW VOLTAGE HIGH VOLTAGE HIGH VOLTAGE OUTPUT 3 48W OUTPUT 1 40W OUTPUT 3 48 OUTPUT 1 4 W HIGH VOLTAGE LOW VOLTAGE HIGH VOLTAGE LOW VOLTAGE HIGH VOLTAGE HP 6623A HP 6624A HP 6622A Figure 4 1 Output Connections Output Connections and Operating Information 43 Operating Quadrants Figure 4 2 shows the operating locus of your power supply in three quadrants The area in quadrant 1 shows the operating locus defined by the voltage and current settings of each output The characteristics shown for quadrant 1 incorporate remote sensing and include the maximum available sense voltage plus load lead drop The area in quadrant 2 indicates the locus where each output can operate as a current sink You cannot program current limit values in quadrant 2 Figure 4 3 shows the current sink characteristics at voltages below 2 0 V in greater detail The area in quadrant 4 illustrates the reverse polarity diode characteristics of each output Do not operate any output with reverse voltage currents that are greater than the maximum rating of the output Notice that the L shaped characteristics in quadrant 1 of Figure 1 1 consists of two overlapping ranges a high voltage low current range and a low voltage high current range The power supply always limits its settings to within the boundaries of these ran
40. N 83 Local Modena E A A ESA E E e EE E G 83 Local Control Of Output FUNCTIONS ceeeseeesseeessceceececeeceeessaecsaeecsacecseecesaeecsaeecsaeeeseecesaesesseeesaeees 83 A O 83 Table Of Contents continued Setting Voltage ona daa aa Mi bedi ett 84 CHINE A A netsh tet eet 84 Enabling Disabling an Output eee eesccssceceseeeesseecsneecseesssecsseeeesseecsseecsneecssaeesssuecseesseeseneeeenaes 85 Setting Overvoltage ProtectiOn escceecssscecsseceeseeesseecsseecsscecsscecesaesesaeecsseesseecseeeceaeecsaeessaeessneesses 85 Resetting Overvoltage ProtectiON ooooccnoo aritgin anr enra E E p aari 85 Enabling Disabling Overcurrent Protection ceesesesecsseecsseecessaecsseecsacessseecssaeeesaeecsaeerseeesseeeesaes 85 Resetting Overcurrent ProtectiON ooooccnnnno inn NE E E R EE E TETEE E S 85 Displaying the Contents of the Fault Regilster o ooonnonncnonccioncccnnancnonccnonacnonanonnnnonnnccnonccnnn no ronancnnn nono ccoo 85 Setting the Reprogramming Delay ooooocnnnno eeeescccssseeesseeceeecsscecsceeessaeeesaeecsaeesseeesseeseseeesaeessaeessseeesea 86 Local Control Of System FUNCtIONS esceeeeseeesseeesseecscecsseeceseeecsaeecsscecsseecesaeeesaeecsaaesseesssaeeesaeeesaeers 86 Setting the Supply s HP IB AddreSS ooooccno ccceeccessseeesseecseecssceceseecesaeeesaeecsaeesseecseeeessaeesaeessaeessaeessea 86 Displaying Error Messages at a lato load sia 87 Storing and Recalling Voltage and Current Settings for all
41. ONNECTING LOAD LEADS AND REMOTE SENSE LEADS CAPACITOR EQUIVALENT S ES RESISTANCE Figure 1 4 CV Operation with Capacitive Load Stability Graph for all Outputs General Information 21 ING AREA ABOVE LINES mI 4 10 CURRENT LIMIT OVERSHOOT Hi 30 CURRENT LIMIT OVERSHOOT L STABLE OPERATII 3 B savan OVOT SMd YOLONGNI OVO JO SONWLSISSY JALIA443 WLOL 500mH 1H 50mH O0OmH 5004H ImH 50uH 100pH INDUCTANCE SMALL SIGNAL OVERSHOOT DURING CURRENT PROGRAMMING Figure 1 5 CC Operation with Inductive Load Small Signal Stability Graph for HV 0 to 50 V Outputs 22 General Information STABLE OPERATING AREA ABOVE LINES 10 CURRENT LIMIT OVERSHOOT X 30 CURRENT LIMIT OVERSHOOT X 2 a A u J a 4 9
42. OPERATING MANUAL SYSTEM DC POWER SUPPLIES HP MODELS 6621A 6622A 6623A 6624A and 6627A HP Part No 5957 6377 HP Model 6621A Serials 3213A 01681 and Above HP Model 6622A Serials 3210A 02091 and Above HP Model 6623A Serials 3209A 02231 and Above HP Model 6624A Serials 3210A 06721 and Above HP Model 6627A Serials 3209A 00841 and Above For instruments with higher Serial Numbers a change page may be included Microfiche Part No 5957 6378 Printed in USA January 1993 CERTIFICATION Hewlett Packard Company certifies that this product met its published specifications at time of shipment from the factory Hewlett Packard further certifies that its calibration measurements are traceable to the United States National Bureau of Standards to the extent allowed by the Bureau s calibration facility and to the calibration facilities of other International Standards Organization members WARRANTY This Hewlett Packard hardware product is warranted against defects in material and workmanship for a period of three years from date of delivery HP software and firmware products which are designated by HP for use with a hardware product and when properly installed on that hardware product are warranted not to fail to execute their programming instructions due to defects in material and workmanship for a period of 90 days from date of delivery During the warranty period Hewlett Packard Company will at its option either repair or r
43. Output Storage amp Recall The power supply has 10 internal registers each of which can store the voltage and current settings of all the outputs By storing voltage and current settings for all outputs and recalling them later you can have significant savings in programming time See Supplemental Characteristics in Table 1 1 72 Remote Operation At power on each of the registers contain 0 volts and the minimum current limit To store voltage and current settings you must specify the register 1 to 10 For example to store the present settings of current and voltage of all your supply s outputs in register 2 send the following command STO 2 This command will take the programmed voltage and current settings of all output channels and store them in register 2 You can set the power supply outputs to these stored voltage and current settings by sending the recall command RCL 2 When a register is recalled the outputs will be set sequentially output 1 output 2 etc If you attempt to recall registers which were not previously stored then the supply will return the power on values for that register 0 volts and minimum current limit If you recalled registers outside the 1 to 10 range you will get a number range error The Clear Command This command will return the power supply to its power on state and all parameters are returned to their initial power on values except for the following 1 The store recall registers are not c
44. Outputs ooooonocccnonccnonccconaninnnnconnncnanccnnne 87 Calibration TICO UCA iaa 89 Test Equipment and Setup Required ooooccnnnnn eeseeesccssceceseecssceeesseecescecsscecsseecesaeeesaeecsaeesceeessaeeesseeesaeers 89 General Calibration Procedure sorer tat ea e ea a aeaa aea e a ae aasa ena 91 Calibration Proposal a a BSR r e a a a aoia 93 Programming With The Series 200 300 Computer NN 97 1VO Path Names ina inten E ee catia ies ee eines 97 Voltage and Current Programming 0 eeeessseessseecsseecsseecesaeeesaeecsaeecsaeecseecesseecsaeecsaeecsseesssaesesseessaaees 97 Voltage and Current Programming With Variables cescceeesecsseecsseeceseecesseecsaeecsaeecseeseseaeesseessaeees 98 Voltage anid Current Readback ranen eip sce ie geta veces cong Sed eneee eaa eaea ceag sted ae aa ae de aese oe as 98 Programming Power Supply Registers e sessseeeseesressrsssrseseseressrtseressttstrestitstirsretstesstesstesererereseresereserete 99 Present SUAUUS erotica R OEE EEN EEEE 99 Service Request and Serial Poll oooconnocinnoconicannoononononnoncnnonononancnnrno none i re a a 99 A A AS 101 Stored Operating Static aia 102 Programming Outputs Connected In Parallel oo onnnnccnonocionccnonaccncancnonnconnccnoncnconononnnncnonncnnccroncncnnnos 102 CE Operations titan ORO DL a ee a rin 103 GN iO peral tt o OA 103 Programming Outputs Connected In SerlesS ooooccnnonccnonccnonncnonnnnonononnnccnonncnonccnonnnnonnnonnnn
45. PROVIDED HEREIN ARE THE CUSTOMER S SOLE AND EXCLUSIVE REMEDIES HP SHALL NOT BE LIABLE FOR ANY DIRECT INDIRECT SPECIAL INCIDENTAL OR CONSEQUENTIAL DAMAGES WHETHER BASED ON CONTRACT TORT OR ANY OTHER LEGAL THEORY ASSISTANCE The above statements apply only to the standard product warranty Warranty options extended support contracts product maintenance agreements and customer assistance agreements are also available Contact your nearest Hewlett Packard Sales and Service office for further information on HP s full line of Support Programs SAFETY SUMMARY The following general safety precautions must be observed during all phases of operation service and repair of this instrument Failure to comply with these precautions or with specific warnings elsewhere in this manual violates safety standards of design manufacture and intended use of the instrument Hewlett Packard Company assumes no liability for the customer s failure to comply with these requirements BEFORE APPLYING POWER Verify that the product is set to match the available line voltage and the correct fuse is installed GROUND THE INSTRUMENT This product is a Safety Class 1 instrument provided with a protective earth terminal To minimize shock hazard the instrument chassis and cabinet must be connected to an electrical ground The instrument must be connected to the ac power supply mains through a three conductor power cable with the third wire firmly connected t
46. Refer to the Troubleshooting Section in the Service Manual Error codes 11 through 14 refer to a specific output where an output error has occurred Service is required Refer to the Output Board Troubleshooting section in the Service Manual Same as in error 11 Same as in error 11 Same as in error 11 The supply s model number cannot be found The HP IB Interface board may be defective or the supply may require reprogramming Refer to the Troubleshooting section of the Service Manual An error has occurred during calibration This may be the result of out of range numbers sent If recalibration See Appendix A does not fix this there may be a hardware failure Refer to the Troubleshooting Section in the Service Manual Table D 2 ERROR Responses continued Error Code Message ERR query ERR key UNCALIBRATED CAL LOCKED SKIP SLF TST Response Code TEST query Manual Explanation Unexplained EEPROM error possibly as the result of incorrect calibration procedure Recalibrate as described in Appendix A If the problem persists a hardware failure exists Refer to the Troubleshooting Section in the Service Manual Calibration was attempted with the calibration jumper on the HP IB board in the lockout position See Chapter 4 in the Service Manual Reposition the jumper and re calibrate if this is desired The self test jumper on the HP IB board is in the Skip Self Test Position See Chapter 4 in the Se
47. Refer to the Safety Summary page at the beginning of this manual for a summary of general safety information Safety information for specific procedures is located at appropriate places in this manual Instrument and Manual Identification Hewlett Packard power supplies are identified by a two part serial number i e 2601 A 00101 The first part of the serial number the prefix is a number letter combination that denotes either the date of manufacture or the date of a significant design change It also indicates the country of origin Starting at 1960 26 1986 01 the first week of the year A U S A The second part of the serial number is a different sequential number assigned to each instrument starting with 00101 If the serial number prefix on your power supply differs from that shown on the title page of this manual a yellow Manual Changes sheet that is supplied with this manual explains the difference between your instrument and the instrument described by this manual The change sheet can also contain information for correcting errors in the manual Options Options 100 120 220 and 240 simply determine which line voltage is selected at the factory For information about changing the line voltage setting see Line Voltage Conversion page 28 Option 750 consists of a fault indicator FLT and remote inhibit INH circuit and relay control which provide additional shutdown protection should either the HP IB and or controller fail
48. SP command during remote operation see page 78 A change between the local and remote modes will not result in a change in the power supply s outputs Local Control Of Output Functions The Output Function keys see Figure 6 1 allow you to control the selected output Figure 6 1 shows the annunciator arrow over OUTPUT 2 indicating that output channel 2 is selected Pressing the OUTPUT SELECT key selects the output channels in forward or reverse gt sequence Note that Figure 6 1 illustrates the front panel for the HP 6624A supply which has four output annunciators The HP 6627A front panel also has four annunciators The front panels for HP Models 6621A 6622A and 6623A are identical to Figure 6 1 except they have fewer output annunciators General The power supply will accept programming values directly in volts and amps The programmable voltage current and overvoltage ranges for the outputs of each model are given in Table 5 4 The power supply will round off the values received to the nearest multiple of the resolution for that particular output If you send a value out of the valid range it will not be executed and the ERR annunciator will come on You can get a readout of the error on the display by pressing the ERR key For an out of range error the error message NUMBER RANGE will be displayed When you press the VSET ISET OVSET DLY or UNMASK key the output selected and the present setting for that function will be disp
49. This Option is described in a separate document entitled Appendix E Option 750 Operating Instructions for the Multiple Output Linear System DC Power Supply HP Models 6621A 6622A 6623A 6624A and 6627A HP P N 5957 6372 100 Input power 100 Vac 47 66 Hz 120 Input power 120 Vac 47 66 Hz 220 Input power 220 Vac 47 66 Hz 240 Input power 240 Vac 47 66 Hz 700 Computer Interface Intermediate Language CIIL 750 Fault FLT Remote Inhibit INH and Relay Control 908 One rack mount kit 5062 3977 909 One rack mount kit with handles 5062 3983 910 One service manual with extra operating manual General Information 11 Accessories 10833A HP IB cable 1 m 3 3 ft 10833B HP IB cable 2 m 6 6 ft 10833C HP IB cable 4 m 13 2 ft 10833D HP IB cable 0 5 m 1 6 ft 10834A HP IB connector extender Slide mount kit 1494 0059 Description The HP 6621A 6624A and 6627A Multiple Output Linear Power Supplies feature a combination of programming capabilities and linear power supply performance that make systems applications The five models in this family offer a total of up to 200 watts of output power with voltages up to 50 volts and currents up to 10 amps The output combinations that correspond to each model are shown in Table 1 1 Each isolated output can supply power in two ranges as shown in Figure 1 1 This flexibility allows you to use the same output to power loads with different voltage and current requirem
50. ack the status of the supply over the HP IB The following protection features are implemented OVERVOLTAGE shorts the output by firing an SCR crowbar and sets zero volts and minimum current on an output if any of the following conditions are present 1 The output voltage exceeds the programmed overvoltage trip point or 2 The voltage from the V output terminal to the S terminal or from the S terminal to the V output terminal exceeds 1 5 V applies to remote sensing only or 3 A trip signal is received on the output s OV terminals or 4 The output s fixed overvoltage circuit is activated The OV trip point can be programmed up to 23 V on a low voltage output and up to 55 V on a high voltage output When an overvoltage occurs the word OVERVOLTAGE appears in the front panel display and the OV status bit is set for that output Chapter 5 explains how to program the overvoltage trip level 44 Output Connections and Operating Information do 40W LOW VOLTAGE OUTPUT 40W HIGH VOLTAGE OUTPUT l t 1 i i 1 8OW LOW VOLTAGE OUTPUT 8OW HIGH VOLTAGE OUTPUT V QUADRANT 2 QUADRANT 1 I VOLTAGE OUTPUT LOW QUADRANT 3 QUADRANT 4 RANGES RANGE V LOW HIGH QUADRANT 1 CV OR CC OPERATION CURRENT OUTPUT QUADRANT 2 CURRENT SINK OPERATION CV OR CC QUADRANT 7 RANGES QUADRANT 4 REVERSE DIODE CHARACTERISTIC Figure 4 2 Typical Output Range Characteristics Output Connecti
51. ad resistance is an important factor relating to the CV stability of the supply with remote sensing of capacitive loads If high capacitance loads are expected you should not use wire gauges heavier than 12 to 14 AWG for long runs of load lead See Figure 1 4 for more information about stability with output capacitors 48 Output Connections and Operating Information Multiple Loads If you are using the as shipped terminal block strapping pattern local sensing and are connecting multiple loads to one output connect each load to the output terminals using separate connecting wires see Figure 4 4 This minimizes mutual coupling effects and takes full advantage of the power supply s low output impedance Each pair of wires should be as short as possible and twisted or bundled to reduce lead inductance and noise pickup If load considerations require the use of distribution terminals that are located remotely from the supply connect the power supply output terminals to the remote distribution terminals by a pair of twisted or bundled wires Connect each load to the distribution terminals separately Remote voltage sensing is recommended under these circumstances Sense either at the remote distribution terminals or if one load is more sensitive than the others directly at the critical load TIE WRAPS LOAD LEADS PARALLEL AND CLOSE TOGETHER 4 Figure 4 4 Optimum Hookup for Multiple Loads Local Sensing NOTE When a load is
52. adden Satoh tients 46 Wite Size Selections eeen eee ea 47 Multiple Loads Aia 49 Table Of Contents continued Positive and Negative Voltages ceseccsssecsscecsseecsseeceseceesseecsscecsseecsseecesaeeesseeesneecsseeseseeeesaeeesaeers 49 Remote V olta se Sensing a ii eet eee eae ems eaten 49 Remote Sense Connections ico lada idad 50 Output Noise Considerations ccceeccessccssseecsncecsseecsscececcecesseecsaeecseecsseecesaeeesseecsseesseeseneeeesaeeesaeers 51 Programming Response Time with an Output CapacitOT coocccooccnnonncnonncnnn coneecsneecsseeeeseeeesaeecsaeeesneeesea 51 Open Sense E o E A A a lin 51 Overvolt ge Trigger CONNECHONS accurate ranita dla ide 52 External EOS Ct detailed tas 52 Power Supply Protection Considerations oooonooccnonccnonncn n coscecesceeesseecsseecsacecsceeceseecsaeecseesseesesaeeesaeeesneees 54 Battery Char sini Sennaa AAA 54 Capacitive Load Limitation ieaie did dl 54 AUR eene aneneen ee Ea poate css bang Ale waite dss cten Eee aati vet bead ian ieee casita nots eat eee teenth DRAEN 54 CV Operator ia 55 CE Operators dd dt al Lt be 56 Remote Sens ip io 56 Specifications for Parallel Operati0N ooocnonccnonocnnonccoonncoonnnonnnnononccnonccnonnnonnnnononnonnncnonnncnnnnonnnncnonccnnne 56 Series Operation unicas 57 CY Operations oir octet sd E ea teste a O ad od ae av oid abi a oak E anaes 57 CE Operations acistccvaddisinty pun it is ds hee ded nee eet detest 58 AS Oss Jonette
53. and Operating Information 51 Overvoltage Trigger Connections Each output of your power supply has two OV terminals on its rear panel terminal block These terminals are labeled OV and OV By connecting the OV terminals all in parallel as shown in Figure 4 7 an overvoltage shutdown on any one output will also trigger the overvoltage on the remaining outputs Any number of OV terminals up to eight sets can be strapped together Observe polarity when connecting the OV terminals in parallel EXTERNAL OV TRIGGER SRA Figure 4 7 Overvoltage Connections The overvoltage trip point for each output can be set either from the front panel or by remote programming You can also externally fire the overvoltage circuit of one or more outputs by applying a 5 volt pulse of at least 50 US to any pair of OV terminals see Figure 4 8 As long as all OV terminals are wired together the outputs will be crowbarred simultaneously External Trigger Circuit Figure 4 8 illustrates a recommended external circuit that can be used to provide an OV trip signal to the OV terminals This circuit configuration provides good noise immunity and protects against the voltage pulse that is returned from the OV terminals every time that the overvoltage circuit fires It can be operated from a wide range of bias voltages provided the input limiting resistors are chosen as tabulated in the figure
54. and identical outputs can be operated in series or parallel combinations for increased output voltage or current capability As shipped from the factory the power supply is jumpered for local sensing Your power supply can be calibrated without having to remove the cover or even having to remove it from your system cabinet This feature allows you to calibrate the supply at its normal operating temperature The recommended calibration interval is one year Refer to Appendix A of this manual for complete calibration details A calibration security jumper is available inside the unit Access is described in the service manual Basic Operation Figure 1 2 is a block diagram that illustrates the major assemblies contained within the power supply As shown in the figure each supply includes a power transformer two or more output boards an HP IB board and front panel display and control keys HIGH Output Low Range Values High Range Values oad 80 W Low Voltage 7V010A 20V04A f 2 BOTH LOW RANGES RANGE 2 9 a HIGH CURRENT OUTPUT Figure 1 1 Output Operating Ranges for HP Models 6621A 6624A and 6627A The appropriate ac input voltage is applied to each output board where it is converted to a raw dc voltage which is subsequently linearly regulated to become the de output voltage The magnitude of the output and the mode of operation are determined by the load and the data received from the HP IB computer or from the fro
55. and the ERR bit in the serial poll register will be set When in local mode the supply will display the error name in response to pressing the ERR key on the front panel Over the HP IB only the error code will be returned After a query the error bit is cleared A description of these codes is given in Table 5 8 To find out what the error is send the following query and address the supply to talk ERR The supply will respond with an error code number see Table 5 8 ID Query If you want to know the model number of the power supply you are working with you can send the ID query over the HP IB To do this send the following over the HP IB and address the supply to talk ID The supply will respond with its model number Test Query You can get the power supply to perform a limited self test at any time during its operation by sending the TEST query over the HP IB This test does not affect the analog control circuits of the supply and it can be performed while the outputs are connected to external circuits For tests of the analog control circuits refer to Chapter 3 Responses to the test query are described in Table 5 9 This test cannot be done from the front panel To instruct the power supply to carry out a self test send the following query and address the supply to talk TEST Calibration Mode Query To be able to calibrate your power supply the calibration mode CMODE must be turned on See Appendix A for a detailed description o
56. ariable in the computer The following program queries the power supply for the voltage and current settings of output and prints the results on the screen 98 Programming with a Series 200 300 Computer 10 ASSIGN Ps TO 705 20 OUTPUT Ps VSET 1 30 ENTER Ps Vsl 40 OUTPUT Ps ISET 1 50 ENTER Ps Isl 60 PRINT VOLTAGE SETTING OF OUTPUT 1 Vsl 70 PRINT CURRENT LIMIT SETTING OF OUTPUT 1 sIs1 80 END Line 10 Assigns the I O pathname to the power supply Line 20 30 Queries the supply for output 1 s voltage setting You cannot string multiple queries together in a single device command because the power supply can only return the most recently queried data Line 40 50 Queries the supply for output 1 s current limit Line 60 70 Prints the results of the queries on the screen Programming Power Supply Registers Present Status The power supply makes available several forms of status information Chapter 5 discusses the different registers and their functions The present status register contains continuously updated information The following example shows how to query bit position 0 of output 1 s status register to see if output 1 is in CV mode In this example the program references the function as a variable in a conditional execution statement Note that instead of printing a message line 30 could be used to branch to another part of the program in the event that the supply is in CV mode 10 ASSIGN Ps TO 705 20 COM
57. ation program is written with the assumption that your power supply is at address 705 and the voltmeter is at address 722 The program will ask you which output is to be calibrated and will prompt you to make the voltage and current calibration connections shown in Figure A 1 10 CALIBRATION EXAMPLE 20 30 ASSIGN Ps TO 705 40 ASSIGN Vm TO 722 50 COM Instr Ps Vm 60 Shunt_resistor 1 70 80 OUTPUT Ps CLR 90 OUTPUT Vm H T4 100 TRIGGER 722 110 ENTER Vm Temp CLEAR VOLTMETER OUTPUT BUFFER 120 OUTPUT Ps CMODE 1 130 140 Start_loop LOOP TO HERE FOR ADDITIONAL OUTPUTS 150 160 INPUT ENTER OUTPUT CHANNEL TO BE CALIBRATED 1 2 3 or 4 Chan 170 DISP SET UP OUTPUT Chan FOR VOLTAGE CALIBRATION amp PRESS CONTINUE 180 PAUSE 190 200 OUTPUT Ps VHI Chan 210 Vhi FNDvm 220 230 OUTPUT Ps VLO Chan 240 Vlo FNDvm 250 260 OUTPUT Ps VDATA Chan Vlo Vhi 270 280 IF FNPs _ err lt gt 0 THEN Finish 290 300 OUTPUT Ps OVCAL Chan 310 REPEAT 320 DISP WAITING FOR OVERVOLTAGE CALIBRATION 330 UNTIL BIT SPOLL Ps 4 340 350 IF FNPs _ err lt gt 0 THEN Finish 360 370 DISP SET UP OUTPUT Chan FOR CURRENT CALIBRATION amp PRESS CONTINUE 380 PAUSE 390 400 OUTPUT Ps IHI Chan 410 Thi FNDvm Shunt _ resistor 420 430 OUTPUT Ps ILO Chan 440 Ilo FNDvm Shunt _ resistor Calibration Procedures 93 450 460 OUTPUT Ps IDATA Chan Tlo thi 4
58. ccumulated Status Register Each output channel of the power supply also maintains a cumulative status in its accumulated status astatus register This register records every status condition the power supply output entered since it was last queried When queried it returns a decimal number which is decoded as shown below The astatus register is reset to the present value of the status register after it is queried The bits are assigned as in Table 5 5 Here is an example to help you decode the decimal number from 0 to 255 returned when the astatus register is queried If the output channel was in overvoltage since the last reading of the astatus register and that channel is presently operating in constant voltage mode the reading you will get when you query the register will be 9 To decode this we use table 5 5 9 8 1 OV CV For example to query the astatus register of output 2 send the following query and address the supply to talk ASTS 2 74 Remote Operation The Mask and Fault Register The fault register works in conjunction with the mask register These are two eight bit registers which report any fault condition on a particular output channel The mask register is used to set up the conditions that generate a fault which is latched into the fault register The user can then read the fault register to determine the fault When a bit in the fault register is set the power supply can generate a service request for that output provi
59. ceptacle so that after the door is closed the red notch shows through the window next to the voltage level you require CAUTION It is possible to insert the voltage selector card so that a red notch is not visible through any of the four windows Do NOT operate the power supply while the selector card is in this position Also on page 27 replace figure 2 3 with the following figure DOOR OPEN LINE VOLTAGE INDICATOR SHOWN IN 12 V POSITION 174 X 1 1 4 FUSE OR SMM X 2 MM FUSE VOLTAGE SELECTOR CARD Figure 2 3 Line Module Detail Manual Backdating 113 ADDENDUM I Generally Applicable Annotations Consistent with good engineering practice leads attached to customer accessible signal monitoring ports such as the 10 pin Control Connector the 7 pin Analog Connector the 7 pin Digital Port Trigger Connector screw terminal Barrier Blocks etc should be twisted and shielded to maintain the instrument s specified performance ll CE 92 Product Specific Annotations 114 When tested for radiated susceptibility as called for in EN 50082 1 per the EC EMC directive the following changes in the Supplementary Characteristics of the 6621A and 6623A have been noted 6621A When subjected to radiated field strengths of 3 volts meter in the vicinity of 90 MHz the full scale programming accuracy of channel 2 increases from 31 millivolts at 20 volts output to 700 millivolts The accuracy reverts to the published value of 31 millivol
60. circuits of the power supply and the controller The ADDR annunciator indicates when the power supply is addressed to listen or talk The talker function includes the Serial Poll see page 62 Service Request This is a message which can be initiated by the power supply to request service from the controller When the supply is requesting service it asserts the service request SRQ line on the HP IB to interrupt the controller Remote Operation 61 providing the controller is configured to service interrupts A service request can be generated whenever there is a fault on one of the outputs up to 4 outputs a programming error has occurred or at power on providing certain commands are sent Service request commands are discussed in detail on page 76 The SRQ annunciator on the front panel display is turned on when the power supply is requesting service from the computer and remains on until the controller conducts a serial poll A serial poll removes the service request and turns off the SRQ annunciator regardless of whether the condition that caused the service request continues to exist The service request is also removed when you send the CLR command see page 73 Remote Local The power supply can receive programming information either from the HP IB remote or from the front panel local When the power supply is in remote the state of the supply cannot be changed by using the front panel keys although the LCL key will remain enabl
61. cluded with the rack mounting kits Installation 25 OUTPUT 2 i 497 8mm I z alalaaajaja 19 6 OUTPUT 2 AND 3 CUTE 3 0V 0V S V V 5 518 2mm 28 4 OUTPUT 1 AND 4 S V V S 0V 0V 132 6mm leeke AL ERMINAL STRIP DETAIL SIDE Note Outputs 3 and 4 are not used in all models __ Figure 2 1 Outline Diagram Input Power Requirements You can operate this power supply from a nominal 100 V 120 V 220 V or 240 V single phase power source at 47 to 66 Hz The input voltage range maximum input current high line inrush current PK and the fuse required for each of the nominal inputs are listed in Table 2 1 You can check the line voltage setting of your supply by examining the door on the line module This is located on the rear panel of your supply as shown in Figure 2 2 If necessary you can convert the supply from one line voltage setting to another by following the instructions under Line Voltage Conversion page 28 Table 2 1 Input Power Nominal Voltage Line Voltage Maximum Input High Line Inrush Current Fuse Range Current rms PK 100 V 6 3 A 85 A 8A 120 V Nominal 57A 85A 8A 220 V 13 6 3 0 A SOA 4A 240 V 3 0 A SOA 4A Line Fuse The ac line fuse is located behind the door on the line module see Figure 2 3 To access the fuse remove the power cord and push against the tab on the line module in the direction of the ac input socket The current rating of the fuse is based o
62. d you to the supply s front panel controls and indicators to help you turn on the supply and perform the checkout procedures that were given in that chapter The following paragraphs describe how to use all of the front panel controls and indicators Most of the remote operations described in Chapter 5 can also be performed locally from the supply s front panel Local Mode In order to use the front panel keys to control the supply the local mode must be in effect The local mode is in effect immediately after power is applied Table 5 3 lists the initial settings for all of the power supply s functions when power is initially applied When the local mode is in effect RMT annunciator off the Output Function System Function and Numeric Entry keys on the front panel see Figure 6 1 can be used to operate the power supply In the remote mode front panel RMT annunciator on the front panel keys will have no effect on any of the supply s outputs and only the computer can control the supply You can however still use the front panel display to view the output voltage and current readings or the present settings for the selected output channel while the supply is in the remote mode You can return the supply to the local mode from the remote mode by pressing the LCL key provided that the local lockout command has not been received from the HP IB controller Pressing the LCL key will also turn the supply s display back on if it was turned off with a D
63. desired voltage appears on the top left side of the board Push the board all the way back into its slot The desired line voltage must be visible when the board is installed 5 Install the correct fuse in the door of the line module if your line voltage change also requires a change in the rating of the fuse see Table 2 2 28 Installation FIRE HAZARD Make sure the replacement fuse is one of the same type size and rating amps that is consistent with the voltage level you are operating at Do not use a substitute fuse use a fuse with the same HP Part number listed in Table 2 2 6 Close the door of the line module and insert the power cord in the ac input socket Your power supply is now configured to operate at the voltage you selected HP IB Interface Connector The HP IB connector on the rear panel connects your power supply to your computer and other HP IB devices see Figure 2 2 Chapter 1 page 12 lists the cables and cable accessories that are available from Hewlett Packard An HP IB system can be connected together in any configuration star linear or both as long as the following rules are observed 1 The total number of devices including the computer is no more than 15 2 The total length of all the cables used is no more than two meters times the number of devices connected together up to a maximum of 20 meters NOTE IEEE Std 488 1978 states that you should exercise caution if your individual cable lengths exceed
64. ding on the load one output may operate in the unregulated mode Output Connections and Operating Information 55 CC Operation For CC operation set the output voltages as outlined in CV operation page 55 or alternatively program the voltage settings of both outputs to the same voltage limit point Then program the current of each output so that the sum of both currents equals the total desired operating current The simplest way to accomplish this is to program each output to one half of the total desired operating current Both outputs will operate in the CC mode Remote Sensing If it is necessary to remote voltage sense at the load parallel the sense leads of output 1 with the sense leads of output 2 and connect to the load as shown in Figure 4 12 The outputs can be programmed as previously described Additional information on programming outputs connected in parallel is given in Appendix B OUTPUT 2 SENSE JUMPERS REMOVED OUTPUT 1 SENSE JUMPERS REMOVED Figure 4 12 Parallel Connections with Remote Sensing Specifications for Parallel Operation Specifications for outputs operating in parallel can be obtained from the specifications for single outputs Most specifications are expressed as a constant or as a percentage or ppm plus a constant For parallel operation the percentage portion remains unchanged while constant portions or any constants are changed as ind
65. ding the service request command on fault SRQ 1 or SRQ 3 was previously sent See page 76 for a discussion on service request To understand how these two registers work we must include the status register in this discussion Recall that the status register takes its input from the power supply and the user cannot change its contents The mask register takes its inputs from the user and the power supply cannot change its contents The fault register takes its inputs from both the mask and the status registers You can find out the setting of the mask register of output 2 by sending the following query and addressing the supply to talk UNMASK 2 The response will be a numeric code between 0 and 255 which can be decoded by consulting Table 5 5 You can set the conditions to generate a fault by setting unmasking one or more bits in the mask register The conditions will remain unmasked until you change them To unmask conditions in output 2 for example send the following command UNMASK 2 XXX where XXX specifies the numeric code 0 to 255 for the unmasked conditions see Table 5 5 If during operation the output experiences any of the previously unmasked conditions it will set the corresponding bit s in its fault register Remember that the bits in the fault register can be set when there is a change in either the status register or the mask register Each output has its status mask and fault registers arranged as shown in Figure 5 3 and
66. e The output that is operating in CV mode will be controlling the voltage regulation of both outputs In the example that follows outputs 1 and 2 both 40 W or 80 W Low V channels will be operating in parallel with output 1 in CV mode and output 2 in CC mode at output voltages above 2 5 V Each is programmed to one half of the desired current limit point Above 2 5 V the voltage for output 2 is always programmed higher than that of output to ensure that output 2 operates in the CC mode Note that any current from output 2 that is not required by the load flows into the downprogrammer of output 1 and is reflected in the current readback of output 1 The total current supplied to the load can be read back by adding the results of reading back the currents of outputs 1 and 2 At 2 5 V and below the outputs are set to the same voltage and the operating modes depend upon the load 10 ASSIGN Ps to 705 20 INPUT ENTER OPERATING VOLTAGE V1 30 INPUT ENTER TOTAL CURRENT LIMIT Ilim 40 C Ilim 2 50 IF V1 gt 7 THEN V2 20 2 60 IF V1 lt 7 THEN V2 7 07 70 IF VI lt 2 5 THEN V2 V1 80 OUTPUT Ps CLR ISET1 C VSET1 V1 90 OUTPUT Ps ISET2 C VSET2 V2 100 WAIT 1 110 OUTPUT Ps VOUT 1 120 ENTER Ps Vout 130 OUTPUT Ps IOUT 1 140 ENTER Ps Ioutl 150 OUTPUT Ps IOUT 2 160 ENTER EPs lout2 170 PRINT OUTPUT VOLTAGE IS Vout 180 PRINT TOTAL OUTPUT CURRENT IS loutl Iout2 190 END Programming with a Series 200 300
67. e to be displayed at the front panel The error register is cleared after being read FAULT lt ch gt Queries the fault register of the specified output channel see Mask and Fault Register page 74 A bit is set in the fault register when the corresponding bit in both the status and the mask registers The response is an integer O to 255 The fault register is cleared after being read Queries the identification model number of the supply Response can be HP 6621A HP 6622A HP 6623A HP 6624A or HP 6627A as applicable see ID Query page 79 IDATA lt ch gt lt Ilo gt lt Ihi gt Sends data to calibrate the current setting and readback circuits of the specified output channel Ilo and Ihi are measured values which the supply uses to calculate correction constants see Appendix A THI lt ch gt Causes the current of the specified output channel to go to the high calibration point see Appendix A ILO lt ch gt Causes the current of the specified output channel to go to the low calibration point see Appendix A IOUT lt ch gt Queries the measured output current of the specified output channel see page 69 The response is a real number The front panel display can be used to monitor the measured output current and voltage of the selected output channel ISET lt ch gt lt current gt Sets the current of the specified output channel see page 69 ISET lt ch gt Queries the present current setti
68. e 4 10 illustrates the recommended connections and protection circuit for a battery charging application The diode will prevent damage to your supply that can result from excessive battery current flowing into the supply s output in the event of an overvoltage shutdown BATTERY NOTE IF REMOTE SENSING CONNECT SENSE LEAD TO ANODE SIDE OF DIODE S r 1 Figure 4 10 Recommended Protection Circuit for Battery Charging Capacitive Load Limitation The programmable overvoltage protection circuit can be used to downprogram capacitive loads although it is primarily intended for use as a protection feature page 44 Repetitive over 100 cycles tripping of the overvoltage circuit with output capacitors greater than 5000uF on high voltage units and 20 000UF on low voltage units may result in eventual damage to the supply Parallel Operation CAUTION Connect in parallel only outputs that have equivalent voltage and current ratings Connecting outputs in parallel provides a greater current capability than can be obtained from a single output Because each output contains an active downprogrammer that is capable of sinking current from only ONE identical output you can parallel no more than two outputs These outputs must have equivalent voltage and current capability For example you can connect the 40 W low voltage outputs together because they have the same voltage and current ratings but you cannot c
69. e OVP Ranges 0 23 V 0 55 V 0 23 V 0 55 V Load Cross Regulation Voltage 1mV 2 5 mV 1mV 2 5 mV Current 1 mA 0 5 mA 2 mA 1 mA Output Response Characteristics See Figure 1 3 Max Output 2 ms 6 ms 2 ms 6 ms Programming Response Time Settling Band 20 mV 50 mV 20 mV 50 mV Max Time Constant 250 uS 750 uS 250 uS 750 uS DC Floating Voltage No output terminal may be more than 240 Vdc from any other terminal or from chassis ground Also no overvoltage terminal may be more than 240 Vdc from any other terminal or chassis ground Remote Sense Capability See wire size selection page 47 and remote voltage sensing page 48 Outputs can maintain specifications with up to 1 volt drop per load lead except that the maximum voltage at the output terminals must not exceed the rated output voltage 1 volt see Figure 4 6 If the steady state voltage drop exceeds approximately 1 5 V on either load lead when remote sensing a circuit will trip the OVP 18 General Information Table 1 3 Supplemental Characteristics continued Outputs 40 W Low 40 W High 80 W Low 80 W High Voltage Voltage Voltage Voltage Programming Resolution Voltage Current OVP Readback Resolution Voltage 6 mV 15 mV 6 mV or Current 2mA 0 8 mA 4mA Fixed Overvoltage Protection Measure at output terminals V and V Minimum 22 5 V 56 V 22 5 V Nominal 24 V 60 V 24 V Maximum 26 V 64 V 26 V AC Input Power and Current Maximum Power 550 W 100 V Option 120 V Op
70. e displayed response is the power supply s HP IB address When sending a remote command you append this address to the computer s HP IB interface select code normally 7 For example if the select code is 7 and the power supply s HP IB address is 5 the combination is 705 Changing the HP IB Address NOTE All examples in this discussion assume an HP IB address of 5 It is recommended that you retain this address to simplify programming Every device on the HP IB must have an address The supply s address is factory set to decimal 5 Any address from 0 through 30 is a valid address If you need to change the HP 662xA Supply s address press You can now enter a new address For example press You have now changed the address from 5 to 14 If you want to change the address back to 5 repeat the above procedure but use 5 instead of 14 in the last step Note that the address is stored in the power supply s non volatile memory and therefore will be retained through interruption of the ac line power Sending a Remote Command To send the power supply a remote command combine your computer s output statement with the HP IB interface select code the HP IB device address and finally the power supply command For example to set the output voltage of output channel to 2 volts send Getting Started 39 HP 662xA Command Header Output Voltage Value HP IB Interface Select Cod yee OUTPUT 705 VSET 1 2 HP BASIC Statement f Output C
71. e fundamentals of operating the supply remotely from a computer You will learn how to send a command to the supply from the computer and how to get data back to the computer from the power supply A few of the most often used power supply commands will be described to help you get started and become familiar with the basics of programming your supply After completing this chapter you can proceed to Chapter 4 to find out how to make load connections to your supply s outputs and then to Chapter 5 Remote Control and or Chapter 6 Local Control to learn all the details about operating your supply Front Panel Controls and Indicators The power supply s controls and indicators are shown in Figure 3 1 and are described in Table 3 1 Note that the front panel controls are identical for HP Models 6621A 6624A and 6627A except for the number of OUTPUT annunciators number 3 in Figure 3 1 The HP Model 6624A shown in Figure 3 1 has four outputs as does the HP 6627A HP Models 6621A and 6622A each have two outputs and HP Model 6623A has three outputs Table 3 1 in addition to providing a brief description of each control and indicator lists the paragraphs in which the use of each control and indicator is described Because most of the functions performed by the front panel controls can also be performed remotely by power supply commands the corresponding paragraphs in Chapter 5 Remote Operation are listed in Table 3 1 where applicable Turning
72. ecause of inductance effects The sense leads carry only a few milliamperes of current and therefore can be lighter gauge than the load leads However note that any voltage drop in the sense leads can degrade the voltage regulation of the supply Try to keep the sense lead resistance less than about 0 5Q per lead this requires 20 AWG or heavier for a 50 foot length You can use the following formulas to calculate the CV load regulation error when using remote sensing 50 Output Connections and Operating Information OUTPUT TYPE FORMULA 40 W amp 80 W Vset Vdrop LV Output CV Reg Error mV Rs as A Vset Vdrop HV Output CV Reg Error mV Rs 105 33 CV Regulation Error Remotely sensed voltage will change by this number of millivolts Rs Resistance of each sense lead in 2 Vset Programmed voltage value in volts Vdrop Total drop in the load leads in volts In addition include 1 mV error per 200 mV drop in the V load lead independent of Rs value Output Noise Considerations Any noise picked up on the sense leads will appear at the supply s output and may adversely affect CV load regulation Twist the sense leads or use a ribbon cable to minimize the pickup of external noise In extremely noisy environments it may be necessary to shield the sense leads Ground the shield at the power supply end only do not use the shield as one of the sensing conductors The noise specifications in Table 1 1 apply at the power
73. ed Remote operation takes precedence over local operation hence if the supply is accepting commands remotely and you attempt to change it to local operation the supply will not allow any local settings and will remain in remote You can prevent the front panel from sending programming information by sending the local lockout command This command is sent only from the HP IB If you change from local to remote or vice versa there will be no change in the programmed settings Parallel Poll Parallel Poll allows the controller to receive at the same time one bit of data from each of up to eight instruments connected to the bus HP power supplies designate bit 6 the RQS bit of the serial poll register for this operation By checking the status of this bit the computer can quickly determine which instruments on the bus requested service Once an instrument is identified the computer can perform a serial poll to find out the exact cause of the request Parallel Poll does not reset this service request bit RQS in the power supply NOTE TEEE 488 does not define what data an instrument should put on a bus in response to parallel poll Many instruments such as Hewlett Packard power supplies indicate the state of their RQS bit but the operator should not assume that all instruments on the bus respond to parallel poll with their RQS bit Unless remotely configured the power supply will respond with a 1 on one of the HP IB data lines if it is requesting ser
74. ed output Setting Current The selected output s current is programmed locally using the ISET key For example program the current to 1 5 amps by pressing vser 1 5 enter The power supply will accept any programmed current between zero and the minimum programmable current and automatically set the output to the minimum programmable current without causing a programming error See Table 5 4 NOTE As described on page 70 each output channel has a dual output range The range is determined by the last value of voltage VSET or current ISET programmed 84 Local Operation Enabling Disabling an Output The selected output channel can be turned on and off from the front panel The OUTPUT ON OFF key toggles the selected output on and off When an output is turned off the message DISABLED will be displayed The OUTPUT ON OFF key will not affect any other programmed functions nor will it reset an overvoltage or overcurrent condition An output disabled by the OUTPUT ON OFF key will behave as if it were programmed to zero volts and minimum current Setting Overvoltage Protection Programmable overvoltage protection OVP guards your load against overvoltage by crowbarring and downprogramming the power supply output if the programmed overvoltage setting is exceeded A fixed OVP circuit with a trip level about 20 percent above the maximum programmable voltage acts as a backup to the programmable OVP When overvoltage protection i
75. el is in constant current CC mode of operation then the actual current is the programmed current but if the output is in the CV mode the programmed current is the current limit of that output To readback the programmed current for output 1 send the query and addressing the supply to talk ISET 1 You can also instruct the supply to measure the actual output current at output channel 1 by sending the following query and address the supply to talk IOUT 1 The results are placed on the HP IB and read into the controller Remote Operation 69 Table 5 4 Programmable Output Ranges for the HP 662IA 6624A and 6627A Supplies Output Operating Output Voltage Output Overvoltage Channel Range Avg Current Avg Range Avg Resolution Resolution Resolution 6621A 1 amp 2 0 to 7 07 V 0 13 to 10 30 A 0 to 23 V 80 W Low V 0 to 20 2 V 0 13 to4 12 A 0 10 V 0 006 V 0 050 A 6622A 1 amp 2 0 to 20 2 V 0 07 to4 12 A 0to55 V 80 W High V 0 to 50 5 V 0 07 to 2 06 A 0 25 V 0 015 V 0 020 A 0 to 20 2 V 0 05 to 2 06 A 0 to 55 V 0 to 50 5 V 0 05 to 0 824 A 0 25 V 0 015 V 0 010 A 0 to 7 07 V 0 08 to 5 15 A 0 to23 V 0 to 20 2 V 0 08 to 2 06 A 0 10 V 0 006 V 0 025 A 0 to 20 2 V 0 05 to 2 06 A 0 to 55 V 0 to 50 5 V 0 05 to 0 824 A 0 25 V 0 015 V 0 010 A 6627A 1 4 0 to 20 2 V 0 05 to 2 06 A 0to55 V 40 W High V 0 to 50 5 V 0 05 to 0 824 A 0 25 V 0 015 V 0 010 A The maximum programmable voltage values for each
76. emote Operation NOTES ZA DU WN eR Output channels 3 and 4 are not used in all models See Table 5 4 Applies to 80 W Low V output Applies to 40 W High V and 80 W High V outputs X depends upon model A space is returned for a sign All responses are followed by a lt CR gt and lt LF gt EOI asserted with lt LF gt Spaces are allowed between the header and the question mark Remote Operation 67 Order of Execution When you send a set of instructions to the power supply they are executed in the order in which they are received The power supply completes the execution of the present command before executing another command To send more than one command within the power supply command string use a semicolon to separate the commands This maximizes the rate at which the power supply accepts commands Terminators Terminators mark the end of a command string As shown in Figure 5 2 the semicolon line feed lt LF gt and carriage return line feed lt CR gt lt LF gt are the characters that indicate the end of a message to the power supply When you are using the HP Series 200 computer with BASIC to send a command using the standard format see Figure 5 1 the computer automatically sends lt CR gt lt LF gt on the data bus following the command Initial Conditions Immediately after power on the power supply automatically undergoes a self test and sets all parameters to their ini
77. ent Programming With Variables You can use variables in a program to represent data values in the device commands This is useful in applications that require changing the voltage and current values to different predetermined settings The following program uses a variable in a FOR NEXT loop to ramp up output voltage in 0 1 volt steps from 0 to 5 volts 10 ASSIGN Ps TO 705 20 OUTPUT Ps CLR ISET1 1 30 FOR Voltage 0 TO 5 STEP 0 1 40 OUTPUT Ps VSET1 Voltage 50 WAIT 0 2 60 NEXT Voltage 70 END Line 10 Assigns the I O pathname to the power supply Line 20 Initializes the power supply to its power on state and sets the current limit Line 30 60 Increments the voltage in 0 1 V steps to 5 volts Line 40 Sets the voltage of output 1 to the value of the variable Voltage The comma inside the quotes is required because it separates numbers in the device command the output channel number from the voltage value in this case A space lt SP gt may also be used instead of the comma The semicolon outside the quotes is used because it suppresses the lt CR gt lt LF gt that the computer would normally send to the power supply if a comma were used as a separator after a string item Using a comma in this case would produce a syntax error in the power supply Line 50 Waits 0 2 seconds between steps Another way to use variables to represent data values in device commands is when using input statements to program the power supply The f
78. ents No separate command is required to program ranges the power supply automatically selects one of the operating ranges based on the last parameter voltage or current that is set Additionally each output contains an active downprogrammer which means that voltage downprogramming can be accomplished as quickly as upprogramming even without a load Table 1 1 Output Combinations Available HP 6621A 80 W Low Voltage 80WLowVoltage Jo HP 6622A 80W High Voltage 80WHigh Voltage o Z y O HP 6623A 40 W Low Voltage 80 W Low Voltage 40 W High Voltage HP 6624A 40 W Low Voltage 40 W Low Voltage 40 W High Voltage 40 W High Voltage HP 6627A 40 W High Voltage 40 W High Voltage 40 W High Voltage 40 W High Voltage The output voltage and current for any output can be monitored with the front panel display Output specific error messages are also displayed Front panel annunciators show the operating status of the instrument The front panel keypad lets you set and readback the voltage limit current limit and overvoltage trip level of any output With the keypad you can also enable or disable outputs mask and delay bits in the fault register enable overcurrent protection reset overvoltage and overcurrent protection and return to local operating mode Your multiple output power supply can be both a listener and a talker on the HP IB HP IB is Hewlett Packard s implementation of IEEE 488 The built in interface is tailored t
79. eplace products which prove to be defective HP does not warrant that the operation for the software firmware or hardware shall be uninterrupted or error free For warranty service with the exception of warranty options this product must be returned to a service facility designated by HP Customer shall prepay shipping charges by and shall pay all duty and taxes for products returned to HP for warranty service Except for products returned to Customer from another country HP shall pay for return of products to Customer Warranty services outside the country of initial purchase are included in HP s product price only if Customer pays HP international prices defined as destination local currency price or U S or Geneva Export price If HP is unable within a reasonable time to repair or replace any product to condition as warranted the Customer shall be entitled to a refund of the purchase price upon return of the product to HP LIMITATION OF WARRANTY The foregoing warranty shall not apply to defects resulting from improper or inadequate maintenance by the Customer Customer supplied software or interfacing unauthorized modification or misuse operation outside of the environmental specifications for the product or improper site preparation and maintenance NO OTHER WARRANTY IS EXPRESSED OR IMPLIED HP SPECIFICALLY DISCLAIMS THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE EXCLUSIVE REMEDIES THE REMEDIES
80. er accurate to 0 003 of reading 3 A precision 0 1 Q 0 05 10 amp shunt resistor 4 terminal Figure A 1 shows the setup required for calibrating both voltage and current Observe polarity when connecting the voltmeter Note that for voltage calibration the voltmeter leads are connected to the S and S terminals and NOT the V and V terminals Note that for both and current calibration the voltmeter leads are connected to the shunt resistor s sense terminals Calibration Procedures 89 90 Calibration Procedures l OUTPUT TERMINAL BLOCK COMPUTER VOLTAGE CALIBRATION OUTPUT TERMINAL BLOCK COMPUTER CURRENT CALIBRATION Figure A 1 Calibration Setup Table A 1 Calibration Commands Command Header Channel Data Syntax Range see Figure 5 2 Calibration Mode 0 1 off on C2 Set High Voltage VHI 1 2 3 4 C3 Set Low Voltage VLO 1 2 3 4 C3 Set High Current IHI 1 2 3 4 C3 Set Low Current ILO 1 2 3 4 C3 Calibrate Overvoltage OVCAL 1 2 3 4 C3 Voltage Data VDATA 1 2 3 4 see Table A 2 C5 Current Data IDATA 1 2 3 4 see Table A 2 C5 Channels 3 and 4 are not used in all models Table A 2 Voltage and Current Data Ranges Voltage Range in Volts Current Range in Amps Vio Vhi llo Ihi Output Min Max Min Max Min Max Min 40 W Low Voltage 0 0 1 18 5 20 5 0 0 15 4 5 40 W High Voltage 0 04 0 20 44 48 80 W Low Voltage 0 0 1 80 W High Voltage General Calibration Procedure CAUTION This procedure causes
81. er on or off The parameter must be either a 1 or a0 CMODE1 is used in the beginning of the calibration procedure to turn calibration mode on CMODE must be on to use any of the calibration statements CMODEO is used at the end of the procedure to store the correction constants and turn calibration mode off The CMODE query can also be used at any time to determine if the supply is in calibration mode A 1 indicates calibration mode is on a O indicates calibration mode is off Continue to the next command 2s VHI lt channel gt This command causes the voltage of the specified output channel to go to the high calibration point full scale After the command is sent use the voltmeter to read the actual voltage lt Vhi gt put out by the power supply Continue to the next command 3 VLO lt channel gt This command causes the voltage of the specified output channel to go to the low calibration point voltage offset After the command is sent use the voltmeter to read the actual voltage lt Vlo gt put out by the power supply Continue to the next command 4 VDATA lt channel gt lt Vlo gt lt Vhi gt This command is used to send the actual values measured by the voltmeter in the previous steps to the power supply Refer to Table A 2 for the range of valid voltage readings that can be sent to the supply lt Vlo gt is the voltage in volts that was measured after the VLO command was sent lt Vhi gt is the voltage in volts tha
82. f the calibration procedure To find out if the CMODE is on or off send the following query over the HP IB and address the supply to talk CMODE Remote Operation 79 The supply will respond with a 1 which indicates that CMODE is on or a 0 which indicates that CMODE is off DCPON The DCPON command sets the state of all outputs at power on You can specify if the outputs wake up enabled or disabled when the unit is turned on To enable all outputs at turn on send DCPON 1 To disable all outputs at turn on send DCPON 0 Note that these commands set the output voltage to zero and the output current to a slightly positive value when the OUTPUT OFF command is issued Therefore the constant voltage feedback loop is active and the outputs are in constant voltage mode when programmed OFF Starting with firmware revision A 00 04 and later two additional commands let you set the output current to a slightly negative value when the OUPUT OFF command is issued causing the outputs to be in constant current mode when programmed OFF The benefit of being in constant current mode when the output is off is that if the load impedance and the voltage and current settings are such that the unit is forced into constant current mode at turn on then the current feedback loop will be active during the transition to OUTPUT ON and there will be no output current overshoot due to mode crossover To enable all outputs in constant current mode at
83. fly describes the HP IB interface functions to get you acquainted with remote programming using the HP IB Under Programming Syntax the syntax of all commands the numeric data formats and the programmable ranges for all models are given Initial Conditions highlights the initial values of all the parameters at power on Power Supply Commands will describe all the commands which can be used to program the supply s functions including status reporting error handling protection features and voltage and current programming The power supply commands are summarized in Appendix C The examples are written in a generic form to make adaptation to your controller easy You should be familiar with the use of your controller and its instruction set and how the power supply commands can be incorporated in your controller commands If you are not familiar with the operation of the power supply you are advised to read through Chapters 2 through 4 first HP IB Operation Interface Function Remote control is implemented by the HP IB It enables instructions to be sent from an external computer equipped with an HP IB interface The power supply implements the following IEEE 488 Interface Functions SH1 Source Handshake SRI Service Request AHI Acceptor Handshake RL1 Remote Local T6 Talker PP1 Parallel Poll L4 Listener DC1 Device Clear The source handshake acceptor handshake talker and listener functions are implemented by the interface
84. g States Your power supply has registers that can store up to 10 operating states These states can be recalled in arbitrary order Storing a state involves taking a snapshot of the voltage and current settings that are in effect when the command is received The following example uses stored operating states to set up an output Using this method of setting up outputs saves processing time and facilitates repeating the same commands 10 ASSIGN Ps TO 705 20 OUTPUT Ps OUT1 0 0UT2 0 30 40 OUTPUT Ps VSET1 1 ISET1 1 VSET2 5 ISET2 1 5TO1 50 OUTPUT Ps VSET1 2 ISET 1 2 VSET2 4 ISET2 2 STO2 60 OUTPUT Ps VSET1 3 ISET 1 3 VSET2 3 ISET2 3 STO3 70 OUTPUT Ps VSET1 4 ISET1 4 VSET2 2 ISET2 4 STO4 80 OUTPUT Ps VSET1 5 1SET1 5 VSET2 1 1SET2 5 STOS5S 90 100 OUTPUT Ps CLR 110 FOR State 1 TO 5 120 OUTPUT Ps RCL State 130 WAIT 2 140 NEXT State 150 END LINE 10 Assigns the I O pathname to the power supply LINE 20 Disables output 1 and output 2 LINE 40 80 Stores 5 operating states for output 1 and output 2 in storage registers 1 through 5 Outputs not explicitly programmed will store the settings that are in effect when the store command is received LINE 100 Clears the supply All outputs are enabled and set to the initial power on state 0 volts minimum current setting LINE 110 140 Loops through the sequence of five states with a two second wait between states Programming Outputs Connected In Pa
85. g their supply from a computer The programming examples that follow assume that a computer is connected to the HP IB connector on the rear of your supply see Chapter 2 power is applied and loads are not connected to any of the supply s outputs The examples used are primarily for HP Series 200 computers using HP BASIC language Read the manuals for your particular computer to find out which statements you must use Enter Output Statements The programming statements you use to operate your supply from remote depend on your computer and its language In particular you need to know the statements your computer uses to output and enter information For example the HP BASIC language statement that addresses the power supply to listen and sends the command to the power supply is 38 Getting Started OUTPUT The HP BASIC language statement that addresses the power supply to talk and reads back data from the power supply is ENTER The supply s front panel ADDR annunciator is on when the supply is addressed to talk or to listen Reading the HP IB Address Before you can operate your power supply remotely you need to know its HP IB address The address was displayed during the power on sequence described in Normal Self Test Indications page 35 To see the address press A typical address display is shown in Figure 3 6 EOS gt 1 2 3 4 CV CC UNR OCP ERR RMT ADDR SRO OUTPUT ENBLD Figure 3 6 Typical Address Display Th
86. ge error NOTE Care should be taken to not select the controller address 62 Remote Operation Power On Service Request PON The power supply can request service from the controller when the power is turned on This request can be enabled or disabled by sending a PON command see page 77 When the request is enabled the supply can generate an SRQ at power on or when there is a momentary loss in power You can execute a serial poll to clear the service request Table 5 7 details the conditions under which a PON command will generate an SRQ NOTE The power supply has a non volatile memory in which it stores certain system variables Some of these variables are the calibration constants the present supply address and the present setting of the PON command Programming Syntax The following paragraphs describe the syntax of the device command that is used to program your power supply As shown in Figure 5 1 the device command is a specific part of the program statement that your computer will accept The first part of the statement is computer as well as programming language specific Figure 5 1 shows the structure of a typical programming statement for an HP Series 200 computer If you are using a different computer or programming language refer to your computer programming manual to determine the correct syntax for this portion of the program statement This section of the manual is only concerned with the device command portion the part ins
87. ges Attempting to program voltage or current values that are greater than the maximum programmable values for a given output results in an error message and the values are ignored by the supply Range Selection When a voltage and current are specified each of which is within the maximum programmable value but whose combination lies outside the L shaped operating locus the power supply will automatically select the operating range based on the value of the last VSET or ISET parameter that was programmed The other parameter will automatically be reprogrammed to the maximum rating of the selected range Chapter 5 includes an example of automatic range selection also referred to as range switching Once your power supply output is operating in a given range it will not automatically switch to the other range because of a change in the load The only time an output switches operating ranges is in response to a command from either the front panel or the HP IB that changes the voltage or current settings For the output to switch ranges the voltage or current setting must specify a value that is inside the operating locus of the other range If the value sent is common to both ranges no range switching occurs Protection Features Protective circuitry within the supply can limit or turn off an output in the event of an abnormal condition The activated protection feature can be determined by observing the front panel display area You can also read b
88. ghtened and terminal block covers are replaced before reapplying power 68 Remote Operation Voltage Programming To program voltage send the output channel and the programmed value In the example below output is programmed to 5 V VSET 1 5 The values you send must always be volts For example if you want to program 450 millivolts convert to volts and then send the command VSET 1 45 If the output channel is operating in constant voltage mode CV annunciator on then the actual voltage is the programmed voltage but in CC mode of operation CC annunciator on the programmed voltage is the voltage limit for that output To readback the programmed voltage setting for output 1 send the query VSET 1 and address the supply to talk If you want to know the value of the actual output voltage of output 1 send the query VOUT 1 The results are placed on the HP IB and read into the controller when the supply is addressed to talk NOTE The power supply will round the VSET and ISFT settings to the nearest multiple of their resolution Table 5 4 lists the average resolution of these settings Current Programming To program the current send the output channel and the programmed value in amps In the example below output is programmed to 1 15 amps ISET 1 1 15 The value you send must always be in amps For example if you want to program 95 milliamps convert to amps and then send the command ISET 1 095 If the output chann
89. gisters is given in Chapter 5 The main points of this description are repeated below for continuity in explaining how to use the front panel UNMASK and FAULT keys The mask register which is set by the user is used to specify which bits in the status register are enabled unmasked to set bits in the fault register A bit is set in the fault register when the corresponding bit in the status register changes from 0 to 1 and the corresponding bit in the mask register is 1 Each output channel has its status mask and fault registers arranged as shown in Table 6 1 Local Operation 85 Table 6 1 Bit Arrangement of the Status Mask and Fault Registers Bit Position 7 6 5 4 3 2 Note that bits can be set in an output s fault register only when there is a change in either the status register or the mask register Therefore if a bit is set in the mask register unmasked while the corresponding condition is true in the status register the associated bit will also be set in the fault register The UNMASK key is used to send a decimal number that is the sum of the weights of the bits to be set The decimal number 0 will clear all bits in the mask register so that status register bits cannot set any of the corresponding fault register bits The following example uses the number 9 8 1 to set the OV bit 8 and the CV bit 1 in the mask register of the selected output unmask 9 ENTER This example allows only an OV and
90. gt lt input gt Queries the measurement of the input 1 to 8 to the analog multiplexer on the specified output board See Service Manual VOUT lt ch gt Queries the measured output voltage of the specified output channel see Voltage Programming page 69 The response is a real number The front panel display can be used to monitor the measured output voltage and current of the selected output channel VSET lt ch gt lt voltage gt Sets the voltage of the specified output channel see page 69 VSET lt ch gt Queries the present voltage setting of the specified output channel see page 69 The response is a real number UNMASK lt ch gt lt setting gt Sets the bits in the mask register of the specified output channel to the setting integer from O to 255 The mask register operates in conjunction with the status and fault registers see page 74 UNMASK lt ch gt Queries the present setting of the mask register of the specified output channel see page 74 The response is an integer from 0 to 255 Indicates that the command can be executed from the front panel 108 Command Summary Error Codes and Messages Introduction This appendix describes the HP IB error codes that can be readback to the controller and the error messages that can be displayed on the power supply s front panel A brief explanation of each code and message is also given The error codes and or messages fall into three categ
91. h will fire the SCR crowbar if the voltage exceeds 120 of the maximum rated output The fixed OV circuit will also fire the SCR crowbar if the supply is off line cord disconnected and an external source is supplying voltage which exceeds 120 of the maximum rated output Overcurrent Protection OCP The OCP is a protection feature employed by the power supply to guard against excessive output currents When the output enters the CC mode and the OCP is enabled the OCP circuit down programs the output voltage and disables the output To enable the OCP for output channel 1 send the command OCP 1 1 To disable the OCP send the command OCP 1 0 You can find out the OCP setting by sending the following query and addressing the power supply to talk OCP 1 The response from the power supply is either a 0 to indicate that OCP is off or a 1 to indicate that it is on To reset the output channel after an overcurrent trip you can either disable the OCP and send the reset command or you can reduce the output current below the programmed current and then send the reset command To reset output 1 send the command OCRST 1 NOTE The supply can report a fault condition when an output is in overvoltage or overcurrent Although the OVRST and OCRST commands reenable the output they do not clear the fault register As a housekeeping measure it is advisable to always clear the fault register by querying its value after an OV or OC reset Multiple
92. hannel No 1 HP IB Device Address Getting Data From The Supply The supply is capable of measuring the values of its output parameters in response to queries In this example the query asks the supply to measure the output voltage at output 1 When you send a query from remote the supply does not display the response as it did when you executed the command from the front panel Instead it holds the response in an output buffer The output buffer is a register that holds information until it is read by the computer or is replaced with new information Measure Output Voltage Query OUTPUT 705 VOUT 1 Output Channel No 1 NOTE On an HP Series 200 Computer the A variable must be declared before you do the following steps Refer to your computer s operating manual for more information Use your computer s enter statement to get the response from the output buffer For example execute ENTER 705 A Followed by DISP A The ENTER statement enters whatever is in the supply s output buffer into the computer s A variable The DISP statement displays the A variable s contents on the computer s display Often Used Commands The command set contains over forty commands that allow you to program the power supply in a variety of applications Within this command set however is a small subset of commands that are all you need for most applications These commands are VSET ISET VOUT IOUT OUT OVSET and OCP Each of these co
93. hat this diode will conduct current in excess of the rated current of the output since damage could result Connecting outputs in series provides a greater voltage capability than can be obtained from a single output Because the current is the same through each element in a series circuit outputs connected in series must have equivalent current ratings Otherwise the higher rated output could potentially damage the lower rated output by forcing excessive current through it under certain load conditions Figure 4 13 shows an example of how to connect two outputs in series to a single load with local sensing This configuration applies to both CV and CC operating modes Connecting the load lead of output 2 directly to the V terminal of output 1 completes the series connection between the two outputs Connecting the S terminal of output 2 directly to the S terminal of output 1 and removing the sense jumper between S and V on output 2 compensates for the IR drop in the load lead from output 2 to output 1 OUTPUT 2 V TO S SENSE JUMPER INSTALLED Ta Ta Pa Ta a a O LEREN H OUTPUT 1 SENSE JUMPERS INSTALLED Figure 4 13 Series Connections with Local Sensing CV Operation For CV operation first program the current setting of each output to the desired current limit point Then program the voltage of each output so that the sum of both voltages equals the total desired operating voltage The simp
94. he electromagnetic field is less than 5 gauss NOTE The HP 662xA power supplies generate operating magnetic fields which may affect the operation of other instruments If your instrument is susceptible to operating magnetic fields position it more than 3 inches from the HP 662xA supply Initial Inspection Your instrument was thoroughly inspected and tested before it left the factory As soon as you receive it remove the power supply from its packing case and check to make sure it has not been damaged in shipment Check that there are no broken connectors or keys and that the cabinet and panel surfaces are free from dents and scratches Check the rear panel terminal blocks and front panel display for any cracks If damage is found you should file a claim with the carrier immediately and notify the Hewlett Packard Sales and Service office nearest you Chapter 3 of this manual includes an electrical turn on check out procedure which when carried out successfully will give you a high level of confidence that the power supply is operating in accordance with its specifications Detailed electrical checks complete with verification procedures are included in the Service Manual Keep the original packing materials for the carrier s inspection if there was damage or in case any equipment has to be returned to Hewlett Packard Warranty information is printed on the inside cover of this manual Remember to send a detailed description of the failure and sy
95. he the Scr P to select output being tested 5 Set the voltage to 5 volts by pressing Getting Started 37 6 Check that the display reads approximately 0 volts and the minimum current limit value 0 05 to 0 13A depending upon the model and output see Table 5 4 Also check that the front panel CC annunciator is on indicating that the output is in the constant current mode of operation 7 Set the current to 0 5 A by pressing ee 8 Check that the display reads approximately 0 V and 0 5 A 9 Enable the overcurrent protection circuit by pressing OCP 10 Check that the OCP ENBLD annunciator is on indicating that overcurrent protection is enabled and the display reads OVERCURRENT When in overcurrent the output is disabled 11 Disable the overcurrent protection circuit by pressing OCP 12 Reset the output by pressing OC RST 13 Check that the display reads approximately 0 V and 0 5 A 14 Turn off the supply and remove the jumper from the output terminals Repeat the tests given on pages 37 amp 38 for the other output channel s using the qOUTP UT key SELECT Introduction To Remote Operation The following paragraphs explain the fundamentals of operating the supply remotely from a computer Only a few commonly used programming commands will be discussed Refer to Chapter 5 for a detailed description of all the commands The intent of this discussion is to help first time users to quickly become familiar with operatin
96. hile constant portions or any constants are changed as indicated below Voltage All series specifications referring to voltage are twice the single output specification except for programming resolution which is the same as for a single output 58 Output Connections and Operating Information Current All series specifications referring to current are the same as for a single output except for CC load effect CC load cross regulation CC source effect and CC short term drift which are twice the current programming accuracy including the percentage portion Load Transient Load transient recovery time is the same to within approximately twice the voltage setting band since Recovery Time the output impedances of the series combination add together Output Connections and Operating Information 59 Remote Operation Introduction Chapter 3 introduced you to the basics of remote operation and provided a few simple examples using a Series 200 computer as the HP IB controller This chapter contains all the information required to control your power supply remotely and discusses in greater detail how each of the commands can be implemented The material covered is intended for any controller capable of using the HP IB interface functions mentioned in Interface Function on this page Four major sub sections are discussed These are 1 HP IB Operation 2 Programming Syntax 3 Initial Conditions 4 Power Supply Commands The HP IB section brie
97. icated below For current readback accuracy and temperature coefficient of current readback use the minus current specifications Current All parallel specifications referring to current are twice the single output specification except for programming resolution which is the same for both single output and parallel output operation Voltage All parallel specifications referring to voltage are the same as for a single output except for CV load effect CV load cross regulation CV source effect and CV short term drift Below 2 5 V these are all twice the voltage programming accuracy including the percentage portion CV load effect above 2 5 V could be twice the load effect specification for a single output CV output noise for output voltages less than 2 5 V may be slightly higher than the output noise for a single output Load Transient 350us maximum to recover within 100 mV of nominal value following a load change within the Recovery Time range of 0 to full load 56 Output Connections and Operating Information Series Operation SHOCK HAZARD Floating voltages must not exceed 240 Vdc No output terminal may be more than 240 Vdc from chassis ground Connect in series only outputs that have equivalent current ratings Each output has a reverse voltage CAUTION a a ee protection diode across its output terminals The current conducted by this diode is not internally limited by the output Therefore never connect an output in such a way t
98. icates that the OV and the CV bits in the fault register are set NOTE If the condition s generating the fault s is are removed but the fault register is not read the bit s in the fault register will remain set The Serial Poll Register The serial poll register is an 8 bit register which the supply uses to keep track of its internal operating status and to determine the operating status of each of its outputs Table 5 6 defines each bit Table 5 6 Bit Assignment of the Serial Poll Register Bit Position 3 2 1 0 Bit Weight 8 4 2 1 Meaning FAU 4 FAU 3 FAU 2 FAU 1 Remote Operation 75 The first four bits 0 to 3 in the register tell whether or not a particular output has a fault If there is a fault in one of the outputs then the corresponding FAU bit will be set Thus if output 1 has a fault then FAU 1 will be set In models with only three outputs FAU 4 will always be zero and in two output models FAU 3 and FAU 4 will always be zero The RDY bit is set when processing is complete and is cleared when the supply is processing commands The ERR bit is set when a programming or hardware error occurs and is cleared when the error query ERR is received The error annunciator on the front panel informs the user when this bit is set or cleared The RQS bit is set when the power supply generates a service request and cleared after a serial poll is done see the following paragraph Service Request Generation The PON bit is set at
99. ide the quotes for Series 200 computers with BASIC of the program statement COMPUTER COMMAND DEVICE COMMAND vset 1 10 22 KEYWORD DESTINATION ITEM HP IB SELECT CODE CHEADER CHANNEL AND DATA AND DEVICE ADDRESS Figure 5 1 Typical Program Statement for Series 200 Computers Figure 5 2 shows the possible syntax forms for the device commands that are used to program the power supply Syntax forms for the calibration commands that are discussed in Appendix A are also included The oblong shape at the left of the syntax forms contains the command header which must be entered as shown in Tables 5 1 and 5 2 Commands are accepted in either uppercase or lowercase letters ASCII characters Circles contain characters that must be entered exactly as shown Characters such as a space lt SP gt or a comma are used to separate elements in the command string Characters such as a line feed lt LF gt or a semicolon are used to terminate the command string Rectangles contain parameters that follow the command header lines and arrows indicate the correct paths through the syntax diagrams Numeric Data The power supply will accept numeric data in implicit point explicit point or scientific notation A general syntax diagram for numeric data is included in Figure 5 2 Implicit point notation means that numbers do not contain a decimal point integers for example Numbers written in explicit notation contain a decimal point such as
100. is programmed Note that with remote sensing voltage readback monitors the load voltage at the sense points CABLED TWISTED OR SHIELDED PAIR OPTIONAL BYPASS CAPACITOR AS CLOSE AS POSSIBLE TO LOAD SEE PARA 4 12 FOR CAPACITANCE VALUE Figure 4 5 Remote Voltage Sensing ALLOWED VOLTAGE OP_ACROSS EACH LOAD LEAD 1 VOLT BELOW MAXIMUM VOLTAGE MAXIMUM VOLTAGE RATING OF OUTPUT RATING 20 2V OR 58 5V Figure 4 6 Allowable Load Lead Voltage Drop with Remote Sensing The maximum voltage available at the power supply output terminals during remote sensing see Figure 4 6 is the maximum voltage 20 2 V or 50 5 V rating plus one volt i e 21 2 V or 51 5 V as shown in Figure 4 2 This allows a voltage drop of 0 5 V per load lead or one volt total For lower output voltages refer to Figure 4 2 Remote Sense Connections Remember to turn off the power supply before making or changing any connections on the rear panel terminal blocks Connect the unit for remote sensing by first disconnecting the straps between sense and load terminals Then make your connections as shown in Figure 4 5 Connect the sense leads as close to the load as possible See pages 47 amp 48 for information on selection of load lead wire gauge Best results will be obtained by using the shortest load leads practical It is recommended that you keep your load leads under 14 7 meters 50 feet per lead b
101. layed For example the front panel display in Figure 6 1 shows the VSET function for output 2 set to 1 250 You can change the setting using the numeric entry keys Pressing the number keys will cause the present numeric setting to become blank and be replaced with the new numbers on the display You can use the lt key to erase previous keystrokes if you make a mistake Local Operation 83 FUNCTION SETTING OUTPUT FUNCTION KEYS OUTPUT CHAN 2 LOCAL MODE KEY Ms 24A SYSTEM DC PONER ST La MESA La 2 58 lo a a ENBLD SYSTEM FUNCTION KEYS NUMERIC ENTRY KEYS Figure 6 1 Front Panel Model 6624A shown Pressing the ENTER key will enter the values displayed for the function indicated initiate that function and return the display to the metering mode in which the measured output voltage and current for the selected output are displayed Pressing the ENTER key without entering numbers will result in retention of the previous values and return to the metering mode You can also return to the metering mode at anytime by pressing the METER key Setting Voltage The selected output s voltage is programmed locally using the VSET key For example program the voltage to 5 25 volts by pressing VSET ENTER The front panel display then indicates the actual output voltage and current for the select
102. le 3 1 Controls and Indicators continued OUTPUT Indicate which output channel has been selected for front Annunciators panel control and or display Only one output annunciator can be on at a time Power Supply Status CV Indicates that the selected output channel is in the Annunciators constant voltage mode These five annunciators CC Indicates that the selected output channel is in the indicate the status of the positive constant current mode CC or the negative power supply current limit CC mode UNR Indicates that the selected output channel is unregulated 1 e it is not regulated by CV or CC control loops OCP ENBLD Indicates that the overcurrent protection function for the selected channel is enabled ERR Indicates that a programming or hardware error has occurred and that the ERR bit in the serial poll register has not been cleared Alphanumeric LCD Normally displays the measured output voltage and Display When power is current for the selected channel When programmed from turned on all segments will the front panel the function being programmed e g be displayed for VSET the output channel e g 2 and the present value approximately 2 seconds e g 2 250 will be displayed Error conditions will be spelled out in alpha characters System Control Keys ADDR Displays the power supply s HP IB address You These four control keys can change the address using the numeric entry keys You
103. le assign statement In the programming examples in this appendix the I O path name EPs is used for the power supply The ASSIGN statement that defines the I O path must precede any statements that use the I O path name Therefore instead of using the statement OUTPUT 705 VSET1 5 in the following programs the equivalent OUTPUT Ps VSET1 5 statement is used The examples assume that the power supply is at address 5 and the HP IB interface in the computer is select 7 factory default Voltage and Current Programming The power supply normally functions in one of two modes either constant voltage with current limit or constant current with voltage limit The operating mode is determined by a combination of voltage and current settings and load resistance For example with a 10 Q load connected to output 1 the following program will put output 1 in constant voltage mode at 5 volts out with a 1 amp current limit In this case the output current would be 0 5 A 10 ASSIGN EPs TO 705 20 OUTPUT Ps VSET1 5 1SET1 1 30 END Line 10 Assigns the I O pathname to the power supply Line 20 Sets output voltage and current Note the use of the semicolon to separate multiple device commands If a 4 Q load were used instead of a 10 Q load output 1 would have been operating in constant current mode at 1 amp out with a voltage limit of 5 volts In this case the output voltage would be 4 V Programming with a Series 200 300 Compute97 Voltage and Curr
104. leared 2 The power supply remains addressed to listen 3 The PON bit in the serial poll register is cleared To Clear the power supply send the following command CLR Status Reporting The power supply has the ability to report its internal status to the user whenever it is asked to do so Depending on the type of status the user requested the supply will interrogate the status accumulated status mask or fault registers present in each output The status register can report status independently or it can work together with the mask and fault registers to report a fault The accumulated status register records every status condition the output experienced since the time it was last read Figure 5 3 shows a conceptual model of the operation of these registers OUTPUT t REGISTER STRUCTURE OUTPUT 3 OUTPUT 4 STATUS MASK FAULT REGISTER REGISTER REGISTER ACCUMULATED STATUS SERIAL REGISTER POLL REGISTER NOT USED IN ALL MODELS Remote Operation 73 Figure 5 3 Functional Relationship of Status Registers The supply has one serial poll register which services all outputs and provides the user with other power supply status related information as discussed on page 75 Status Register Each output channel of the power supply maintains its present status in an 8 bit register This status register reports the status of the output channel whenever it is queried A 1 in an
105. lest way to accomplish this is to program each output to one half of the total desired operating voltage Both outputs will operate in CV mode Output Connections and Operating Information 57 CC Operation For CC operation the current setting of each output must be programmed to the desired operating current The sum of the voltage settings determines the voltage limit point As an example one way to program the voltage of the output is to set the voltage of each output to one half of the total voltage limit point Then at load voltages less than one half of the total voltage limit point one output will operate in CC mode while the other output will be conducting through its internal reverse voltage protection diode At load voltages greater than one half the total voltage limit point the output that was in CC mode will change to CV mode while the output that was conducting through its diode will regulate the current in CC mode and provide the balance of the voltage required by the load Note that the total load voltage can be found by adding the results of reading back the individual series outputs only when neither reverse voltage protection diode is conducting When this diode is conducting the corresponding output has reverse voltage across it so that its voltage readback may not be accurate When an output is conducting through its reverse voltage protection diode the output will have a reverse voltage across its output terminals with the
106. measured by the voltmeter across the shunt resistor Note that Ihi is in amps since the voltmeter returns volts and Shunt _ resistor is in ohms LINE 430 Sets the current of the specified output to the low calibration point LINE 440 Sets the variable Ilo to the output current as measured by the voltmeter across the shunt resistor LINE 460 Sends the measured data in amps to the power supply for the specified channel LINE 480 Checks for errors See line 280 LINE 500 Set output voltage to 0 so that output connections may be safely moved LINE 520 530 Loops to Start_loop if the user has more outputs to calibrate otherwise continues LINE 550 Stores the calibration constants by turning off the power supply calibration mode LINE 570 600 Clears the supply and ends the main program LINE 630 Defines the user defined function FNDvm LINE 640 Brings in the COM block Instr LINE 650 Waits 02 seconds for the supply to settle at the calibration points LINE 660 670 Takes a reading from the voltmeter LINE 680 Returns the voltmeter reading to the appropriate variable within the main program LINE 690 Ends the user defined function FNDvm LINE 710 Defines the user defined function FNPs _ err LINE 720 Brings in the COM block Instr LINE 730 740 Queries the power supply for any errors LINE 750 If an error occurred the computer reports the error LINE 760 Returns the error number to the appropriate place within the main p
107. ming delay will delay the onset of certain fault conditions and prevent the power supply from registering a fault when these conditions are true When the delay is in effect the CV CC CC and UNR bits of the status register are masked and cannot communicate with the mask and fault registers and the OCP function This will prevent the supply from registering a fault should any of these bits become set during the delay period Reprogramming delay is initiated when any of the following functions are executed VSET ISET RCL OVRST OCRST OUT on off At power on reprogramming delay is set to 20 mS You can specify new values between 0 and 32 S in steps of 4 mS If you specify a value which is not a multiple of 4 mS the supply will round off the set value to the nearest 4 mS multiple To program a new value of 80 mS in output 2 for example send the following DLY 2 08 If you send a value outside the 0 to 32 S range you will get a programming error You may use the programming response times in the specifications table to give you an idea of a typical delay setting However the appropriate delay setting will also depend on load capacitance load resistance and current limit setting See page 51 for output capacitor considerations To query the reprogramming delay setting of a particular output channel send the following query DLY 2 using output 2 as an example and address the supply to talk The response will be a numeric value between 0 and
108. mmands is briefly discussed in the following paragraphs to help you get started in programming your supply To know more about these commands refer to Chapter 5 Voltage and Current Programming You can send voltage and current values to the power supply directly in volts or amps The following examples use voltage and current values that are within the range of any output that the power supply provides 40 Getting Started To set the voltage of output to 5 volts send OUTPUT 705 VSET 1 5 To set the current of output 2 to 450 milliamps send OUTPUT 705 ISET 2 450 Output Voltage and Current Measurement You can instruct the supply to measure the actual output voltage and current at a specified output using the VOUT and IOUT queries respectively To measure the output voltage at output 1 send OUTPUT 705 VOUT 1 To get the measurement from the output buffer send ENTER 705 A DISP A The computer should display a reading of approximately 5 volts To measure the output current at output 2 send OUTPUT 705 IOUT 2 To get the measurement from the output buffer send ENTER 705 A DISP A Output On Off You can turn a specified output on or off Individual outputs can be controlled as shown below To turn off output 1 send OUTPUT 705 OUT 1 0 When an output is turned off it is set to O volts and to the minimum current limit value To turn on output 1 send OUTPUT 705 OUT 1 1 When an output is turned on it will re
109. mptoms when returning the power supply for service Your Hewlett Packard Sales and Service office will furnish the address of the nearest service office to which the instrument can be shipped Location and Cooling Your power supply can operate without loss of performance within the temperature range of 0 to 55 C measured at the fan intake The fan located at the rear of the unit cools the supply by drawing air in through the openings on the rear panel and exhausting it through openings on the sides Using Hewlett Packard rack mount kits will not impede the flow of air Because the power supply is fan cooled it must be installed in a location that allows sufficient space at the rear and the sides for adequate circulation of air Either side may be restricted to have as little as 1 inch 25 mm space Figure 2 1 gives the dimensions of the power supply cabinet These dimensions apply to all five models The cabinet has plastic feet that are shaped to ensure self alignment when stacked with other Hewlett Packard System II cabinets The feet may be removed for rack mounting The power supply can be mounted in a standard 19 inch rack panel or enclosure Rack mounting accessories for this unit are listed on page 12 under Options of Chapter 1 Complete installation instructions are included with each rack mounting kit Instrument support rails are required for non stationary installations These are normally supplied with the cabinet and are not in
110. n the line voltage setting of your supply Table 2 2 gives the HP part numbers for the fuses that should be used with specific line voltages 26 Installation leetererlo o olleke INTAKE ERMINAL BLOCK geleele PLASTIC COVE HP 86624 2888 ERMINAL BLOCK SCREW 3 5 X B 6 X Emm Figure 2 2 Rear Panel Detail 6624A Shown Table 2 2 Line Fuses Line Voltage Fuse Needed HP Part Number for 1 4 X 1 1 4 in fuses only 100 120 V 8A 2110 0342 220 240 V 4A 2110 0055 Note All fuses are rated for 250 V VOLTAGE SELECT P C BOARD Figure 2 3 Line Module Detail Installation 27 Power Cord The power supply is shipped from the factory with a power cord that has a plug appropriate for your location Figure 2 4 shows the standard configuration of plugs used by Hewlett Packard Below each drawing is the HP part number for the replacement power cord equipped with a plug of that configuration If a different power cord is required contact the nearest Hewlett Packard Sales and Service office For your protection the National Electrical Manufacturer s Association NEMA recommends that the instrument panel and cabinet be grounded This power supply is equipped with a three conductor power cord the third conductor being the ground The power supply is grounded only when the power cord is plugged into an appropriate receptacle Do not operate this power supply witho
111. nal block cover away from the terminal block To reinstall the cover align it over the terminal block and gently press it into position until the locking tab engages SHOCK HAZARD Turn off ac power before making rear panel connections All wires and straps must be properly connected with terminal block screws securely tightened Replace terminal block covers before reapplying power Each rear terminal block has six M3 5 x 0 6 x 6 mm screws for attaching wires see Figure 2 2 Load connections to the supply are made at the V and V terminals on each terminal block Do not connect unterminated wires to the load terminals Wires used for load connections must be properly terminated with termination connectors securely attached Remember to replace the impact resistant plastic covers HP P N 06624 20007 over the terminal blocks after making connections 46 Output Connections and Operating Information S 1 2 Vor A APPROX 8 2 9 VOLTS APPROX 8 4 1 APPROX 227 2 5 2 0 1 5 1 0 5 our Tout CAMPS AMPS 4 W LOW VOLTAGE 4 W HIGH VOLTAGE 1 2 Y APPROX 9 19 VOLTS OUT VA 1 2 Vout APPROX 8 27 VOLTS Tour lout AMPS AMPS 8 W LOW VOLTAGE B W HIGH VOLTAGE Figure 4 3 Typical Downprogramming Characteristic Below 2 0 V Wire Size Selection FIRE HAZARD Select a wire size large enough to carry short circuit current without overheating Two factors must be considered when selecting wire size for load connections c
112. nel gt This command causes the current of the specified output channel to go to the low calibration point current offset After the command is sent use the voltmeter to read the voltage drop across the current shunt resistor Divide this reading by the shunt value to derive the actual current in amps lt Ilo gt put out by the supply Continue to the next command 8 IDATA lt channel gt lt HO gt lt Ihi gt This command is used to send the actual current values derived in steps 6 and 7 to the power supply Refer to Table A 2 for the range of valid current readings that can be sent to the supply lt Ilo gt is the current in amps that was put out by the supply after the ILO command was sent lt Ihi gt is the current in amps that was put out by the supply after the IHI command was sent The power supply uses these values to calculate the current and current readback correction constants of the specified output 92 Calibration Procedures Repeat commands two through eight for any other outputs that must be calibrated on your power supply After you have completed calibration of all outputs turn the calibration mode off by sending the CMODEO command see step 1 to the power supply The correction constants are stored in memory at this time Calibration Program The following calibration program can be used as is provided you have an HP Series 200 computer with the BASIC programming language and an HP 3456A voltmeter The calibr
113. ng of the specified output channel see page 69 The response is a real number OCP lt ch gt lt on off gt Enables the overcurrent protection circuit for the specified output channel This circuit when enabled causes the output to go to the off state when the output is in the CC mode On off is a 1 to turn on enable or a O to turn off disable the circuit see page 72 Indicates that the command can be executed from the front panel 106 Command Summary Table C i Command Summary continued OCP lt ch gt OCRST lt ch gt OUT lt ch gt lt on off gt DCPON lt on off gt OUT lt ch gt OVSET lt ch gt lt overvoltage gt OVCAL lt ch gt OVRST lt ch gt OVSET lt ch gt PON lt on off gt RCL lt reg gt ROM SRQ lt setting gt Queries the overcurrent protection circuit on off status for the specified output channel see page 72 Response is either a 1 on or a 0 off The OCP ENBLD annunciator on the front panel displays the on off status of the OCP circuit for the selected output Returns the specified output channel to the previous settings after it had been turned off by the overcurrent protection circuit see page 72 Turns the specified output channel on or off On off equals 1 to turn the output on and equals 0 to turn the output off see page 71 Sets the state of the outputs at power on For on off 0 all outputs will be off
114. nnnn cnn ncciannncnnnss 104 Command Summary A A RA 105 Error Messages Intro cht ori RARA ds 109 Power On Self Fest Messages e I ax isus sextet steslsets te ces ep it sapa oeiee Piee Kee ccvsstee piesedhpetetbeeprtete RiPS Sees a 109 Error Responses nvcisc tine aioe dice ie te ieee ei Ua eae eae ees 109 SA O NN 109 Manual Backdating Tntrod cton sita ido e 113 ES A NN 113 Addendum Generally Applicable Annotations CE 92 Product Specific Annotations ooooocccnonncnonnc n eononcnannnnanacinnoss 114 HP Sales and Support Office GOMPACES Sa tt istics ch Re acres cen chee es ER ce Cae ahd CaN oe CARERS oe UE Es wah weds see e ict esta ae eS 115 General Information Introduction This chapter contains a general description of your power supply as well as its performance specifications Information about options accessories and HP IB cables is also provided This manual describes all five models in the HP 6621 A 6624A and 6627A power supply family Unless stated otherwise the information in this manual applies to all of these models Information that is specific to one model only is identified as such in this manual Safety Considerations This product is a Safety Class 1 instrument which means that it is provided with a protective earth terminal This terminal must be connected to a power source that has a 3 wire ground receptacle Review the instrument and this manual for safety markings and instructions before operation
115. nt panel Each power supply model contains one output board for each output that it provides Models 6624A and 6627A contain four 40 watt output boards Model 6623A contains two 40 watt output boards and one 80 watt output board Models 6621A and 6622A each contain two 80 watt output boards HP IB Board The HP IB board provides the interface between the user and the multiple outputs of the power supply Each output board is actually an output channel that can be individually selected and controlled over the HP IB or from the supply s front panel Circuits on the HP IB board interpret commands from the HP IB or from the front panel to control the selected output General Information 13 The HP IB board also processes measurement and status data received from the output boards This data may be read back over the HP IB and or displayed on the supply s front panel The power supply has no potentiometers Each output is individually calibrated over the HP IB using calibration commands see Appendix A Correction factors are calculated by the power supply during calibration and are stored in a non volatile memory which is located on the supply s HP IB board The supply contains no batteries Output Boards The output boards are linear de power supplies Each isolated output has the L shaped operating curve described in Description page 12 and Figure 1 1 The ac input to each output board is rectified and applied to a regulator circuit Each outp
116. number that is not within the valid range the ERR annunciator will come on You can display the error message by pressing the ERR key In this case the error message NUMBER RANGE will be displayed Errors generated either locally from the front panel or remotely from the HP IB computer can be displayed by pressing the ERR key only when the supply is in the local mode Pressing the ERR key also clears the error bit so if you press ERR again the message NO ERROR will appear All error codes and associated display messages are listed in Table 5 8 Storing and Recalling Voltage and Current Settings for All Outputs As described on page 72 the power supply has 10 internal registers for storing voltage and current settings of all outputs At power on each location contains zero volts and the minimum current limit see Initial Conditions page 68 The STO and RCL keys allow you to store and recall voltage and current settings for all your output channels from any of the 10 internal registers numbered 1 through 10 For example you can store the present settings of voltage and current for all the output channels in internal register 2 by pressing You can change the settings of any of your supply s outputs any number of times as required and then program them to the settings stored in internal register 2 by pressing The internal register will not retain the settings when power is turned off When power is turned off and then on again each internal
117. o an electrical ground safety ground at the power outlet For instruments designed to be hard wired to the ac power lines supply mains connect the protective earth terminal to a protective conductor before any other connection is made Any interruption of the protective grounding conductor or disconnection of the protective earth terminal will cause a potential shock hazard that could result in personal injury If the instrument is to be energized via an external autotransformer for voltage reduction be certain that the autotransformer common terminal is connected to the neutral earthed pole of the ac power lines supply mains FUSES Only fuses with the required rated current voltage and specified type normal blow time delay etc should be used Do not use repaired fuses or short circuited fuseholders To do so could cause a shock or fire hazard DO NOT OPERATE IN AN EXPLOSIVE ATMOSPHERE Do not operate the instrument in the presence of flammable gases or fumes KEEP AWAY FROM LIVE CIRCUITS Operating personnel must not remove instrument covers Component replacement and internal adjustments must be made by qualified service personnel Do not replace components with power cable connected Under certain conditions dangerous voltages may exist even with the power cable removed To avoid injuries always disconnect power discharge circuits and remove external voltage sources before touching components DO NOT SERVICE OR ADJUST ALONE
118. o the supply resulting in simpler programming Voltage and current settings can be sent directly to the specified dual range output in volts and amps Service can be requested from your power supply for up to ten reasons The supply responds to a serial poll by identifying the output on which the fault occurred Self contained measurement and readback capability eliminate the need for externally scanning the outputs using a separate DVM Upon command the supply will measure its output voltage or current and return the value on the HP IB The following functions are implemented via the HP IB Voltage and current programming Voltage and current measurement and readback Present and accumulated status readback Programmable service request mask Programmable overvoltage and overcurrent protection 12 General Information Storage and recall of programmed voltage and current values for all outputs Queries of programmed functions or settings Output enable or disable Programming syntax error detection Programmable delay time for service request and OCP mask Voltage current and overvoltage calibration HP IB interface selftest Message display capability on the front panel Output connections are made to rear panel screw terminals Either the positive or negative output terminal can be grounded or the output can be floated up to 240 Vdc including output voltage from chassis ground Output voltage can be locally or remotely sensed
119. oint The voltage of each output can then be programmed so that the sum of the voltages equals the desired voltage limit point An easy way to do this is to set each output to one half of the desired limit point Refer to Chapter 4 for more information on series operation Figures 4 13 and 4 14 are examples of series configurations which apply to both the CV and CC operating modes Note the sense lead connections shown in Figure 4 14 The following example programs outputs and 2 which are connected in a series configuration 10 ASSIGN Ps to 705 20 INPUT ENTER THE DESIRED CURRENT LIMIT POINT I 30 INPUT ENTER TEIE DESIRED VOLTAGE LIMIT POINT V 40 OUTPUT s CLR ISET1 1 jISET2 5I 50 OUTPUT Ps VSET1 V 2 VSET2 V 2 60 END LINE 10 Assigns the I O pathname to the power supply LINE 20 Enter the desired current limit point LINE 30 Enter the desired voltage limit point LINE 40 Clears the supply and sets the current of both outputs to the desired current limit point LINE 50 Sets the voltage of each output to one half of the desired voltage limit point so that the sum is the desired voltage limit point 104 Programming with a Series 200 300 Computer Command Summary Introduction Table C 1 provides an alphabetical listing and a brief description of each command that can be sent to the HP 6621A 24A and 6627A power supplies All of the commands can be executed remotely over the HP IB Many of the commands can also be e
120. ollowing program uses input statements to program the voltage and current settings of output and output 2 10 ASSIGN Ps TO 705 20 INPUT ENTER A VOLTAGE FOR OUTPUT 1 V1 30 INPUT ENTER A CURRENT LIMIT FOR OUTPUT 1 I1 40 INPUT ENTER A VOLTAGE FOR OUTPUT 2 V2 50 INPUT ENTER A CURRENT LIMIT FOR OUTPUT 2 12 60 OUTPUT Ps VSET1 V1 ISET1 311 3 VSET2 V2 ISET2 12 70 END Line 10 Assigns the I O pathname to the power supply Line 20 30 Enter voltage and current values for output 1 Line 40 50 Enter voltage and current values for output 2 Line 60 Sets the voltage and current of outputs 1 and 2 to the values entered into the variables The previous example explained the use of the comma inside the quotes and the semicolon that precedes the variable The semicolon that follows the variable suppresses the comma that the computer would normally send to the power supply if a comma were used as a separator after a numeric item The leading semicolons inside the quotes separate multiple device commands the VSET commands from the ISET commands in this case Voltage and Current Readback Reading back data from the power supply requires two statements First an output statement is used to query the power supply A list of queries appears in Table 5 2 The power supply responds to the query by entering the requested data into a buffer Next an enter statement is used to read the data from the buffer on the power supply into a v
121. on of the supply s front panel controls and indicators and describes how to turn on the supply and to check it s operation An introduction to remote operation over the HP IB is also given to help a first time user get started quickly Chapter 4 Output Connections and Operating Information Chapter 4 contains information about making connections to the supply s output terminals General operating information is also provided Chapter 5 Remote Operation Chapter 5 contains all of the information required to operate the supply remotely via an HP IB computer All of the commands that can be used to program the supplies are described Chapter 6 Local Operation Chapter 6 contains instructions on using all of the front panel controls and indicators Appendix A Calibration Procedure Appendix A contains programming steps and procedures that are required to calibrate your power supply It is recommended that the power supply be calibrated yearly Appendix B Programming with Series 200 Computer Appendix B contains Series 200 300 Computer programming examples in HP extended BASIC language for your Power Supply s most frequently used functions Appendix C Command Summary Appendix C contains an alphabetical listing of all commands that can be sent to a supply Appendix D Error Messages Appendix D contains a listing and brief explanation of all error codes and messages for all programming and hardware errors Appendix E Manual Backdating A
122. on or off Response is either a 1 on or O off see page 79 DLY lt ch gt lt delay gt Sets the reprogramming delay for the specified output channel This delay is used to mask the CV CC CC and UNR status bits from the fault register and the OCP function for the specified delay period 0 to 32 seconds The delay time is initiated after a VSET ISET OUT RCL OVRST or OCRST command is sent see Reprogramming Delay page 78 DLY lt ch gt Queries the present reprogramming delay of the specified output channel see page 78 The response can be a real number from 0 000 to 32 seconds e g 450 seconds DSP lt on off gt Turns the power supply s front panel display either on or off see page 78 On off equals 1 to turn the display on or a 0 to turn it off Indicates that the command can be executed from the front panel Command Summat 5 Table C i Command Summary continued Queries the present status of the display see page 78 Response is either a 1 on or a 0 off DSP XXXXXXXXXXXX Puts the quoted string on the power supply s front panel display see page 79 Only numerals upper case letters and spaces are allowed 12 characters max in the quoted string Queries the present programming or hardware error see page 79 An error code number is returned over the HP IB to identify the error In the local mode pressing the ERR key will cause the appropriate error message not the error cod
123. onductor temperature and voltage drop To satisfy safety requirements load wires must be heavy enough not to overheat while carrying the short circuit output current of the unit Table 4 1 lists the current carrying capacity ampacity for various sizes of stranded wire Note that the minimum wire size required to prevent overheating may not be large enough to prevent OV trip and to maintain good regulation Under most conditions the load wires should be heavy enough to limit the voltage drop to no more than 1 0 V total see Figure 4 6 With remote sensing load regulation is degraded ImV per 200 mV in the V output load lead see page 50 On the 40 W low voltage outputs when the output voltage is set to 7 V there is no voltage drop Output Connections and Operating Information 47 available in the load leads for prolonged operation into a 5 A load during ac low line at high ambient temperature conditions There is a similar stipulation for 80 W low voltage outputs at 10 A under the same conditions as above See Figure 4 2A for worst case voltages available at the output terminals Table 4 1 Stranded Copper Wire Ampacity and Maximum Wire Lengths to Limit Load Lead Voltage Drop Ampacity Per Wire Amps Resistivity Max Length to Limit Voltage to 1 V Per Lead Wire Size 2 Wire Bundled 4 Wire Bundled 5A 10A 20A AWG Q ft feet 20 7 8 6 9 0 0102 20 10 5 18 14 5 12 8 0 0064 30 15 7 5 16 18 2 16 1 0 0040 25 12 5 14 29 3 25 9 0 0025 40 20 12
124. onnect a 40 W high voltage and a 40 W low voltage output together because they have different voltage and current ratings As an example Figure 4 11 shows how to connect two outputs in parallel to a single load with local sensing This configuration applies to both CV and CC operating modes Connecting the load leads of output 2 directly to the V and 54 Output Connections and Operating Information V terminals of output 1 keeps the total length of the load leads to a minimum and reduces the number of wire connections that must be made at the load itself Connecting the S and S terminals of output 2 directly to the sense terminals of output 1 compensates for the IR drop in the interconnecting load leads CV Operation For CV operation one output must operate in CC mode and the other output must operate in CV mode Although each output operates independently of the other the output that is operating in CV mode will be controlling the voltage regulation of both outputs Setting the output voltages as outlined in the following paragraph and configuring the outputs as shown in Figure 4 11 will allow output to operate in CV mode and output 2 to operate in CC mode UTPUT 2 SENSE JUMPERS REMOVED UT 1 SENSE JUMPERS INSTALLED Figure 4 11 Parallel Connections with Local Sensing To assure that output 2 will be operating in CC mode you must program o
125. ons and Operating Information 45 A fixed overvoltage threshold of approximately 120 of the maximum rated output voltage is built into each output Because the fixed overvoltage circuit is biased from the output terminals it can be activated and provide protection even when the supply is not connected to the ac power line The OVRST command restores the programmed voltage and current values and clears the OV once the cause of the overvoltage has been eliminated OVERCURRENT when the overcurrent protection feature is enabled and the output is sourcing current and enters the CC operating mode the output will be disabled set to zero volts and minimum current and the word OVERCURRENT will appear on the front panel display In addition the OC status bit is set for that output The OCRST command restores the programmed voltage and current values and clears the OC once the cause of the overcurrent condition has been eliminated Refer to Chapter V for programming details UNREGULATED OUTPUT the supply informs the user when output regulation is not guaranteed This can occur when attempting to sink excessive currents below 2 5 volts or when operating outputs in parallel The UNR annunciator on the front panel and the UNR bit in the status register indicate that the specified output is unregulated Line voltage dropout or an incorrectly set ac power module can also cause the output to become unregulated If line voltage dropout continues the supply shut
126. ories Power on Self Test Messages responses to the ERR query and responses to the TEST query Power On Self Test Messages The applicable message listed in Table D 1 is displayed on the supply s front panel if the corresponding function has failed the power on self test No error code numbers can be returned for these errors If any of these error messages appear refer to the Troubleshooting section in the Service Manual Error Responses Table D 2 describes the error codes and messages that can be generated for various programming calibration and hardware errors The error codes can be read back over the HP IB in response to the ERR query The applicable error message is displayed on the supply s front panel when the ERR key is pressed Sending the ERR or pressing the ERR key clears the error Test Responses Table D 3 describes the codes that can be read back over the HP IB in response to the TEST query The TEST query initiates a self test of the supply Table D I Power On Self Test Error Message TIMER FAILED The timer on the HP IB board failed 8291 FAILED HP IB control chip on the HP IB board failed CV DAC CH lt ch gt The voltage DAC on the specified output board failed CC DAC CH lt ch gt The current DAC on the specified output board failed OV DAC CH lt ch gt The overvoltage DAC on the specified output board failed FUSE CH lt ch gt The return fuse on the specified output board is opened HDW ERR CH l
127. ply to the local mode provided that the local lockout command has not been received from the computer by pressing the LCL key A change between the local and remote modes or vice versa will not result in a change in the power supply outputs Refer to Chapter 6 for additional details on using the LCL key and operating the supply in the local mode 42 Getting Started Output Connections and Operating Information Introduction This chapter explains how to make connections to the output terminals located on the rear of your power supply Some general operating information is included in this chapter to help you understand how the power supply operates under various load conditions This information applies whether you are operating the supply via the front panel or the HP IB Output Ranges Figure 4 1 identifies the output combinations that are available on the power supply Each output can operate as a constant voltage CV or constant current CC source over a wide variety of output voltage and current combinations In addition each output has an active downprogrammer which operates at currents up to approximately 110 of the maximum positive current rating of the output This means that each output can actively sink as well as source its maximum rated output current At voltages below 2 5 V a downprogramming resistor continues downprogramming until the voltage reaches approximately zero volts OUTPUT 2 82W OUTPUT 2 BAN LOW VOLTAGE HIGH VOLTA
128. ppendix E contains backdating information for units with Serial numbers lower than those listed on the title page Table Of Contents General Information Tntroducthonie csstecciesiccecaestasensieveitak cdisiaeeduyices cdavdealedeyices cles cendedeyacsa dina olaylavecdundevbedavieveelerdeveodatleveutei gerbe 11 Safety CONSI AO a een Aire td E ENERE PEEP RASSIE EEREN 11 Instrument and Manual Identification cccccecesccceessecceeceneeeeeeeeeeceenaeeesseneeeescaeeeceenaeeeeseaeeeeesnneeeeeees 11 OPUS O NON 11 ACCESSOTIOS ANTAS 12 IB e ontos o ES O EE ROE A S E A E EA E A 12 Basic Oper tlOM aiii 13 HP TB Borra AA E A A AAA oe does A 13 Output BoardSe isini aa da ti tei edit 14 SPECIE CALL A ote A pints eke stepbes A tet DN EN E NN EE E ENO 15 Qualifying Conditions eiin tt 15 DGG ONS 3 52 A A ON EAE E 15 Installation Introd ct Onis vs s NO 25 ninal Inspections a a a a a vba neste AN a e a 25 Location and Cooling caminando tdiaib s 25 Input Power Requirements resists ntah eee cava stes sung eheee ne pa ease Eoee eae pe aE paaa po e E neh ESen ENEE a 26 Eine Fut aia 26 ONE a o a PERSE EA A at Ea ie 28 Line Voltage Conversions iaa OR r ete PL e a aoe 28 HP IBAnit erface COMO vital ideada 29 Getting Started Introduction siener a iii iaba 31 Front Panel Controls and Indicators cccccsccccesescceceescceceeeceeceeneceeceeeeeceseaeeesceneeeeseaeeeeeenaeeeesenneeeeeens 31 Turning On Your Supply sicisics Gehl a vaso
129. rallel Only outputs that have equivalent voltage and current ratings can be connected in parallel CAUTION me 2 i When programming outputs that are connected in parallel it is convenient if you first know if you will be operating in CC or CV mode Refer to Chapter 4 for more information on parallel operation 102 Programming with a Series 200 300 Computer CC Operation Programming for CC operation is straightforward Program each output to the desired voltage limit point Then program each output to supply half of the total desired operating current Both outputs will operate in CC mode Note that the total desired current cannot exceed the combined current capability of both outputs Figures 4 11 and 4 12 are examples of parallel configurations These configurations apply to both CV and CC operating modes Note the sense lead connections 10 ASSIGN Ps TO 705 20 INPUT ENTER VOLTAGE LIMIT V 30 INPUT ENTER OPERATING CURRENT Oc 40 C Oc 2 50 OUTPUT Ps CLR VSET1 V ISET1 C VSET2 V ISET2 C 60 END LINE 10 Assigns the I O pathname to the power supply LINE 20 30 Enter the voltage limit and operating current LINE 40 Divides the total current requirement by 2 LINE 50 Clears the supply and sets each output to supply half of the desired operating current at any voltage up to the desired voltage limit CV Operation For CV operation one output must operate in CC mode and the other output must operate in CV mod
130. rce voltage within rated values Expressed as a percentage of setting plus a constant Cross regulation Maximum steady state change in the regulated output parameter due to a change in load resistance on any other output s Programming accuracy Calibration temp 5 C Maximum difference between the programmed value and the actual output Expressed as a constant plus a percentage of the setting Readback accuracy Calibration temp 5 C Maximum error in reading back an output parameter Expressed as a constant plus a percentage of the reading Output response time Beginning at the time the power supply has finished processing a VSET command change output voltage the maximum time for the output voltage to settle to within a settling band about the final value from any specified operating point This value must be added to the command processing time to obtain total programming time see Figure 1 3 Time constant is the maximum time required for the voltage to reach 63 of its final value Temperature coefficient Maximum change in the regulated output parameter per C change in ambient temperature after a 30 minute warmup Expressed in parts per million plus a constant per C plus a constant for readback temperature coefficient Long Term Drift Maximum change of regulated output voltage or current during an 8 hour period following a 30 minute warmup with all influence and control quantities maintained constant Expressed as a
131. rogram LINE 770 Ends the user defined function FNPs _ err Calibration Procedures 95 Programming With A Series 200 300 Computer Introduction The purpose of this appendix is to serve as an introduction to programming your power supply with an HP Series 200 300 computer using the HP extended BASIC language Examples are included that employ some of the most frequently used functions These examples have been written so that they will run on any one of the five HP 6621A 6624A and 6627A model power supplies The values used in the examples 5 V and 1 A for instance are within the operating locus of all outputs on all models The examples program only channels one and two because all five models contain at least two channels outputs You must be familiar with the BASIC language to understand the examples If you do not recognize a programming statement look up the keyword in the BASIC Language Reference document that was supplied with your computer and look up the device command in Chapter 5 of this manual Questions about program structure and selection are discussed in the BASIC Programming Techniques manual I O Path Names Throughout this appendix I O path names are used in place of interface and device select codes In a large program I O path names simplify changing the address of an instrument if necessary Reading and writing the program is easier as well The 1 O path name can be carried in a common block and changed by a sing
132. rogrammed is outside of the existing range the supply will automatically switch ranges A sequence of examples are given on the next page to illustrate this operation Output 1 used in the examples is a 40 W Low V output Example 1 VSET 1 5 ISET 1 2 This example programs output 1 to 5 V and 2 A These values are in the quadrant of the characteristic curve which has voltage and current boundaries common to both high and low operating ranges 70 Remote Operation Example 2 VSET 1 20 Now output 1 is in the high range programmed to 20 V and 2A Example 3 VSET 1 5 ISET 1 3 Output 1 is now in the low range programmed to 5 V and 3A Example 4 VSET 1 10 Now output 1 is in the high range and the current is automatically scaled back from 3 A to the lower current limit of 2 06 A The output is operating in the same range as that of Example 2 Example 5 VSET 1 20 ISET 1 3 The ISET command will cause the voltage to be scaled back to the low range limit of 7 07 V and the output will operate within the boundaries of the low range as in Example 3 NOTE When the range is automatically switched as in examples 4 and 5 the coupled parameter bit CP in the status register see Table 5 5 is set to indicate that range switching occurred Output On Off The OUT command disables enables an output channel of the power supply It will not disturb any other programmed function nor will it reset the protection circuits You can control individual outpu
133. rvice Manual Reposition the jumper and carry out self test if this is desired Table D 3 TEST Responses Explanation No errors were detected The timer on the HP IB board failed self test Refer to the Troubleshooting Section in the Service The RAM on the HP IB board failed self test Refer to the Troubleshooting Section in the Service Manual Note that if this failure occurred at power on it cannot be displayed on the front panel The ROM on the HP IB board failed self test Refer to the Troubleshooting Section in the Service Manual Note that if this failure occurred at power on it cannot be displayed on the front panel Error Codes and Messages 111 Manual Backdating Introduction The backdating information in this section applies to units that have the following serial numbers HP Model 6621A serials 2611A 00101 to 01680 HP Model 6622A serials 2611A 00101 to 02090 HP Model 6623A serials 2611A 00101 to 02230 HP Model 6624A serials 2550A 00101 to 06720 HP Model 6627A serials 2751A 00101 to 00840 Make Changes On page 28 replace the information in Line Voltage Conversion paragraph under steps number 2 3 and 4 as follows 2 To open the line module push against the tab on the line module in the direction of the ac input socket 3 Remove the voltage selector card from its receptacle This card is about one inch square and has a red notch in each of its four edges 4 To select a voltage insert the card into its re
134. s activated the output is shorted and the message OVERVOLTAGE will appear on the front panel display The selected output s overvoltage setting is programmed locally using the OVSET key For example program the overvoltage to 10 5 volts by pressing ovser 1 o C Cs enter Resetting Overvoltage Protection The condition that caused the OV must first be cleared and then the output can be returned to its previous state by pressing the OVRST key Enabling Disabling Overcurrent Protection The overcurrent protection feature guards against excessive output currents When the output goes into the CC mode and OCP is enabled the OCP circuit is activated which downprograms the output voltage and disables the output For this condition the message OVERCURRENT appears on the front panel display The selected output s overcurrent protection feature can be turned on and off from the front panel The OCP key toggles the selected output s overcurrent protection circuit on and off When it is on enabled the OCP ENBLD annunciator will be on Resetting Overcurrent Protection The condition that activated the OCP circuit must first be cleared then the output can be returned to its previous state by pressing the OCRST key Displaying the Contents of the Fault Register Each output channel has a fault register which can be used in conjunction with the status and mask registers to report a fault condition A detailed description of these re
135. s down and will return to the power up condition when normal line voltage is restored OVERTEMPERATURE shuts down the linear pass and downprogrammer of the output that has reached an unsafe operating temperature Operation of the other outputs is unaffected An overtemperature can occur because of excessively high ambient temperature a blocked fan or insufficient space at the sides for adequate air circulation When an overtemperature condition occurs the word OVERTEMP appears in the front panel display and the OT status bit is set This circuit resets automatically and restores the output approximately 30 seconds after the temperature drops sufficiently for safe operation ERROR if the power supply receives an invalid command either through the front panel or the HP IB the ERR annunciator on the front panel comes on and the ERR bit in the serial poll register is set The power supply does not execute the command and remains at previously set values Pushing the ERR button in local mode displays the error message and clears the error The error indicator may also indicate that an instrument failure has occurred Refer to Appendix D for further details CONNECTING THE LOAD Each terminal block cover on the rear panel is secured by a locking tab which snaps into a slot at the left of the terminal block To remove insert a screwdriver into this rectangular slot and move the locking tab to the left When the locking tab releases gently pull the termi
136. setting a value places the display in the supply metering mode ENTER Enters the values on the display for the specified function initiates the function and returns the display to the metering mode Pressing this key without setting a value will result in retention of the previous values and returning the display to the metering mode AA LINE Switch Turns ac power on and off Normal Self Test Indications If the supply passes the self test the display will first show all segments of the LCD display with annunciators on as illustrated in Figure 3 2 28 08 2908 08 888 08 8 28 88 YYY YV YV YYYY YV VK 1 2 3 4 CV CC UNR OCP ERR RMT ADDR SRO OUTPUT ENBLD Figure 3 2 Test Pattern of all Display Segments at Power on After all segments are displayed the supply s HP IB address will appear for approximately 2 seconds as shown in Figure 3 3 As shipped from the factory the power supply s address is set to 5 You must know this address before you can remotely program your supply see Reading the HP IB Address page 39 oO ico ee D vvvvvvvvvvv Y 1 2 3 4 CV CC UNR OCP ERR RMT ADDR SRG OUTPUT ENBLD Figure 3 3 Typical Address Display During Power On When self test is successfully completed the output voltage and current readings both approximately 0 for output 1 will appear in the display as shown in Figure 3 4 Note that the CV annunciator will also indicate that the output is in
137. sists of voltage overvoltage and current tests It is assumed that power has already been turned on the supply has passed the power on self test loads are not connected to any of the supply s outputs and sense clips are connected between the sense terminals and the output terminals NOTE The following procedures are identical for all models and for all outputs Use the OUTPUT SELECT key to select an output to be tested If an output fails any of the tests refer to the troubleshooting section in the Service Manual 36 Getting Started Voltage Test 1 Set the voltage of the selected output to 10 V by pressing vseT i Co ENTER 2 Check that the display reads approximately 10 V and 0 A and the CV annunciator is on indicating that the supply is in the constant voltage mode of operation Overvoltage Test 1 Program the overvoltage protection OVP to 19 V by pressing Lo SET 2 Set the voltage to 16 V by pressing 6 3 Check that the display reads approximately 16 V and 0 A 4 Set the voltage to 20 V by pressing Lo 5 Check that the display reads OVERVOLTAGE 6 Reset the supply by pressing 6 RST 7 Check that the display reads approximately 16 V and 0 A Current Test 1 Turn off the supply 2 Remove the barrier block cover from the output to be tested and connect a short circuit jumper wire between the V and V terminals of the output being tested 3 Turn on the supply UTPUT 4 Use t
138. standards IEC 348 UL 1244 and CSA 22 2 No 231 Dimensions all models Height 132 6 mm 5 22in Width 425 5 mm 16 75in Depth 497 8 mm 19 6in Weight all models Net Weight 17 4 kg 38 Ib Shipping Weight 22 7 kg 50 Ib 20 General Information USING 14 AWG 50 FOOT CABLE AND REMOTE SENSING USING 14 AWG 5 FOOT CABLE AND REMOTE SENSING USING 20 AWG 50 FOOT CABLE AND REMOTE SENSING USING 20 AWG 5 FOOT CABLE AND REMOTE SENSING USING LOCAL SENSING AND CAPACITIVE LOAD RIGHT AT OUTPUT TERMINALS 1111 ett iil STABLE OPERATING AREA ABOVE LINES POOT eee aes H YT 8 Z 5 g pa Hi E E g oO 5 E 3 SuF 1OuF 500uF 1000uF 5000uF 10 000uF 50 000uF 100 000uF CAPACITANCE NOTE CAPACITORS HAVING LOW CAPACITANCE AND LOW ESR E G CERAMIC AND FILM CAPACITORS ARE NOT RECOMMENDED FOR USE AS BYPASS CAPACITORS AT THE END OF A LONG LOAD CABLE SEE ILLUSTRATION BELOW THIS TYPE OF CAPACITOR MAY CAUSE THE OUTPUT TO BECOME UNSTABLE BECAUSE OF RESONANCE EFFECTS WITH THE LOAD LEAD INDUCTANCE MOST ALUMINUM AND TANTALUM CAPACITORS FALL WITHIN THE STABLE OPERATING AREA OF THE GRAPHS SHOWN ABOVE REFER TO PARAGRAPHS 4 6 THROUGH 4 14 FOR ADDITIONAL INFORMATION ABOUT C
139. supply output terminals when using local sensing However voltage transients may be produced at the load by noise induced in the leads or by load current transients acting on the inductance and resistance of the load lead If it is desirable to keep voltage transient levels to a minimum place an aluminum or a tantalum capacitor with an approximate value of 10 uF per foot 30 5cm of load lead right across the load see Figure 4 5 Refer to Figure 1 4 for capacitive load stability considerations Programming Response Time with an Output Capacitor Because voltage programming into an external output capacitor may cause the supply to briefly enter CC operating mode voltage programming response time may be longer than that specified in Table 1 1 Use the following formula to estimate the additional response time Additional Added Output Capacitor Change in Vout Response Current Limit Setting Time Open Sense Leads The sense leads are part of the supply s feedback path Connect them in such a way so that they do not inadvertently become open circuited The power supply includes protection resistors that reduce the effect of open sense leads during remote sensing operation If the sense leads open during operation the supply returns to the local sensing mode with the voltage at the output terminals approximately 2 5 higher low voltage outputs or approximately 3 higher high voltage outputs than the programmed value Output Connections
140. surement and control Units with this symbol are not completely circuits designed to be operated with disconnected from ac mains when this switch is one terminal at earth potential off To completely disconnect the unit from ac mains either disconnect the power cord or have a qualified electrician install an external switch Herstellerbescheinigung Diese Information steht im Zusammenhang mit den Anforderungen der Maschinenl minformationsverordnung vom 18 Januar 1991 Schalldruckpegel Lp lt 70 dB A Am Arbeitsplatz Normaler Betrieb Nach EN 27779 Typpr fung Manufacturer s Declaration This statement is provided to comply with the requirements of the German Sound Emission Directive from 18 January 1991 Sound Pressure Lp lt 70 dB A At Operator Position Normal Operation According to EN 27779 Type Test DECLARATION OF CONFORMITY according to ISO IEC Guide 22 and EN 45014 Manufacturer s Name Hewlett Packard Company Manufacturer s Address 150 Green Pond Road Rockaway New Jersey 07866 U S A declares that the Product Product Name a Multiple Output System Power Supply b Precision Multiple Output System Power Supply Model Number a HP 6621A 6622A 6623A 6624A 6627A b HP 6625A 6626A 6628A 6629A conforms to the following Product Specifications Safety IEC 348 1978 HD 401S1 1981 EMC CISPR 11 1990 EN 55011 1991 Group 1 Class B IEC 801 2 1991 EN 50082 1 1992 4 kV CD 8 kV
141. t then send the fault query FAULT 2 using output 2 as an example and address the supply to talk if you want to find out which of the conditions you unmasked in Figure 5 3 are true For example if the supply was in overvoltage and that condition was unmasked then the response from the fault query will be 8 see Table 5 5 NOTE When you query the fault the fault register is cleared Performing a serial poll will reset the PQS bit but will not clear the fault register If the SRQ on error was set then you can send the error query ERR and address the supply to talk The response will identify the error by its code see Table 5 8 76 Remote Operation Service Request Enable Disable You can query the status of the service request enable disable function by sending the query SRQ and addressing the power supply to talk The response from the supply is one of the following 0 1 2 or 3 0 indicates that the service request capability except for power on see The Power On Service Request information below is disabled 1 indicates that it is enabled for output fault conditions 2 indicates that it is enabled for error conditions 3 indicates that it is enabled for both fault and error conditions The ability to generate service requests can be enabled or disabled using the SRQ command as described below To disable the service request capability except for power on send SRQ 0 To enable the service request capability for all o
142. t ch gt The specified output board is down no output Error Codes and Messages 109 Error Code ERR query Message ERR key NO ERROR INVALID CHAR INVALID NUM INVALID STR SYNTAX ERROR NUMBER RANGE NO QUERY DISP LENGTH BUFFER FULL EEPROM ERROR HARDWARE ERR HDW ERR CH 1 HDW ERR CH 2 HDW ERR CH 3 HDW ERR CH 4 NO MODEL NUM CAL ERROR 110 Error Codes and Messages Table D 2 ERROR Responses Explanation Indicates there are no errors You sent the supply a character it did not recognize The format of your number is incorrect Check syntax see Chapter 5 You sent a command the supply does not understand Resend a recognizable command You sent a command with improper syntax Check syntax of your command see Chapter 5 An out of range number was sent Send a new number within the legal range The computer addressed the supply to talk but it did not first request data Send query first and then address the supply to talk Quoted string in the DSP command exceeds the display length of 12 characters May occur if too many numbers are sent Error code 4 or error code 5 are more likely to occur for this condition The EEPROM on the HP IB board is not responding correctly to programming commands An instrument failure has occurred and service is required Refer to the Troubleshooting Section in the Service Manual An output error has occurred on an unknown output Service is required
143. t was measured after the VHI command was sent The power supply uses these values to calculate the voltage and voltage readback correction constants of the specified output Continue to the next command 5 OVCAL lt channel gt This command automatically calibrates the programmable overvoltage This can only be done after the voltage has been calibrated It may take up to 10 seconds for this command to execute During this time the front panel display indicates CALIBRATING When the front panel display of the power supply no longer indicates CALIBRATING the overvoltage portion of the calibration procedure is complete The voltages on the output are returned to zero volts after the overvoltage calibration To continue with the current portion of the calibration procedure connect a four terminal 0 1Q current shunt resistor 0 05 10 A between the V and V output terminals Connect the voltmeter to the resistor s sense terminals Refer to the current calibration setup in Figure A 1 Continue calibrating output 1 with the following commands 6 IHI lt channel gt This command causes the current of the specified output channel to go to the high calibration point full scale After the command is sent use the voltmeter to read the voltage drop across the current shunt resistor Divide this reading by the shunt value to derive the actual current in amps lt Ihi gt put out by the supply Continue to the next command Ds ILO lt chan
144. the constant voltage mode Getting Started 35 VBA V DINA v 1 2 3 4 CV CC UNR OCP ERR RMT ADDR SRA OUTPUT ENBLD Figure 3 4 Typical Display at Power On Self Test Errors If the supply fails the power on self test all power supply outputs will remain disabled off and the display will indicate the type of failure and the output channel on which it occurred Figure 3 5 shows that self test detected an error in output channel 3 Error messages that could appear on the display if self test fails are listed below Self test error messages are explained in Appendix D and troubleshooting procedures are given in the Service Manual for the HP 6621A 6624A and 6627A Power Supplies You may also call your HP Sales office for help Power On Self Test Error Messages HDW ERR CH N 8291 FAILED TIMER FAILED CV DAC CH N CC DAC CH N OV DAC CH N FUSE CH N NOTE N specifies the failed output channel number 1 2 3 or 4 as applicable EOAR ERR ER 8 vvvvvvvvvvvy y 1 2 3 4 CV CC UNR OCP ERR RMT ADDR SRO OUTPUT ENBLD Figure 3 5 Sample Self Test Failure Display Checking Out Your Supply Using Local Control The following procedures use the display and keys on the front panel to check each of your power supply s outputs No test equipment other than a jumper wire 14 AWG is required to perform these tests The tests must be repeated for each output of your particular supply The checkout con
145. the error handling routine LINE 130 Disables interrupt capability while processing LINE 140 Brings in the common block for the I O pathname LINE 150 180 Conducts a serial poll If bit 0 in serial poll register indicates a fault for output 1 output 1 is disabled and the overvoltage circuit is reset LINE 190 220 Checks bit 1 in serial poll register for a fault on output 2 If true output 2 is disabled and the overvoltage circuit is reset LINE 230 Reads fault registers to clear FAU bits in serial poll register 100 Programming with a Series 200 300 Computer Error Detection The power supply can recognize programming errors and can inform you when a programming error occurs When an error is detected no attempt is made to execute the command Instead a bit in the serial poll register is set If SRQ2 or SRQ3 is set an interrupt will be generated The following program checks for programming errors and can be entered and run as is While it is running commands can be sent to the power supply from the keyboard If the ERROR annunciator on the power supply s front panel indicates that an error has been detected depress the labeled softkey to display the error on your computer screen 10 ASSIGN Ps TO 705 20 COM Ps Ps 30 ON KEY 0 LABEL ERROR CALL Err_trap 40 Lbl GOTO Lbl 50 END 60 70 80 SUB Err _ trap 90 OFF KEY 100 COM Ps Ps 110 OUTPUT Ps ERR 120 ENTER Ps Err 130 OUTPUT 2 USING K CHR
146. tial values Table 5 3 lists the parameters and their initial values Table 5 3 Initial Conditions Parameter Initial Value Voltage Current Reprogramming Delay Store Recall Registers Overvoltage OV Output Channels OCP Enabled UNMASK Register SRQ Front Panel Metering Power Supply Address Local Control PON Bit PON SRQ Cal Mode Power Supply Commands 0 Minimum current limit 20 mS 0 volts and min current limit 23 V on low voltage outputs and 55 V on high voltage outputs On 0 cleared 0 Off Output 1 Last stored value Factory set to 5 On enabled On Last stored value Factory set to 0 Off This section discusses the commands which you will use to program the supply s voltage and current protection circuits and enhanced features like storage and recall registers and reprogramming delay When programming you should be aware that the current voltage and overvoltage ranges for each output of your supply may differ Table 5 4 shows these values for the power supply If you send values out of these ranges you will get a number range error A summary of all commands appears in Appendix C The output voltage of some output channels exceeds the safe operating limit of 42 2 V To avoid any electrical shock program the voltage to zero volts or turn off ac input power before changing any rear panel connections Make certain all straps are properly connected terminal block screws are securely ti
147. tion 220 V Option 240 V Option High Line Inrush Current 85 A 85A SOA 50 A pk High Line Input Current 6 3 A 57A 3 0 A rms Fuse Rating 8A 8A 4A HP IB Interface Capabilities SH1 AHI T6 L4 SRI RL1 PP1 DC1 DTO CO El Current Sink Capability Current sink limits are fixed approximately 10 higher than the maximum current source limits for a given operating voltage at any voltage above 2 5 V see Chapter 4 Command Processing Time see Figure 1 3 7 milliseconds typical with front panel display disabled Using STO and RCL commands allows you to change all the voltage and current settings in about 10 mS with front panel display disabled Series and Parallel Operation Two outputs can be operated directly in parallel or can be connected for straight series operation Refer to Chapter 4 for more information Reactive Load Capability All outputs have been designed with the ability to operate with significant reactive loads without instability refer to Figures 1 4 through 1 6 General Information 19 Table 1 3 Supplemental Characteristics continued Output Impedance Approximated by a resistance in parallel with an inductance see graphs in Figure 1 7 The values for each output are 40 W Low Voltage 40 W High Voltage 80 W Low Voltage 80 W High Voltage 0 150 2 04H 0 3 Q 5 WH 0 15 Q 0 8 WH 0 5 Q 3 WH Safety Agency Compliance This series of power supplies is designed to comply with the following
148. ts when the field is reduced to 2 volts meter When subjected to radiate field strengths of 3 volts meter in the vicinity of 200 MHz the full scale readback accuracy of channel 1 increases from 23 millivolts at 5 volts output to 100 millivolts The accuracy reverts to the published value of 30 millivolts when the external field is reduced to 2 volts meter 6623A When subjected to radiated field strengths of 3 volts meter in the vicinity of 160 MHz the full scale programming accuracy of channel increases from 31 millivolts at 20 volts output to 50 millivolts The accuracy reverts to the published value of 31 millivolts when the field is reduced to 2 5 volts meter When subjected to radiate field strengths of 3 volts meter in the vicinity of 160 MHz the full scale readback accuracy of channel 1 increases from 30 millivolts at 5 volts output to 50 millivolts The accuracy reverts to the published value of 30 millivolts when the external field is reduced to 2 5 volts meter Addendum HP Sales and Support Office For more information call your local HP Sales Office listed in the telephone directory white pages Ask for the Electronic Instruments Department Or contact United States Europe Hewlett Packard Company European Headquarters 4 Choke Cherry Road Hewlett Packard S A Rockville MD 20850 150 Route du Nant d Avril 301 6704300 1217 Meyrin 2 Hewlett Packard Company 5201 Tollview Drive Rolling Meadows IL 60
149. ts with the OUT command as shown below For example to disable output channel send the following OUT 1 0 To enable output channel send the following command OUT 1 1 You can find out the present state of output 1 by sending the query OUT 1 and addressing the supply to talk The response from the supply is either a 0 to indicate output 1 is off or a 1 to indicate that the output is on When disabled the output behaves as if it were programmed to zero volts and minimum current Overvoltage OV Protection The programmable OV is a protection feature which can be set by the operator to protect the load against excessive voltage When the actual voltage exceeds the programmed overvoltage setting for a given output channel the OV is tripped The OV circuit will fire the SCR crowbar which shorts across the output and the output assumes a low impedance state For example to program the OV of output channel 1 to 9 5 V send the following command OVSET 1 9 5 To find out the OV setting for output channel 1 send the following query and address the supply to talk OVSET 1 Remote Operation 71 To enable an output after it went into overvoltage you must first remove the overvoltage condition and then send the OV reset command To reset output 1 send OVRST 1 If you send the reset command without first removing the OV condition the supply will fire the OV again NOTE If the programmable OV fails the supply has a fixed OV circuit whic
150. turn on send DCPON 2 To disable all outputs in constant current mode at turn on send DCPON 3 Table 5 8 Error Messages Front Panel HP IB Explanation Response Code NO ERROR This is the response to the ERR query when there are no errors INVALID CHAR You sent the supply a character it did not recognize INVALID NUM Format of your number is incorrect Check number syntax INVALID STR Occurs when you send a command the supply does not understand SYNTAX ERROR Either too many parameters are sent without delimiters or the number representation is incorrect Follow the Syntax Diagram in Figure 5 2 Check spaces and delimiters NUMBER RANGE An out of range number was sent Send a new number within the legal range NO QUERY Computer addressed the supply to talk but it did not first request data Send query first then address supply to talk DISP LENGTH Quoted string exceeds the display length of 12 characters Shorten string to a maximum of 12 characters BUFFER FULL This error may occur if too many numbers are sent Error 4 or 5 may occur first EEPROM ERROR EEPROM is not responding correctly to programming commands An instrument failure has occurred and service is required 80 Remote Operation HARDWARE ERR An output error has occurred in an unknown output Service is required HDW ERR CH 1 Errors 11 through 14 refer to a specific output where there is an output error Service is required HDW ERR CH 2 Same as in Error
151. turn to the voltage and current settings determined by the present VSET and ISET values Overvoltage Setting You can send an overvoltage setting value to the power supply directly in volts If the output voltage exceeds this setting the output crowbar is fired and the output voltage is quickly downprogrammed and disabled 0 volts output To set the overvoltage value of output 2 to 3 5 volts send OUTPUT 705 OVSET 2 3 5 Getting Started 41 Overcurrent Protection The output will go to the off state 0 volts and min current when the overcurrent protection OCP feature is enabled and the output is in the CC mode To enable the overcurrent protection mode for output 2 send OUTPUT 705 OCP 2 1 To disable the overcurrent protection mode for output 2 send OUTPUT 705 OCP 2 0 When overcurrent protection is disabled and the output is in CC mode the output current will be limited to and will stay at the ISET value Returning the Supply to Local Mode In the remote mode RMT annunciator on the front panel keys have no effect on any of the supply s outputs and only the computer can control the supply However you can still use the front panel display to monitor the output voltage and current or check any of the present settings VSET ISET OVSET etc of the selected output channel If you want to use the front panel keys to change the output settings you must return the supply to the local mode You can return the sup
152. ut adequate cabinet ground connection AS 8120 1348 812 1351 1251 3498 STANDARD PLUG ONLY E ES Es 8120 1368 8128 1689 8128 2104 Figure 2 4 Power Cord Plug Configurations SHOCK HAZARD Connect the power cord to a grounded receptacle before you connect any external floating voltages to the supply The offset pin on the standard three prong power cord connector is the ground connection If a two contact receptacle is encountered it must be replaced with a properly grounded three contact receptacle in accordance with the National Electrical Code local codes and ordinances The work should be done by a qualified electrician Line Voltage Conversion You can change the supply to accept 100 V 120 V 220 V and 240 V ac input by adjusting the voltage selector card located inside of the line module see Figure 2 3 After you have changed the line voltage refer to Table 2 2 and check that the fuse inside the line module is the correct fuse for that line voltage The procedure is as follows 1 Turn off power and remove the power cord from the ac input socket on the back of the power supply 2 To open the line module move the plastic door on the module aside If your line voltage change requires a change in the rating of the fuse rotate FUSE PULL to the left and remove the fuse 3 Grasp the voltage select pc board with a pair of needle nose pliers and slide it out of its slot 4 To select a voltage orient the pc board so that the
153. ut board employs series regulation techniques A regulator element is connected in series with the load and operates in the linear region between saturation and cutoff of the transistor characteristic curve Regulation is achieved by varying the conduction of the series element in response to a change in line voltage or circuit load The output board receives digital signals from the HP IB board and converts them to analog signals which program the output voltage current and overvoltage values The output may be programmed remotely over the HP IB using commands see Chapter 5 or locally from the supply s front panel using the control keys see Chapter 6 The output board can be commanded to send measurement and status data back over the HP IB and or front panel The data is sent back via the supply s HP IB board HP IB readback capabilities include output voltage and current present and accumulated status and all programmed settings The front panel LCD display can indicate the output voltage and current the supply s HP IB address error messages and programmed values Annunciators on the front panel indicate the operating status of the selected channel output board ARE MULTIPLE OUTPUT SYSTEM POWER SUPPLY ONTROL STATUS CONTROL STATUS COMPUTER HP TB OUTPUT BOARD NO 2 CONTROL STATUS OUTPUT CONTROL STATUS CONTROL STATUS NOT USED IN ALL MODELS Figure 1 2 HP 6621A 66
154. utput 2 s voltage to a higher value than the voltage of output 1 One way to accomplish this is to first program output 2 to the maximum allowable voltage setting for the desired operating range see Table 4 2 or Figure 4 2 These values are 1 higher than the rated voltage for the operating range Then program output 1 s voltage to the desired operating voltage The lower voltage setting of output 1 will determine the voltage that appears across the load The current limit point of the paralleled outputs is the sum of both individual current limit points The output current of the parallel combination is the algebraic sum of the individual current readbacks The OV and OV terminals of output 1 should be wired to the OV and OV terminals of output 2 When programming the overvoltage setpoint set both outputs to the same overvoltage value When resetting the overvoltage first disable both outputs by using the OUTPUT ON OFF key or OUT command Next reset both overvoltages Finally re enable the outputs with the OUTPUT ON OFF key or OUT command Table 4 2 Maximum Allowable Voltage Setting Output Type 40 W 8 80 W Maximum Low Range Voltage Maximum High Range Voltage Low Voltage Output 7 07 V 20 2 V High Voltage Output 20 2 V 50 5 V NOTE Below 2 5 V the downprogrammer cannot sink the maximum rated current See Figures 4 2 and 4 3 To operate parallel outputs at voltages under 2 5 V program both outputs to the same voltage setting Depen
155. utput faults SRQ 1 To enable the service request capability for errors send SRQ 2 To enable the service request capability for both faults and errors send SRQ 3 The Power On Service Request You can also cause the power supply to request service every time it is switched on or every time there is a temporary loss in power To do this send the following command PON 1 If you want to disable this facility send the command PON 0 If you want to find out if the power on SRQ is enabled or disabled send the following query PON and address the supply to talk The supply will respond with a 1 or 0 as discussed above NOTE The power on PON SRQ mode is stored in the non volatile memory of the supply so that although the supply may be switched off it will remember the status of the last PON command at power on and respond accordingly Remote Operation 77 Table 5 7 summarizes all the conditions under which a service request will be generated Table 5 7 Condition for Generating a Service Request Condition State of PON SRQ RQSBit Any 0 Power on Error Fault Reprogramming Delay The power supply may switch modes or become unregulated momentarily after a new output value is programmed Because of their short duration these cases may not ordinarily be considered a fault but the supply will recognize this deviation and generate a fault signal To prevent this the reprogramming delay feature is implemented Reprogram
156. values are stored for one output channel at a time A separate calibration command calculates and stores correction constants for the internal overvoltage circuit This appendix lists the equipment that you need shows the test setup to perform the calibration gives a general calibration procedure that explains all of the calibration commands and gives a sample program you can use if you have a HP 3456A voltmeter and a HP Series 200 300 computer with BASIC Security against accidental calibration is available A jumper inside the unit may be moved to disable all calibration commands Access to this jumper requires opening the unit see the Service Manual Tables A 1 and A 2 give the data ranges for all of the power supply calibration commands Refer to Figure 5 2 for the syntax structure of the calibration commands You can either execute the calibration commands directly from the keyboard or you can use them in a program to reduce the time involved in calibrating each output NOTE The memory used to store correction constants will accept and store data about 10 000 times which is more than sufficient for normal calibrations over the life of the instrument However do not put the unit in a calibration loop that repeatedly turns the calibration mode on and off Test Equipment and Setup Required The following test equipment is required for calibration 1 A computer connected to the HP IB connector on the back of the power supply 2 A voltmet
157. vice and its address is between O and 7 Addresses O through 7 define which data line 1 through 8 the supply will respond on If the address is set to 8 or greater the supply will not respond unless remotely configured The power supply may be remotely configured to respond with a 0 or 1 on any of the data lines to indicate that it is requesting service This is done in accordance with IEEE 488 1978 Serial Poll In a serial poll the controller polls each instrument on the bus one at time The power supply responds by placing the contents of the eight bit serial poll register on the HP IB data lines Page 75 discusses the Serial Poll Register and defines the function of each of the bits After the serial poll the service request is cleared and the SRQ annunciator at the front panel is reset off However the condition that generated the service request may still be present See page 76 Device Clear The Device Clear command is typically used in systems to send all devices in the system to a known state with a single command It may be implemented as an addressed or an unaddressed command The power supply CLR command performs the same function as Device Clear see page 73 HP IB Address Selection You can find out the present address or change the address of the supply by using the front panel ADDR key as described in Chapter 3 Any address 0 through 30 is a valid address If you program an address outside this range you will get a number ran
158. xecuted locally from the supply s front panel as indicated in the table Command headers are accepted in upper or in lower case letters although only upper case letters are used in this summary The brackets lt gt indicate a number to be sent Note that lt ch gt must specify an output channel number from 1 through 4 as applicable Commas or spaces are required between numbers Spaces are optional between the command header and the first number No commas are allowed between header and first number Use semi colons between multiple commands sent in one statement Chapter 5 gives a complete description including syntax of most of the commands listed Calibration commands are described in Appendix A Two of the commands listed ROM and VMUX are described in the Service Manual Table C 1 Command Summary ASTS lt ch gt Queries the accumulated status ASTS of the specified output channel The response integer 0 255 represents the sum of the binary weights of the ASTS register bits see page 74 The ASTS register is automatically set to the present status after being queried Returns the entire power supply all outputs to the power on state except that the supply is not unaddressed and its store recall registers are not changed see Clear Command page 73 CMODE lt on off gt Turns the calibration mode on or off On off is a 1 to turn the calibration mode on a 0 turns it off see Appendix A Queries if the calibration mode is
159. y of the bit positions indicates that the condition is true As long as the condition continues to be true the bit will remain set Assignments for the bits are shown in Table 5 5 Decoding of the reading is based on the weighted number placed on each bit of the 8 bit status registers For example bit position 5 in the register has a bit weight of 32 see Table 5 5 Each bit is assigned to a particular condition and the corresponding bit weight is used to identify that condition When set bit 5 indicates that the associated output is in the unregulated state If this is the only bit that is set the number 32 will be returned when the output s status register is queried Table 5 5 Bit Alignment for the Status A Status Fault and Mask Register Bit Position Bit Weight Meaning Where CV Constant Voltage Mode CC Positive Constant Current Mode CC Negative Current Limit Mode OV Overvoltage Protection circuit tripped OT Over Temperature Protection circuit tripped UNR Unregulated Mode OC Over Current Protection tripped CP Coupled parameter See Note Note When the range is automatically switched as discussed on page70 the CP bit is set It is cleared when you send a voltage or current value that causes no range change To query an output channel for its status you must specify the output channel For example to find out the status at output 2 send the following query and address the supply to talk STS 2 A

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