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Manual - IET Labs, Inc.

1. O IEEE 488 INTERFACE e r aS C 2 C 2 BATTERY 2 C 2 PORT C mie 2 xt of gt C D I 2 PARALLEL PORT RS 232 INTERFACE 90 250 V 2 C 2 ui 47 63 Hz 2 PN 40 WATTS Figure 1 4 1865 Instrument Fuse Drawer 1 Open the fuse drawer by inserting a small flat head screwdriver behind the small tab to pull the drawer outward If you wish to remove the drawer from the ac inlet module not required in order to change the fuse press the sides inward at the rear of the drawer and pull the drawer out 2 Remove the fuse from the drawer by prying upward using a small flat head screwdriver 3 Insert the replacement fuse 4 Optional Insert a spare fuse in the front section of the drawer 5 Slide the tray back into the into the instrument ac inlet module Page 18 Introduction 1 4 4 Safety Inspection A Before operating the instrument inspect the ac power inlet module on the rear of the 1865 instrument to ensure that the properly rated fuse is in place otherwise damage to unit is possible Refer to paragraph 1 4 3 The 1865 instrument is shipped with a standard U S power cord with Belden SPH 386 socket or equivalent and 3 wire plug con
2. 36 Page iii Contents Continued Operation Section 2 Continued 20 RM 37 2 09 IDISMIAY Lype ns aaa eee 37 2 0 3 2 RESU FOIE 38 39 WEEE AAS S 2 40 40 2 6 3 6 Saving Measurement Results USB 40 2 04 E MOI nte cadets 42 2 04 1 Save SCID fatuus 43 2502422 Recall Sel ates uu 45 PAD UAM e 46 DOAA LO E OU ai muhu huuu Qua 47 PX UE E CANOE d a ka u ankaqa a 47 2 046 eL Tite AUG u 48 de BIADSSQ uu rines asino ua ete EE 49 ROAS Calibradon Dole DOT u MON tecta Des 49 ZOTI at td ee 50 2 0 4 10 LD n Dukh 50 2 4 Input Output Ditet LAC ese oct D o ooo m Vati aC e ud 50 2b LO T i 002 xuat 50 2250 JIBEBR 488 2 MENICE y u u ede on uU 52 2 7 3 Sample Program for National Instruments GPIB Card 27 2 7 4 Sample Program for IO Tech GPIB 58 2 1495 189292 Hte la CS ouai i sive wast 59 2 1 0 Sample Program Tor 52322 exo ete WR a AG 60 2s Pintu aco reta DM em Qa a prd 61 2 8 Error Messa eoo uu ovii tanium a 62 Applications
3. 0 0005 FS 2 pA IpA to 100 10 0 0005 FS 2 pA 5 5 Pass Fail 1 limit LCD graphic display Voltage warning indicator Pass Fail indicator specified at front panel connectors Page 1 Test Cycle I O Interface Input Terminals Dimensions Weight Environmental Power General Accessories Supplied Accessories Available Page 2 Specifications Continued Manual Automatic Charge Measure Discharge Charge time 0 300 sec Dwell time 0 300 sec Measure time 0 999 sec Discharge time 0 300 sec Standard RS232 Port w safety interlock Optional 1865 01 IEEE 488 2 factory installed at unit purchase 1865 02 USB connection 1865 03 Rear panel input terminals factory installed at purchase 1865 70 IEEE 488 2 field retrofit Four sheathed banana plugs front or rear mount optional unknown red unknown black guard blue ground green Bench with tilt back bail 133 4mm high x 444 5mm wide x 406 4mm deep Approximately 8 2 kg Net Approximately 11 8 kg Shipping MIL T 28800D 3 Class 5 Style E F Operating 0 C to 50 C stated accuracy lt 45 RH Storage 40 C to 71 C Altitude lt 2000m Installation Category 1 Pollution Degree 1 90 250V 47 63 40 W max e Fully programmable via menu e Zeroing e Stored test conditions and results e Selected measurement units engineering or scienti
4. p Ry x AJ t Q cm where A x D1 g y 4 DI diameter of inner electrode D2 diameter of outer electrode g 15 the distance between inner amp outer electrode Note g can be factored out only if the thickness of the sample is much smaller than g 1 t lt lt g 8mm 8mm is the maximum thickness of the QuadTech Resistivity Cell EN GUARD Electrode Figure 6 4 Volume Resistance 6 1 5 Cleaning the Resistivity Test Fixture Page 84 Optional Accessories Before touching any of the electrodes disconnect all wires from the measuring device Clean the remote test fixture only if the previously tested material left some type of remnant or residue on any of the electrodes Do not remove the rubber conductor unless it comes out by itself where it would then need to be cleaned and replaced as 15 For removal of dirt and wax use warm clean water first with a lint free cloth 1f residue 15 still visible use mild detergent diluted in water to wipe down residue If all else fails use isopropyl alcohol on a Q tip to soften and remove dirt from selected areas on electrodes Do not douse the electrodes with 1sopropyl alcohol use only a small amount on a Q tip Dry thoroughly with a lint free cloth before using Optional Accessories Page 85
5. Applications Page 69 3 6 Guarded 3 Terminal Measurements In many cases it is necessary to measure the resistance between two points in the presence of resistance from each of these points to a third point This third point can often be guarded to avoid error caused by the extraneous resistance This can best be illustrated as shown in Figure 3 2 below Here Rx 1 the quantity to be measured in the presence of RA and Rp If the junction of RA and 15 tied to guard RA 1 placed across the voltage source and has no effect if it is greater than 1 25 As long as is greater than Rg standard range resistor the error caused by Rp is minimized thus if there 1s a choice its better to have the higher of the two stray resistances connected to Rp GUARD Figure 3 2 Guarded Measurement Configuration The guard terminal can be used whether GUARD or the UNKNOWN terminal 15 grounded but it S important to note that 1f the UNKNOWN terminal 1s grounded the GUARD terminal will be at a high negative voltage level When the GUARD terminal 1 connected to a true ground of a device such as chassis it 1s the one that must be grounded not tUNKNOWN Page 70 Applications Section 4 Theory 4 1 General The 1865 Megohmmeter IR Tester consists of a standard mechanical package LCD display keypad microprocessor unit digital I O interface and power supply It incorporates circuitry unique to the 1865 an
6. DOr on Pass 0 TL c2 Figure 2 9 Setup Menu The first of the three main menus 15 Setup shown in Figure 2 9 Each function controls a measurement condition and is described detail below 2 6 2 1 Voltage I O Utilities Voltage Charge Time Dwell Time Measure Time Discharge Time Mannal Limit OD on Pass Figure 2 10 Test Voltage Entry Accepts entry of a test voltage up to 6 digits and decimal between 1 and 1000 V This is the voltage applied to the unit under test during the test cycle and present at the DUT connection anytime that the CAUTION HIGH VOLTAGE lamp 1s ON As in the case of many of the menu entries on the 1865 instrument an error message will be displayed for an invalid entry Operation Page 29 2 6 2 2 Charge Time Utilities Voltage Charge Time Dwell Time 10 Measure Time 10 Discharge Time 10 Mode Auto Manual Range Limit Stop on Pass to Average Figure 2 11 Charge Time Entry Accepts entry of a charge time between 0 and 300 seconds 1 second intervals up to 3 digits If the selection 1 out of range an error message will be displayed This marks the time when the test voltage 15 first applied and the unit under test is allowed to charge up to this voltage Even if the charge time 15 entered as zero there 15 still a small delay during the charge phase In this case or even with much longer charge times th
7. PRECISION INSTRUMENTS FOR TEST AND MEASUREMENT 1865 Megaohmmeter IR Tester User and Service Manual Copyright 2014 IET Labs Inc Visit www ietlabs com for manual revision updates 1865 im Sept 2014 JET LABS INC TEL 516 334 5959 FAX 516 334 5988 PRECISION INSTRUMENTS FOR TEST AND MEASUREMENT ee IET ET LABS INC w TEL 516 334 5959 FAX 516 334 5988 WARRANTY We warrant that this product 15 free from defects in material and workmanship and when properly used will perform in accordance with applicable IET specifications If within one year after original shipment it is found not to meet this standard it will be repaired or at the option of IET replaced at no charge when returned to IET Changes in this product not approved by IET or application of voltages or currents greater than those allowed by the specifications shall void this warranty IET shall not be liable for any indirect special or consequential damages even if notice has been given to the possibility of such damages THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES EXPRESSED OR IMPLIED INCLUDING BUT NOT LIMITED TO ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE AN WARNING AN OBSERVE ALL SAFETY RULES WHEN WORKING WITH HIGH VOLTAGES OR LINE VOLTAGES Dangerous voltages may be present inside this instrument Do not open the case Refer servicing to qua
8. When replacing old appliances with new one the retailer 1s legally obligated to take back your old appliances for disposal Page 6 Condensed Operating Instructions WARNING High voltage is applied to the measurement terminals of the 1865 any time the CAUTION HIGH VOLTAGE LED is ON While the current from the instrument is limited the energy stored in a capacitive device connected to the terminals may be lethal Always make sure the high voltage indicator is OFF when connecting or disconnecting the unknown A flashing CAUTION HIGH VOLTAGE light and or DANGER on the display indicates a defective unit with dangerously high voltages possible at the input terminals Power the unit down and do not use General Information The 1865 Megohmmeter IR Tester is a computer controlled measuring instrument for direct readout of resistance and current The voltage applied to the device under test DUT is programmable from 1 to 1000 V A pass fail indicator provides a visual display of test results based on a preset limit A set of power up default test conditions are stored in the unit and are as set by the factory 1V test times zero until reprogrammed by the user Start up The 1865 can be operated from a power source between 90 V and 250 Vac at a power line frequency of 47 to 63 Hz The standard 1865 15 shipped from the factory with a 2 5 A fuse in place for 115 V or 220 V operation To change the fuse refer to paragraph 1 4 3 Connect
9. Electrode Guard Function Electrode lt Switch Top Electrode FUNCTION Sample REST Ring Bottom Electrode Ring Rv 9 Push Button LOEK Open Close Fixture Figure 3 1 1865 11 Surface Plate Test Sample Cell Page 66 Applications The 1865 11 Test Cell measures resistance and with unique formulas the resistance can be converted to surface and volume resistivity The formulas required to convert from measured resistance to resistivity are given in the ASTM D257 Standard For the circular or concentric electrode configuration the resistivity 1s calculated by Surface P Volume A Resistivity Ps 9 P Resistivity P 5 t Ry P effective perimeter of measuring electrode A effective area of measuring electrode g dimension of space between electrodes 2 and 1 t average thickness of the specimen measured surface resistance in ohms R measured volume resistance in ohms Refer to ASTM D257 for formulas based on electrode configuration of the test cell 3 3 Capacitor Insulation Resistance 3 3 1 General The insulation resistance measurements of capacitors 15 different from that of resistors by the fact that some consideration must be given to the charge and discharge currents Consideration should also be given to high value low leakage capacitive devices relative to dc resistance measurements Inherent to some degree in all high resistance measurement instrumentation 15 the inability to provide stable leaka
10. MENU key to select menu display Press Right or Left Arrow key to select Setup Menu Press Up or Down Arrow key to select desired time charge dwell measure or discharge Press ENTER key to activate the corresponding time entry field Enter the desired time between 0 and 300 seconds measure 0 999 on later units Press ENTER key to finalize the time entry 2 Continue to set the other times as desired by repeating step 1 Page 10 Condensed Operating Instructions Setting Pass Fail Limit 1 To enter a single measurement limit for resistance or current depending on results display selected Press MENU key to select menu display Press Right or Left Arrow to select Setup menu Press Up or Down Arrow key to select Limit in sub menu Press ENTER key to activate the limit entry field Enter the numerical value up to 4 digits plus decimal point of the limit desired then enter the exponential value after first pressing the e select key use minus exponential value for current Press ENTER key to finalize the limit entry Changing Display Type and Units 1 To change displayed measurement results between Resistance Current or Pass Fail Press MENU key to select menu display Press Right or Left Arrow key to select I O Menu Press Up or Down Arrow key to select Display Press ENTER key to activate the selection field Press Up or Down Arrow key to select desired measurement results Resistance Current or Pass Fail
11. Section 3 3 1 Insulation Resistance LCS Hie Goma 65 3 2 Test Sample Resistivity Measurements 66 3 3 Capacitor Insulation Resistance 4 5 ob aa a 67 67 053 2 Dime k anan ak Ne pne aa uQ 68 Zar Discharge oca coa 68 3 4 Resistance put ER 69 3 5 Measurement of VoltaPe Coellicir DLE unu Ue eb RR ue 69 3 6 Guarded 3 Terminal Measurements 70 Page iv Contents Continued Theory Section 4 4 1 4 2 I Tel 2 uz u yas TIS CUMS MU DSS CIP IO a uy unun a 4 2 Basic Instrument Architecture 4 2 2 1865 Instrument Modules 4 2 5 cmsirument Opus euis un esce Roses Maintenance Calibration Section 5 5 1 252 RogutmeNildintendieeu uu ter Sd Battery Replacement uu ant 3 12 Resottine or bini and Date det HER ARTI E Selva 3BossoLDisSplay rete Sa Preventive Maintenance esos edo erano Mad au m r
12. analog instrument module and a power supply In addition there 15 an IEEE 488 2 option discussed briefly below 4 2 Instrument Description 4 2 1 Basic Instrument Architecture Processor Board The processor board provides the basic control for the 1865 It has a Pentium 4 processor mimics the IBM PC architecture and uses a DOS operating system Besides the central processing unit and memory modules it includes ports for a keypad a USB connection and an RS232 interface It stores instrument software an electronic chip disk The RS232 port is connected to its rear panel connector by a cable The processor board is stacked on the Digital Board which is mounted on the Analog Instrument board The processor board can have an optional IEEE 488 2 board stacked on it Digital I O Board The digital I O board provides interfaces to the LCD display the keypad and provides handler interface functions through a cable to the rear panel connection It also contains the circuitry for the instrument s many timing functions as well as a non volatile memory used for storing test setup conditions and corrections for instrument zeroing A battery backup for the RAM on this board is provided by 3 AA alkaline batteries which should be changed once a year This board is mounted on the analog instrument board the instruments main compartment The 3 batteries are installed in the long round tube towards the rear left of the unit Theory Page
13. current through this circuit should be between 1 and 5 mA nominal 10 mA max pin 34 start 620 ohms NN pin 35 Figure 2 33 Isolated Connection 2 7 2 RS 232 Command Set Refer to Table 2 4 below for a full tabulation of connections and Table 2 5 for the command set Page 52 Operation Table 2 5 IEEE and RS 232 Commands Command Function Parameter s CONFigure VALid Is filename valid to save XXXXXXXX SAVe DUPLicate Save setup as duplicate filename In battery backed up RAM XXXXXXXX NEW save setup as new filename in battery backed up RAM XXXXXXXX RECall filename Recall setup filename from battery XXXXXXXX backed up RAM FVALId Is filename valid to save XXXXXXXX FSAVe DUPLicate Save setup as duplicate filename on USB xxxxxxxx NEW Save setup as new filename on USB XXXXXXXX FRECall filename Recall setup filename from USB flash drive xxxxxxxx HANDler state Turn handler port OFF or ON 0 OFF 1 ON VOLTage value Set the voltage to value 0000 000 TCHarge value Set the charge time to value 000 TDWell value Set the dwell time to value 000 TMEasure value Set the measure time to value 000 TDIScharge value Set the discharge time to value 000 MODE Set the mode to A Auto M Manual CAUTION When using Manual MODE via the RS232 interface a delay time must be inserted between the issuing of the Start command and the sending of the Fetch command This delay time must be sufficient to ensure that the 1865 has displayed a meas
14. if a limit is to be used Press ENTER key to finalize the entry 2 To change the measurement results format between Scientific or Engineering units Press MENU key to select menu display Press Right or Left Arrow key to select I O Menu Press Up or Down Arrow key to select Result Format Press ENTER key to activate the selection field Press Right or Left Arrow to select desired results format Sci for Scientific or Eng for Engineering Press ENTER key to finalize the entry Page 11 Page 12 Section 1 Introduction WARNING High voltage is applied to the measurement terminals of the 1865 anytime the CAUTION HIGH VOLTAGE LED is ON While the current from the instrument is limited to a value that is not dangerous under most conditions the energy stored in capacitor connected to the terminals may be lethal Always make sure the CAUTION HIGH VOLTAGE LED 1 OFF when connecting or disconnecting the unknown 11 Unpacking and Inspection Inspect the shipping carton before opening If the carton 15 damaged contact the carrier agent immediately Inspect the 1865 instrument for any damage If the instrument appears damaged or fails to meet specifications notify IET refer to instruction manual front cover Retain the shipping carton and packing materials for future use such as returning for recalibration or service 1 2 Product Overview The 1865 Megohmmeter IR Tester 15 a general purpose high voltage instrument for r
15. mode from 1 mA to 1 pA The unit 1s available with front or rear panel input connections with guard and ground terminals to permit measurements of grounded or ungrounded devices Introduction Page 13 1 3 Controls and Indicators 1 31 Front Panel Controls and Indicators Figure 1 1 shows the controls and indicators on the front of the 1865 unit Table 1 1 identifies them with description and function 13 12 11 10 1865 DISPLAY SELECT Megohmmeter IR Tester RESISTANCE WARNING EL e 1 2 3 4 5 67 8 9 Figure 1 1 Front Panel Controls amp Indicators Table 1 1 Front Panel Controls and Indicators Reference Name Type Function Number Figure 1 1 1 HputPanel Connection for device Connection for device under test Banana Plug Terminal or Guard Input to Chassis GND r ee Banana Plug DUT Banana Plug GUARD Blue Sheathed Guard Terminal for 3 Lead Guarded Banana Plug Measurements Display LCD Graphic Displays measurement results instrument status and user interface menus 3 SELECT 4 Gray Push Buttons Function as indicated on adjacent display From top to bottom functions as Up 7 Down 4 Right or lt during Menu Selection Other functions include measurement units exponent Yes or No and del delete 4 Keypad White Push Buttons 12 keys for making numerical entries 0 9 decimal poi
16. of the range 2 standard 20 10 The value of the range 3 standard 200 11 The value of the range 4 standard 2 12 The value of the range 5 standard 20 13 The value of the range 6 standard 200 l4 The value of the range 7 standard 2 15 The open circuit correction for range 1 16 The open circuit correction for range 2 17 The open circuit correction for range 3 18 The open circuit correction for range 4 19 The open circuit correction for range 5 20 The open circuit correction for range 6 21 The open circuit correction for range 7 Command Function Parameters RST Reset This command performs a device reset CLS Clear Status This command clears status data structures ESR Event Status Register Sends the event status register information This 15 a destructive read STB Status Byte Register Sends user the status byte register information ESE Event Status Enable Register Sends the user event status enable register info SRE Service Request Enable Register Sends the user service request enable register info ESE Event Status Enable Register Writes the event status enable register info value SRE Service Request Enable Register Writes the service request enable register info value Status Byte Register Event Status Register Value CEEE i 7 128 Noe SRQSPOLReet None J 9 5 Simmer Standard Event Command Error Syntax Status Register
17. operation Selections Include Address through 16 Mode Talk or Talk Listen State Disable or Enable The instrument will function as either a Talk or a Talk Listen device in a system depending on the choice made by the operator under Mode Talk 15 generally suited to a simple system with no controller or other talkers for example a printer Talk Listen denotes full programmability and is suited for use in a system that has a controller or computer to manage data flow The handshake routine assures that the active talker proceeds slowly enough for the slowest listener 2 6 3 5 Handler Allows user to turn Handler Interface function ON or OFF When off Is selected input and output lines on the rear panel I O interface connector are ignored 2 6 3 6 Saving Measurement Results via USB Host Port The user can store measurement results on a USB flash drive When selected 1f a results file 1s not open the user 1s prompted for the filename up to 8 characters and the file 15 opened To close a results file that is currently open select Results to USB and press ENTER to close Display indicates Closing the Results File If the user leaves the file open when the setup 15 recalled the user will be prompted for a file name Page 40 Operation When multiple tests are being conducted the results are stored to the flash drive periodically every 10 measurements from an internal buffer CAUTION To store all results close the
18. range based on prior knowledge of the expected results NOTE When measuring in the current mode in order to calculate the unknown resistance the input resistance of the instrument 5 must be taken into consideration For further discussion of this refer to Display Type in Paragraph 2 6 3 1 The measurement range capability 1 represented graphically in Figure 2 14 By locating the charge voltage on the vertical axis and the measured resistance or expected measured resistance on the horizontal axis one can determine the optimum range When Auto Range is selected the range switching is done automatically and the specified instrument accuracy always applies If a range other than Auto 15 selected and the resistance value for the given voltage falls outside the range band shown the measurement accuracy specified does not necessarily apply Operation Page 33 950 O oO lt Measurement Ranges at Specified Voltage 1mA 100uA 10uA 1uA 100nA 10nA 1nA 1000 j j j j I I gt 100 10 1 1 00 03 1 00 04 1 00E 05 1 00 06 1 00 07 1 00 08 1 00 09 1 00 10 1 00 11 1 00 12 1 00E 13 1 00 14 1 1 1 GO 1 Resistance Ohms Figure 2 14 Measurement Range Capability Page 34 Operation 2 6 2 8 Limit Utilities 1000 10 1
19. stops with a Fail If the Stop on Pass requirement 1 not met and the measure time has not passed additional measurements are made and averaged The Stop on Pass and measure time requirement are tested after each measurement until one or the other results in an exit from the test cycle When the instrument 15 selected for Manual mode of operation the averaging works similarly When the START button 15 pressed to exit Charge and start measure n measurements are averaged For each consecutive press of the START button one more measurement is made the last five are averaged and result displayed The STOP button exits the Measure mode to discharge the UUT normally Page 36 Operation 2 6 3 Menus Utilities Display Type Result Format RS 232 IEEE Handler Results to USB Figure 2 16 VO Menu The second of the three main menus is I O shown in Figure 2 16 Each function controls measurement results or instrument I O interface and is described in detail in paragraphs 2 6 3 1 through 2 6 3 6 2 6 3 1 Display Type Setup Utilities Display Current Pass Fail Display Figure 2 17 Measurement Display Allows selection from four different modes of measurement display Resistance Current Pass Fail or No Display Resistance mode the 1865 instrument will display the measured value of resistance of the device under test In Current mode the 1865 displays the current to the device und
20. the desired selection or turn a function ON or OFF The ENTER key switches the unit to entry mode and when pressed again initiates the entry or choice selected on the current screen The CNCL key will return the system to main menu display with no changes made From a numeric data field CNCL must be hit twice 22 Startup Check to make sure the line voltage indicator on the rear panel AC inlet module agrees with the AC power source available if not refer to paragraph 1 5 3 Connect the instrument power cord to the source of proper voltage The instrument must be used only with three wire grounded outlets WARNING A flashing CAUTION HIGH VOLTAGE light and or DANGER on the display indicates a defective unit with dangerously high voltages possible at the input terminals Power the unit down and do not use IMPORTANT The interlock connector included with the unit needs to be installed on the rear panel I O Port connector if the interlock function Is not being used Switching POWER OFF and ON quickly may result in error messages Power should be off for at least 10 seconds to assure proper power up Operation Page 21 Power is applied to the 1865 by pressing the POWER button on the front panel The instrument runs a self test and any error messages are displayed accordingly refer to paragraph 2 8 2 3 Zeroing Before making measurements 1865 instrument should zeroed to correct for test lead or fixture errors D
21. the instrument power cord to the source of proper voltage IMPORTANT The interlock connector included with the unit needs to be installed on the rear panel Port connector if the interlock function 15 not being used Press the POWER button on the front panel to apply power To switch power off press the POWER button again or measurements are to be made proceed with Zeroing the instrument discussed in the next paragraph Page 7 Condensed Operating Instructions Zeroing Before measuring zero out test lead or fixture measurement errors as follows l Un 92 If test leads to be used connect them to the 1865 Input terminals red to unknown black to unknown with probes open and spaced some distance apart or fixture open Press MENU key to select menu display Press Right or Left Arrow key to select Utilities menu Press Up or Down Arrow key to select Zero in the sub menu Press ENTER key to activate the Zero routine and follow instructions on the instrument display Auto Measurement Mode In automatic mode once the START button is depressed the instrument sequences automatically through the test cycle phases charge dwell measure and discharge and a pre stored set of test conditions are executed These test conditions can be DEFAULT those at power up set using menus or the operator can recall a previously stored setup l Connect the device under test to the 18
22. to GND Figure 2 4 Three Wire Guarded Connection Grounded or Ungrounded 2 5 Measurement Procedure 2 5 1 General There are two basic measurement modes of operation auto and manual In the automatic mode the test cycle 1s sequenced automatically through four phases Charge Dwell Measure and Discharge in accordance with user programmed times This is the preferred measurement mode especially when the approximate resistance value is unknown since the 1865 instrument employs an auto ranging technique The automatic mode would generally be used in a production environment where measurements are repetitive and setup conditions have been previously established reduce measurement time when making repetitive measurements a particular range may be locked in instead of auto ranging Page 24 Operation In the manual mode the test cycle timing 1s totally at the user s discretion where each of the three phases Charge Measure or Discharge 15 initiated directly by the user This mode would typically be used in an engineering environment or for component evaluation where the measurement results can be observed as test cycle and measurement conditions are altered Whenever the 1865 unit 1s powered up it 1s ready to begin measuring at default test conditions Initially these conditions will be set to a factory default 1 V 0 times Resistance Display Auto ranging and Automatic Mode but can be changed by the user and stored to overw
23. to Utilities Menu P 2 6 4 3 Incorrect password entered Operation PASSWORD NOT SAVED IN RAM PASSWORD VERIFICATION FAILURE RANGE RESISTOR VALUE OUT OF RANGE REMOTE COMMAND INVALID REMOTE COMMAND PARAMETER INVALID REMOTE COMMAND PREFIX INVALID SHUT THE POWER OFF DATE ERROR PLEASE SET UNABLE TO READ FROM USB UNABLE TO READ THAT FILENAME UNABLE TO SAVE CALIBRATION DATA UNABLE TO WRITE TO USB UNABLE TO WRITE TO REMOTE UNKNOWN UNIT VALID RANGE low value hi value VOLTAGE PROGRAM FAILURE Operation Error trying to save password repeat Wrong password entry for verification Malfunction of internal calibration resistors IEEE or RS232 command 15 incorrect for example to set voltage use VOL Tage IEEE or RS232 parameter Is incorrect for example voltage parameter can be XXXX XXX IEEE or RS232 command prefix 15 incorrect for example to configure unit use CONFigure Malfunction of high voltage source Reset time and date Flash drive 15 either not connected or defective selected file unreadable improper format Repeat calibration data not stored Flash drive 1s either not connected or defective IEEE or RS232 not setup correctly or IEEE option not present USB 16 not recognized Entry invalid should be between specified values Malfunction of instrument power supplies Page 63 Section 3 Applications 3 1 Insulation Resistance Te
24. 0 Voltage Charge Time Dwell Time Measure Time 10 Discharge Time 10 Auto Manual gt gt i e 006 0 Stop on Pass to Average 0 In the case where I current 1 selected rather than R resistance the exponent would be entered as a negative number Figure 2 15 Limit Value Resistance or Current Allows entry of a single measurement limit in scientific units up to 4 digits with decimal and exponent for resistance or current depending on the results parameter selected The exponent must be 3 through 14 for resistance or 3 through 13 for current This limit determines the status of the Pass Fail indicator and Pass Fail display when enabled When the 1865 instrument 1s In the Resistance mode the limit 15 a minimum value 1 any value above the limit will result in a Pass whereas a value below the limit will result in a Fail The opposite 1s true when the unit is m the current mode the limit is a maximum value any value below the limit will result In a Pass and a value above the limit will result m a Fail If the display parameter the I O Menu 15 selected as resistance the value entered will be an R limit if the display 15 selected as current the value entered will be an I limit The 1865 s software will check for consistency between the parameter display selected and the limit entered An example of the sequence for entering as a limit would be Press ENTER or Press ENTER Press 1
25. 16 Message Available 4 16 Execution Error Over Range etc _ 3 8 Nn 3 8 X NoContact 2 4 24 Ne d 2 X dX Noe 1112 Nn O 1 Nn 10 l Operation Complete Operation Page 55 This page is intentionally left blank Page 56 Operation 2 7 3 Sample Program for IO Tech GPIB card OPEN dev ieeeout FOR OUTPUT AS 1 IOCTL 1 BREAK PRINT 1 RESET OPEN dev ieeein FOR INPUT AS 2 PRINT 1 fill error PRINT 1 remote 04 PRINT 1 local lockout 14 space 30 15 PRINT 1 output 04 1dn PRINT 1 enter 04 FOR i 1 TO 3000 NEXT 1 INPUT 2 14 PRINT Company identification 15 14 INPUT 2 14 PRINT Instrument identification is 149 INPUT 2 14 PRINT Serial number Is 14 INPUT 2 14 PRINT Software revision is 149 PRINT 1 output 04 syst Dcal PRINT 1 enter 04 INPUT 72 c PRINT This unit was calibrated on c PRINT 1 output 04 100 PRINT 1 output 04 conf lim 9 97e5 PRINT 1 output 04 conf disp r PRINT 1 spoll an error will produce a SRQ INPUT 2 y IF y THEN PRINT 1 spoll 04 INPUT 2 x PRINT spoll 04 x END IF PRINT 1 output 04 MEAS RES y 0 WHILE 0 SRQ at end of measurement PRINT 1 spoll Operation Page 57 INPUT 22 y IF y THEN PRINT 1 spoll 04 INPUT 2 x END IF WEND PRINT 1 output O4 fetc request dat
26. 250V 90 250V T2 5A 5x20mm IEEE 488 INTERFACE RS 232 INTERFACE BATTERY REPLACE D ND D k O EA THREE SIZE AA s s s s TERMINAL OUT PARALLEL VO PORT D ND ED PORT um 250V 7 63Hz ATE D s D MAX D D HED D D HED D a D GED MADE IN USA Figure 1 2 Rear Panel Controls and Connectors Table 1 2 Rear Panel Connectors and Controls Reference Function Number Figure 1 2 AC Inlet Module Black 3 Prong 3 wire connection for AC power source Receptacle amp Fuse 90 250V AC T2 5A 250V 5x20mm Fuse Drawer Rear Panel Portion Instrument ventilation 3 Port 36 pin Male 36 Pin Connector for Component Handler Amp 552302 1 Use with Amp 552302 1 plug amp 552073 5 compatible strain relief cover or ribbon cable clamp connector 553600 1 or equivalent s 4 Parallel Port Not Available Not Available Not Available 0 Option 1865 03 Rear Panel Input Terminals Ground and Guard for connection to DUT with High Voltage Indicator 3 AA batteries need to be replaced SM m 8 4882 Interface 24 pinMale 7 24 pinconnectorforObsolete 0 Page 16 Introduction 1 4 Installation 1 4 1 Dimensions The instrument is supplied in a bench configuration 1 in a cabinet with resilient feet for placement on a table A bail is provided under the front edge so that the instrument can be tilted
27. 65 test leads or other fixture being used 2 If desired setup conditions are anything other than DEFAULT set using menus or proceed to Recalling Setups below before continuing with step 3 Initiate the auto measurement mode by pressing START The High Voltage Indicator will remain on as the unit sequences automatically through all four phases charge dwell measure discharge of the test cycle The measurement can be aborted at any time during the test cycle by pressing STOP Once the High Voltage Indicator goes off the measurement is complete the final result remains displayed and the device can be removed Page 8 Condensed Operating Instructions Manual Measurement Mode In manual measurement mode each phase of a test cycle charge measure and discharge is initiated manually at the users discretion These test conditions can be DEFAULT those at power up set using menus or the operator can recall a previously stored setup 9 Connect the device under test to the 1865 test leads or other fixture being used Press MENU key to select menu display Press Right or Left Arrow key to select Setup menu Press Up or Down Arrow key to select Mode in the sub menu Press ENTER to activate the selection field Press Right or Left Arrow key to select Manual and press ENTER If the desired setup conditions are anything other than DEFAULT set using menus or proceed to Recalling Setups below be
28. 71 LCD Display Keypad Panel The front panel user Interface consists of a molded silicon rubber keypad that actuates a membrane switch assembly keypad is environmentally sealed designed for long life and all keys provide tactile feedback to the operator The 2 1 2 x 4 3 4 LCD 1s a high resolution graphic display with on off backlight for visual clarity Both keypad and display are connected to the instrument I O board via ribbon cables 4 2 2 1865 Instrument Modules Analog Instrument Board The analog instrument board is the heart of the 1865 It includes the measurement detector high voltage source and bus interface to the processor This board also contains a non volatile memory in EEPROM electrically erasable programmable read only memory for retaining vital calibration information This 1s the main board in the instrument compartment to the left of the power supply modules All other boards are mounted to it A brief description of the operation of the measurement detector 1s as follows Figure 4 1 shows the basic block diagram for the measurement module A programmable high voltage 0 1000V Is applied to the unknown component Rx The current flowing through the unknown 15 measured by the current to voltage converter whose output 1s applied to the A D for processing by the instruments CPU The measured results can be expressed El Rs Rx Ex This technique is dependent upon accuracy of the applied vol
29. EPT THE CONTRAST SETTING Figure 2 31 Display Contrast Adjustment 2 6 4 10 LCD Backlight Allows backlight on the LCD display to be turned ON or OFF Turning backlight off when it 1s not needed or if the display 1s not In use Keeping the backlight off prolongs the life of the display 27 Input Output Interface 2 7 1 Interface The 1865 instrument comes standard with an I O interface port available through a connector 36 pin on the rear panel of the instrument This is generally used for interfacing to an automatic component handler Refer to Table 2 3 for signal names pin numbers and functions as necessary for cable connections Page 50 Operation Table 2 3 Interface Connections Input GND 1 453 System Ground 00 tor 29 EndofTestBinsignalouputsvalid Interlock INTERLOCK Operator Safety feature primarily for use with external fixtures 1 operation of the 1865 instrument can be disabled until the cover of the fixture 1s closed To enable the interlock function pin 31 must be connected to ground or controlled electrically with a logic low This can be converted to an isolated active low input by removing jumper JP4 on the I O PCB The interlock connector supplied with the unit makes this connection pin 31 to 28 when plugged into the rear panel I O connector Figure 2 32 N H 36 Figure 2 32 Rear Panel I O Connector WARNING Do n
30. NNNNE NNN 2 spaces PASS The plus sign will be negative when the parameter 1s selected as current Pass can also be Fail or neither if no limit is entered IDN Returns instrument identification IET 1865 0 software version START Initiates a measurement in Auto mode in Manual mode it initiates charge if sent again it takes one measurement each time sent thereafter one additional measurement 15 taken STOP Stops a measurement in process in Auto mode in Manual mode it exits the measurement loop to discharge if sent again it exits discharge CALibrate DATA Returns the calibration data to the user 21 values see next page ZERO Instrument zero NOTE When a Bad Zero Calibration message 15 returned query the IEEE for an error using the ESR for a decimal value of 16 for an execution error Looking at the execution error prevents an automation program from hanging while waiting for the instrument to make a measurement and return a value Page 54 Operation Table 2 5 IEEE and RS 232 Commands Continued Description of the 21 values returned by the remote CAL DATA I The value of the Internal voltage standard 2 The 100 volt full scale value 3 The 1000 volt full scale value 4 The gain of the 500 1 voltage attenuator 002 5 The gain of the 50 1 voltage attenuator 02 6 The gain of the 5 1 voltage attenuator 2 7 The input resistance 8 value of the range 1 standard 2 9 The value
31. PPLIED to initiate the ZERO CALIBRATION which takes approximately 75 seconds 10 Once zero calibration 1s complete 1f the time and date are correct as displayed answer Y yes to store the calibration data If they are not correct press N no to change date and time as instructed To prevent the calibration from being changed by mistake the instrument requests final confirmation before the data 1s saved Once this 15 complete MENU selected the calibration 15 COMPLETE Service amp Calibration Page 79 Section 6 Optional Accessories 6 1 1865 11 Resistivity Test Fixture Resistivity Test Fixture reads resistance only and with unique formulas it will convert resistance into Surface Resistivity and Volume Resistivity Measuring resistance through the fixture 1s theoretically and conceptually the same as measuring without the fixture Volume Resistance is the Resistance through the chosen material whereas Surface Resistance is the Resistance on the surface of the chosen material This Resistivity Fixture will allow a stable and accurate measurement despite external radiation leakage 6 1 1 How to connect the fixture The following items are necessary to connect the 1865 11 Resistivity Test Cell to the 1865 Megohmmeter Use the listed cable assembly or the provided cable assembly rather than miscellaneous adapters to permit proper correction of cable and lessen related error and system leakage Use only the fixture that corre
32. Press 1 Press e select key Press 0 zero three times Press 6 exponent multiplier Press e select key Press ENTER Press 3 Press ENTER Operation Page 35 2 6 2 9 Stop on Pass Accepts entry of a value between 0 and 300 which is the number of consecutive passing measurements that must occur to exit the measure loop before the measure time has passed This 1s only active when there Is a measure time and limit specified An entry of 0 disables the stop on pass function 2 6 2 10 to Average Accepts entry of a value between 0 and 400 which 1s the number of measurements to be averaged and displayed If the value 15 O or averaging 15 disabled and the display 15 updated with each measurement if the value is n between 2 and 400 the average is displayed after n measurements If the measure time has not elapsed after the first averaged display then a running average of measurements 1s made until the measure time is up For example if n 15 5 the first five measurements are made averaged and then displayed The sixth measurement 1 averaged with the last four and the first 1gnored this continues until the user specified measurement time 1s complete When Stop on Pass 15 In effect n measurements are made and averaged If the Stop Pass requirement 15 met the cycle stops with a Pass even though the measure time has not passed If the measure time has passed and the Stop on Pass requirement has not been met the cycle
33. SS PASS 2 6 4 Utilities Menus Setup Recall Setup Zero Lock Out Calibration Set Time Date Elapsed Time Calibration Date Set Contrast D Backlite Figure 2 21 Utilities Menu Utilities gt gt gt gt gt gt gt gt gt gt The last of the three main menus 15 Utilities shown in Figure 2 21 Each function 1 described in detail In paragraphs 2 6 4 1 through 2 6 4 10 Page 42 Operation 2 6 4 1 Save Setup NEW DEFAULT USB 1865 1 1865 2 1865 3 1865 4 Figure 2 22 Save Setup Test Conditions Allows a set of test conditions to be stored In Instrument memory or on the USB flash drive for later recall Test conditions are those that are user programmable in the Setup and I O menus refer to paragraphs 2 6 2 and 2 6 3 above Stored setup conditions should always be backed up on a flash drive or recorded on paper NOTE To store setups in the 1865 s internal memory a flash drive must be plugged into the USB port To store the current set of test conditions as a new set in unit memory you need to select NEW in the Save Setup menu and enter the identifying name up to 8 characters under which these conditions will be stored allowable characters from the keypad include 0 through 9 and minus characters can also include A through Z when operating from remote control To save the setup under the name selected or to overwrite if the name alre
34. a PRINT 1 enter 04 get data INPUT 22 c PRINT c PRINT 1 output 04 system lock 0 enable front panel PRINT 1 local END 2 7 4 RS232 Interface The 1865 instrument comes standard with an RS232 serial port interface available through a connector 9 pin on the rear panel of the instrument for connecting to a PC The RS232 standard defines electrical specifications for the transmission of bit serial information The use of the RS232 port requires five lines receive data transmit data data terminal ready data set ready and signal ground With some controllers additional signals maybe required and are listed in Table 2 6 Refer to Figure 2 34 for null modem cable configuration to the standard db9 or db25 connector Refer to Table 2 5 for the command set which also applies to the RS232 interface When using the RS 232 interface with a printer the 488 2 Mode must be set to Talk and the State to Disable Table 2 6 RS232 Interface Connections Signal Name Pin Number Function Input DCD I Data Carrier Detect DSR 6 Data Set Ready RXD 2 Receive Data CTS Clear to Send RI 9 Ring Indicator Outputs RTS 7 Request to Send TXD 3 Transmit Data DTR 4 Data Terminal Ready GND 5 signal Ground Page 58 Operation db9 to db9 Cable Configuration 1865 P Funcion Receive data Connect Transmit data Transmit data to Receive data Data terminal ready Data set ready signal ground signal gro
35. ady exists answer Yes or No Figure 2 23 Operation Page 43 Setup Utilities SAVE AS XXXXX N Figure 2 23 Save Overwriting Setup To make the current set of test conditions the default at power up one needs to select DEFAULT in the Save Setup menu and overwrite the conditions currently stored prevent overwriting the default setup by mistake an additional level of safety exists where the operator 1s required to respond with Yes or No similar to Figure 2 23 selecting del will delete a set of test conditions and requires a Yes or No confirmation When there are more setups than can fit on the display the page down key is active If there 1s less than a whole page below the display wraps around to the previous display Continuing to page down will eventually return to the first display of setups The page down key 1 only shown when there are more setups than what 1 visible There are two ways to make the current set of test conditions overwrite an existing setup One 15 to select that setup the menu and answer Yes to overwrite The other way 1 to enter the same name under New and answer Yes to overwrite Setup Utilities Save 1865 100 1865 102 1865 103 4 1865 104 Figure 2 24 Saving Setups on a flash drive Page 44 Operation It 15 possible to store about 25 sets of test conditions In the 186575 memory and more than 1000 setups can be stored on a flash drive via the USB por
36. back for convenient operator viewing 1865 DISPLAY SELECT ENTRY TEST 133 4mm 406 4mm lt 444 5 Ee Figure 1 3 1865 Instrument Dimensions 1 4 2 Instrument Placement The 1865 instrument contains a high resolution back lit LCD for convenient viewing The optimum angle for viewing 15 slightly down and about 30 either side of center This means that for bench operation the front bail should always be used to angle the instrument up and for rack installation it should be mounted at eye level or higher 1 4 3 Power Requirements A The 1865 Megohmmeter IR Tester can be operated from a power source between 90 and 250Vac at a power line frequency of 47 to 63Hz Power connection to the rear panel is through an AC inlet module comprised of an ac connector and fuse drawer Before connecting the 3 wire power cord between the unit and ac power verify that the fuse is 2 5 A 250 V slow blow 5x20 mm Always use an outlet which has a properly connected ground The standard 1865 is factory shipped with the 2 5A fuse in place The instrument can be damaged if the wrong fuse is installed To change the fuse proceed as follows Introduction Page 17 PROCEDURE FOR CHANGING A FUSE WARNING Make sure the unit has been disconnected from its ac power source for at least five minutes before proceeding Fuse drawer with release tab
37. cated above the mode indicates Manual rather than Automatic Default and other stored setups can still be recalled the only difference being that the test cycle times are not applicable MANUAL MEASUREMENT MODE Charge Voltage appliedto lt UUT Ya Charge t Measure t Discharge t S gt Test Cycle Time Manually Controlled START START STOP STOP High Voltage High Voltage Indicator On Indicator Off Note A single measurement will be made in the measure phase each time START is pressed Figure 2 8 Test Cycle Sequence Manual 26 Menu Functions 2 6 1 General All programmable functions of the 1865 are controlled by easy to use menu displays The user enters the menu mode by selecting the MENU key which calls up three top level menus Setup I O and Utilities Each one of these 1s comprised of a sub menu list whose functions are described in detail below Navigating around the menu listing Is accomplished in a fashion similar to an Automatic Teller Machine ATM using the up down right and left arrow keys as indicated on the adjacent LCD display A highlighted menu function can be controlled by pressing the ENTER key making the desired entry or selection and pressing ENTER again to implement Page 28 Operation 2 6 2 Setup Menus Utilities Charge Time Dwell Time Measure Time Discharge Time Mode Limit gt gt 100 9
38. ckness 8mm Test Fixture Max Sample Size 100mm x 100mm i e e UR SS lt sC sv o Outer Ring Electrode e imm r e Inner Ring Electrode Timm Electrode a Function FUNCTION CU Pish Button 1 Lack Clase Fixture 1 J Figure 6 2 Connection of an 1865 11 Test Cell to an 1865 Megohmmeter Optional Accessories Page 81 6 1 2 Theory of Resistivity Test Fixture Operation WARNING Do not open the fixture while voltage is present at its output Any material that holds charge be hazardous until completely discharged There are two methods of reading resistance yet each 15 used very differently The first and most commonly used method for reading high resistance megohm range 1 the constant voltage method In this method voltage 15 applied in series with the resistor or this case an insulator and a current meter This will allow a known high voltage to pass through the resistor while the current meter detects the amount of current electrons that passes through the barrier resistor or insulator Using Ohm s Law for resistance R V D the resistance of the insulation can be calculated in today s world measured The second method commonly used 15 a conductivity test The conductivity test applies known measured current through the resistor and measures the voltage drop across the resistance This method has been used at a high
39. consideration except for capacitors greater than 10 uF so Capacitors with high dielectric absorption can have a residual charge even after they are shunted and must be repeatedly shunted to completely discharge Usually a voltage recovery of this type would be a very small percentage of the original applied voltage and generally not dangerous to the operator This risk 1s further minimized by the fact that the 1865 circuitry remains in a discharge mode until the operator initiates another charge and measure cycle Page 68 Applications 3 4 Resistance Measurements The recommended test voltage 1s typically 100 V for fixed composition resistors film resistors or wire wound resistors above 100 Refer to the component manufacturers recommended test voltages These resistors values greater than 1000 can easily be measured on the 1865 where the instrument basic accuracy of 0 5 1s adequate For single component resistors two terminal connection UNKNOWN and UNKNOWN Is recommended 3 5 Measurement of Voltage Coefficient The 1865 instrument may be used to measure voltage coefficient which is defined as orum x 100 R2 V1 V2 where V1 V2 1s the resistance at V1 the higher voltage R2 1s the resistance at V2 For example if V1 500 V and V2 100 V Rsoov Rioov Voltage Coefficient x 100 Rioov 400 AR 0 A Rioov This voltage coefficient 1s usually negative
40. e possibility exists that full charge voltage may not be reached at the start of the measurement phase if the DUT has a long time constant NOTE For low voltage measurements 5 V a minimum charge time of 2 seconds 1 recommended to meet the instruments stated accuracy 2 6 2 3 Dwell Time Accepts entry of a dwell time or electrification time between 0 and 300 seconds in second intervals This 15 a time during which the test voltage 15 applied to the device under test and prior to any measurement 2 6 2 4 Measure Time Accepts entry of a measure time between 0 and 999 seconds in 1 second intervals This is the time during which repeated measurements are made and results displayed as resistance current Pass Fail or no display depending on the results format selected The display 1s updated each time a measurement ts made during this time phase Page 30 Operation 2 6 2 5 Discharge Time Accepts entry of a discharge time between 0 and 300 seconds in 1 second intervals This is the time when the test voltage 1 removed and the device under test discharged The CAUTION HIGH VOLTAGE lamp goes OFF at the end of the programmed interval and the last measurement result 15 retained on the display unless no display 15 selected 2 6 2 6 Mode Utilities Voltage 1000 Charge Time Dwell Time Measure Time Discharge Time Mode Auto Range Limit Stop on Pass Figure 2 12 Measurement Mode Selection Allows
41. e 75 Battery Compartment O IEEE 488 INTERFACE 7 Uu C AC BATTERY an C 2 PORT C pare C 2 of C gt D iS PARALLEL PORT RS 232 INTERFACE 90 250 V I E E 47 63 Hz C 2 is 4 40 WATIS 5 1 2 w Figure 5 1 Battery Compartment Resetting of Time and Date If for some reason the backup power supplied by the 3 AA batteries should fail during shipment of the instrument due to shock vibration or extreme temperature the unit will lose its zero time and date elapsed time and stored setup conditions An indication of such an occurrence would be the display of the error message ELAPSED TIME ERROR SET TO 0 when the unit is first powered up The most likely cause would be an intermittent connection to the battery due to shock or vibration It is very important that the time and date be reset and the instrument zeroed before proceeding with any measurements Proceed as follows es p Page 76 Press MENU key to select menu display Press Right or Left Arrow key to select Utilities menu Press Up or Down Arrow key to select Set Time Date Press ENTER key to activate the entry field set
42. ece ud ep D eR ed Mehr udi dc 21 Ec 23 2 2 CaliDrattonu POCO QUEG uso diaeta Optional Accessories Section 6 6 1 1805 11 Resistivity Test PIXU G eto dnte e entere Howto connect TAUTE uu uyu Ebo t out hoe idt tae dud 6 1 2 Theory of Resistivity Test Fixture Operation 6 1 3 mde Mm asna OA Volume u u a uhu 6 1 5 Cleaning the Resistivity Test Fixture Page v Page vi Resistance Range Specifications 1 103 to gt 1 1014 O dependent on test voltage 1 106 gt 1 1014 9 at 1000Vdc 1x10 1 1013 Q at 100Vdc 1x104 1x1012 Q at 10Vdc 1x10 1 1011 Q at 1Vdc 7 ranges or auto ranging Resistance Accuracy 0 45 Rx Vx 0 0005 FS 2pA 30Q Rx 100 Voltage Range Voltage Accuracy Output Voltage Impedance Current Limited Current Measure Current Accuracy Input Impedance Measure Limits Display Rx Measured resistance In ohms Vx Programmed voltage in volts FS Full scale current range In amperes to 1000 V programmable in two ranges 1 100 V 1 of setting 1 V 25mV resolution 100 1000 V 196 of setting 2 V 250 mV resolution 1 5 lt 2mA 1 10 13 to 1 10 3 amps InA to ImA 0 5 0 0005 FS 2 pA 100pA to InA 1
43. enter a password number up to 8 characters CAUTION For security reasons the password is not displayed when it is entered so the password should be keyed in carefully and remembered ENTER PASSWORD 8 CHARACTERS MAXIMUM CK CK kK GR K Once the password 1s entered and entered again for verification testing can begin by pressing START or the password cleared or changed by selecting MENUJ HIT lt gt KEY TO ENTER PASSWORD AND TO RETURN TO THE MENU OR HIT THE START KEY SIART A MEASUREMENT Once activated only the START STOP and MENU on the instrument front panel are active all other keys are disabled To turn the lockout feature off and reactivate menus select MENU select Exit Lockout in Lockout with Setup Recall mode and enter the previous password from the keypad the instrument will again function as normal Failure to remember an entered password requires an override password 186501 If Recall Setup is chosen in the Lockout with Setup Recall mode the instrument functions as described in paragraph 2 6 4 2 under Recall Setup 2 6 4 5 Calibration Refer to Calibration in Paragraph 5 4 INSTRUMENT CALIBRATION SHOULD BE PERFORMED ONLY BY QUALIFIED SERVICE PERSONNEL Operation Page 47 2 6 4 6 Set Time Date Tue Jan 14 10 37 10 1992 TO CHANGE TIME PRESS T KEY TO CHANGE DATE PRESS KE TO RETURN PRESS lt MENU gt D Figure 2 28 Set Current Date and Time All
44. er test In Pass Fail mode the actual measured value 16 displayed small font along with a Pass or Fail based on the measurement limit entered which could apply to either resistance or current Operation Page 37 In No Display only the voltage mode and range are displayed with no measured value This might be used for security reasons or for the purpose of reducing test time during remote operation When the display 1s selected as current you need to keep mind that the 5 input impedance and the 1 output voltage source impedance of the unit are in series with the unknown For low values of resistance 20 the measured current would be Charge Voltage Zin Zoytt Runknown 2 6 3 2 Result Format Display Type Result Format Sci Results to USB Figure 2 18 Measurement Results Format Allows selection from two different measurement result formats Sci or Eng for scientific or engineering units Scientific units are expressed as an exponent and engineering units are expressed in ohms for resistance and amps for current For example in scientific units can be expressed as MQ or as uA in engineering units This is strictly for the user s convenience When Sci is selected the results will always be displayed as 5 digits and an exponent The 5 digits will be configured as 1 to the left and 4 to the right of the decimal point When Eng is selected the results will be displayed with a minimum of 4 and
45. esistance measurements on insulating materials and components It 1s designed for easy accurate and direct readings of high resistance typically found in synthetic resins porcelains insulating oils plastics and other similar materials It is also used for measurements on capacitors transformers switches cables and connectors The 1865 provides a direct readout of resistance from 1000 Q to 1000 with fully automatic ranging The voltage applied to the unknown is programmable from 1 V to 1000 V The 1865 includes a high resolution graphics display and keypad for ease of use The test cycle 1s fully automatic with programmable charge dwell measure and discharge times These times along with other test conditions can be stored in instrument memory and recalled for later use pass fail indicator provides the operator with a visual indication based on a preset resistance limit The unit also contains automatic zeroing at the test leads as well as built in self test routines Safety features include current limiting to less than 2 mA and a front panel indication when voltage 15 applied to the test terminals thus permitting connections to be made safely The 1865 comes standard with I O Port handler and RS232 interface An IEEE 488 2 to RS 232 Interface Adapter 1 optional for remote control operation A USB host port connection 15 available for storing test conditions and results on a flash drive There 1 a direct reading current measurement
46. fic e AC Power Cable e and 100 Capacitor Adapters e nstruction Manual e Calibration Certificate e nterlock Connector 1865 50 Rack Mount Kit e 1865 51 Shielded Lead Set e 1865 52 Component Test Fixture Accessories Accessories Included USacPowerCaBe kpeng 4300 030 2 5 250 V5X20mmLineFuse 1 5009 Accessories Options Available Shielded Lead Set 118651 Component Test Fixture 1 1 5 52 Resistivity Test Fixture 18651 Page 3 Page 4 Safety Precautions WARNING The 1865 Megohmmeter IR Tester can supply an output voltage as high as 1000 Vdc to the external device under test DUT Although the 1865 unit 1s designed with full attention to operator safety serious hazards could occur 1f the instrument is used improperly and these safety instructions are not followed l The 1865 unit 15 designed to be operated with its chassis connected to earth ground The 1865 instrument 15 shipped with a three prong power cord to provide this connection to ground The power cord should only be plugged in to a receptacle that provides earth ground Serious injury can result if the Sentry unit is not connected to earth ground 2 Tightly connect cable s to the green GND terminal If this 1s not done the DUT s casing be charged to the high voltage test level and serious injury or electrical shock hazards could result if the DUT 1s touched 3 Never touch the metal of the High Voltage
47. file before shutting down the power To keep measurement results consistent with the setup conditions close the file before changing or recalling a new set of test conditions The measurement results one for each complete measurement cycle are stored as a DOS text file under its assigned identifying number up to 8 characters with an extension of 65R The test setup conditions are saved as a header at the beginning of a results file sample file format Is shown below Notice that the results can be stored in either engineering or scientific terms depending on what the user has selected for setup conditions 100 000000 0 000000 0 000000 0 000000 0 000000 0 000000 0 000000 1000000 000000 0 000000 1 0 000000 000000 3 000000 0 000000 1 000000 0 000000 4 000000 1 000000 0 000000 1 000000 0 000000 1 000000 ENDHEADER Operation voltage charge time dwell time measure time discharge time mode 0 auto 1 manual grange limit on pass to average display type result format baud rate 0 1200 1 2400 2 4800 3 9600 parity data bits stop bits IEEE address IEEE mode IEEE state handler result to USB sbacklight 0 off 1 on Page 41 1 020 M ohmPASS 1 020 M ohmPASS 1 020 M ohmPASS 1 020 M ohmPASS 1 020 M ohmPASS 1 020 M ohmPASS or 1 020015 006 1 020015 006 1 020015 006 1 020015 006 1 020015 006 PASS PASS PASS PA
48. fore continuing with step 8 Setup measurement times are Ignored in manual mode Initiate the charge phase by pressing START to apply high voltage to the device The High Voltage Indicator will remain on as long as a voltage 1s applied The measurement can be aborted at any time during the test cycle by pressing STOP Initiate a single measurement by pressing START again The measured result will be displayed on the LCD and will be updated each time START is pressed 10 To discharge the device press STOP 11 Before removing the device press STOP again to end the discharge phase and turn High Voltage Indicator off Recalling Setups To recall a set of test conditions previously stored Press MENU key to select menu display Press Right or Left Arrow key to select Utilities menu Press Up or Down Arrow key to select Recall Setup Press ENTER key to activate the recall entry field Press Up or Down Arrow key to select the desired setup choices are DEFAULT if conditions are power up which can be changed by the user USB if setup 1s to be recalled from a flash drive Setup Name stored in the instrument internal memory or USB Once the desired setup is located press ENTER key to finalize recall of the setup conditions Page 9 Condensed Operating Instructions Saving Setups 1 To save the current set of test conditions as entered conditions include voltage test times measurement range lim
49. forming to IEC 320 and units are supplied with an approved international cord set Make sure the instrument is only used with these cables or other approved international cord set which ensures the instrument is provided with connection to earth ground When the 1865 instrument is used in a rack installation using the 1865 50 Rack Mount Kit make sure the unit is secured using the cabinet mounting rails and not secured solely by the front panel angle brackets In bench or rack mount applications the instrument should be positioned with consideration for ample air flow to the rear panel ventilation holes An open space of at least 3 inches 75 mm is recommend behind the rear panel The surrounding environment should be free from excessive dust to prevent contamination of electronic circuits WARNING If this instrument is used in a manner not specified in this manual protection to the operator and equipment may be impaired Read this instruction manual in full before operating this instrument Introduction Page 19 Section 2 Operation 2 1 Terms and Conventions The names of keys in the manual will generally appear in CAPITAL LETTERS The MENU key calls up the main menu display and returns to the line previously selected The gt gt symbol on a menu indicates a lower level menu exists The select keys generally function as UP DOWN LEFT and RIGHT arrow and allow you to move through a menu or field of choices to make
50. ge measurements on high value capacitors This 15 due to the fact that a capacitive element 15 very ac sensitive and the dc voltage applied to the device always contains a small percentage of low frequency noise ripple Measurements on pure resistive elements will tolerate a high degree of ripple due to the voltage ratio measurements whereas a capacitor easily passes the noise ripple When this is amplified by the current amplifier of the measuring instrument results can fluctuate and vary widely To eliminate this in the 1865 two resistance adapters are supplied which can be placed in series with the unknown black when measurements are made on the low current ranges the IMQ Hi Range Adapter is recommended for ranges InA amp 10nA and the 100kQ Lo Range Adapter for ranges 100nA amp 10uA This added resistance has negligible effect on the dc measurement since its value 1 very small compared to the leakage resistance of the unknown however it increases the ac input resistance to the current amplifier reducing the ac gain and thus minimizing the wide fluctuations This added resistance will have an effect on the charge time constant and 15 discussed briefly in paragraph 3 3 2 below WARNING Capacitors being measured may be charged and contain lethal energy Always make sure the CAUTION HIGH VOLTAGE Indicator is OFF when connecting or disconnecting the capacitor under test Applications Page 67 3 3 2 Charge Time Constant The ti
51. istance The surface resistivity can be calculated in two ways hard or easy The hard way means substituting the 1865 11 test cell dimensions into formulas for Current Density and Surface Current Density Pull out the old Calculus and Physics books and convert these formulas for a circular electrode configuration The easy is way 15 finding the area of two different circles and subtracting them The space between two concentric objects is known as the annulus This resistivity is calculated using the modified version of Ohm s law where ps Rs x L x W for a quadrilateral or in the case of the QuadTech Resistivity Test Cell an annulus ps Rs x A Q cm where A z b and a gt b a 3 5 cm radii for the outer electrode b 2 5 cm radii for the inner electrode Supplementing values into the equation it gives a constant value of 18 84955 cm Therefore if the measuring device reads 2 20 MQ for the Rs value multiply that value by 18 84955 cm ps Rs x A 2 20 MQ x 18 84955 cm 41 46901 MQ cm According to the ASTM D257 99 2005 standard the formula for Surface Resistivity of a circular electrode 1s ps Rs x P g Q where x D D D1 D2 2 D1 diameter of inner electrode D2 diameter of outer electrode g 1s the distance between them Note g be factored out only if the thickness of the sample is much smaller than g 1 lt lt 8mm 8mm is the max thickness of the QuadTech Resistiv
52. it and display modes Press MENU key to select menu display Press Right or Left Arrow key to select Utilities menu Press Up or Down Arrow key to select Save Setup Press ENTER key to activate setup entry field Press UP or Down Arrow key to select the desired setup choices are NEW if a setup 1s to be saved in instruments internal memory DEFAULT if conditions at power up are to be changed and restored USB if a new setup 1s to be stored or existing one changed on the flash drive Setup Name if an existing set of conditions are to be changed in the instrument internal memory or a flash drive Press ENTER key to activate the Save entry field selected above If NEW 15 selected internal memory or USB enter the desired identifying name up to 8 characters under which these set of test conditions will be stored Press ENTER key to finalize storage of the setup conditions or if DEFAULT is selected one must answer Y or N to overwrite Changing Test Voltage 1 Set the desired test voltage Press MENU key to select menu display Press Right or Left Arrow key to select Setup menu Press Up or Down Arrow key to select Voltage Press ENTER key to activate the voltage entry field Enter desired test voltage up to 5 digits with decimal between 1 and 1000 V Press ENTER key to finalize the voltage entry Changing Measurement Times 1 To set the desired measurement cycle times charge dwell measure and discharge Press
53. ity Test Cell TOP Electrode Figure 6 3 Surface Resistance 6 1 4 Volume Resistivity Optional Accessories Page 83 Volume Resistance 15 defined as the electrical resistance between opposite faces of an insulating material This resistance 15 calculated using the simplified version of Ohm s law Rv V Iv where Rv Volume Resistance Iv Volume Current V Applied Voltage Volume Resistivity is defined as the electrical resistance through a specific volume on one side of a material to the opposite side In other words the measured resistance 1s multiplied by the cross sectional area and divided by the trajectory path the current must travel This resistivity 1s calculated using the modified version of Ohm s law where p Rv x L x W t for a quadrilateral electrode or in the case of the QuadTech Resistivity Cell a cylinder p Rv x AJ t Q cm where A x b or x D1 y4 b 2 5 em radii for the inner electrode D1 5 cm diameter of inner electrode t thickness of sample needs to be 8mm Supplementing values into the equation it gives a constant value of 19 634554cm Therefore if the measuring device reads 20 20 for the Rv value and the sample has a thickness of 3 3mm 0 33cm then multiply that value by 19 634554cm p Rv x 20 20 MQ x 19 634554 cm 33cm 1 201872GQ cm According to the ASTM D257 99 2005 standard the formula for Volume Resistivity of a circular electrode 1s
54. le Theory Page 73 Section 5 Service amp Calibration 5 1 Routine Maintenance Routine maintenance of the 1865 instrument includes battery replacement time amp date resetting display contrast monitoring preventative cleaning and calibration 5 1 1 Battery Replacement CAUTION To avoid damaging the unit replace the batteries annually Backup power for the instrument s non volatile memory is supplied by 3 standard batteries These should be replaced annually with alkaline batteries otherwise damage to unit is possible as a result of battery leakage IET will assume no responsibility for instrument damage resulting from the batteries not being changed as recommended To replace the batteries refer to figure 5 1 and proceed as follows 1 Turn the instrument on and make sure it is not in measurement mode CAUTION If the batteries are removed with the power off there would be no power to the non volatile memory and important data such as stored test conditions would be lost 2 Place a flat head screwdriver in the groove of the battery compartment end cap and rotate counterclockwise CCW about 1 4 turn to remove 3 Lift the front of the instrument up slightly so that the batteries slide out of the compartment 4 Install three new batteries positive side out CAUTION Do not install the batteries backwards 5 Reinstall the end cap and rotate clockwise CW to secure Service amp Calibration Pag
55. lified personnel HIGH VOLTAGES MAY BE PRESENT AT THE TERMINALS OF THIS INSTRUMENT WHENEVER HAZARDOUS VOLTAGES gt 45 V ARE USED TAKE ALL MEASURES TO AVOID ACCIDENTAL CONTACT WITH ANY LIVE COMPONENTS USE MAXIMUM INSULATION AND MINIMIZE THE USE OF BARE CONDUCTORS WHEN USING THIS INSTRUMENT Use extreme caution when working with bare conductors or bus bars WHEN WORKING WITH HIGH VOLTAGES POST WARNING SIGNS AND KEEP UNREQUIRED PERSONNEL SAFELY AWAY AN CAUTION DO NOT APPLY ANY VOLTAGES CURRENTS TO THE TERMINALS OF THIS INSTRUMENT IN EXCESS OF THE MAXIMUM LIMITS INDICATED ON THE FRONT PANEL OR THE OPERATING GUIDE LABEL Contents SpeciHca 1 eer S 1 Su 3 Safety a qas ss u 5 Condensed Operating Instructions 10 Introduction Section 1 1 1 Unpacking and uu uu etie bait ushanaka 13 1 2 PHOGUCE 13 1 3 Controls and IndiedlOES u uuu Ak 14 1 3 1 Front Panel Controls and Indicators 14 1 3 2 Rear Panel Controls and Connectors 16 1 4 lis lli NN RENE 17 14 Dimens 2220 zu nuchi as mu as h nisu h Sum 17 14 22 Instrunient Placement u uy
56. lue Figure 2 7 AUTOMATIC MEASUREMENT MODE Charge Voltage applied to UUT Charge t Dwell t Measure t Discharge t 0 300s 0 300s 0 300s 0 300s START or 0 999 High Voltage High Voltage Indicator On Test Cycle Time Programmable Indicator Off on later units Figure 2 5 Test Cycle Sequence Automatic Page 26 Operation Measurement Value Measurement Parameter Measurement Units Resistance or n Engineering or Scientific N ESISTANCE 1 Q 0 Test Cycle Status Charge Dwell Measure or Discharge MEASURE p n VOLTAGE 1000 LIMIT 9 0 e 005 Pass Fail Limit Charge MODE AUTO RANGE 10 uA A REMOTE Measure Mode Keypad Disabled Fullscale Measurement Range Auto or Manual can indicate REMOTE denotes autorange or LOCKOUT Figure 2 6 Measurement Results Display with Value Results Displayed in the Result Format Scientific or Engineering 9 0 e 005 ohms MEASURE VOLTAGE 1000 LIMIT 9 0 e 005 MODE AUTO RANGE 10uA REMOTE Figure 2 7 PASS FAIL Results Display Operation Page 27 2 5 4 Manual Measurement Mode The primary difference between automatic and manual modes 15 that In the manual mode the phases of the test cycle must be initiated manually by the user Here there are three phases rather than the four in automatic the Dwell function 1s part of the Charge phase The results are still displayed in the manner indi
57. ly careful The High Voltage Output 1s being turned on and off with an external signal Page 5 Safety Symbols The product is marked with the following safety symbols A Product will be marked with this symbol ISO 3864 when it is necessary for the user to refer to the instruction manual in order to prevent injury or equipment damage Product marked with this symbol IEC417 indicates presence of direct current A Product will be marked with this symbol 150 3864 when voltages in excess of 1000V are present Indicates the grounding protect terminal which is used to prevent electric shock L from the leakage on chassis The ground terminal must connect to earth before using the product Warning Procedure can cause hazard to human if the warning is neglected Caution Avoid product misuse It may cause damage to the product itself and the DUT if the caution 1 neglected Note Important information or tips for the procedures and applications Warning Signal During Testing DANGER HIGH VOLTAGE TEST IN PROGRESS UNAUTHORIZED PERSONS KEEP AWAY Disposal Do not dispose of electrical appliances as unsorted municipal waste use separate collection facilities Contact your local government for information regarding the collection systems available If electrical appliances are disposed of in landfills or dumps hazardous substances can leak into the groundwater and get into the food chain damaging your health and well being
58. maximum of 6 digits there are always 3 digits to the right of the decimal point but to the left there could be 1 2 or 3 digits depending on value For example when the unit is MO and depending on the device being measured the display might show 1 123 10 123 MO or even 100 123 Page 38 Operation A summary of measurement units scientific and engineering and their symbols 1 given in Table 2 2 Table 2 2 Measurement Unit Prefixes Multiple Scientific Engineering Symbol 1000000000000000 1015 Peta P 1000000000000 1012 Tera T 1000000000 109 Giga G 1000000 106 Mega M 1000 103 Kilo k 001 10 3 milli m 000001 10 6 micro u 000000001 10 9 nano n 000000000001 10 12 000000000000001 10 15 femto f 2 6 3 3 RS 232 Setup UO Utilities RS 232 12 24 48 96 Parity None Even Odd Data Bits 78 Stop Bits 12 Figure 2 19 RS 232 Interface Setup Allows user setup of standard RS 232 interface formats Selections include Baud Rate 12 24 48 or 96 Parity None Even or Odd Data Bits 7 or 8 Stop Bits 2 When using the RS 232 interface with a printer the IEEE 488 2 Mode must be set to Talk and the State to Disable Operation Page 39 2 6 3 4 488 2 Discontinued see 7000 23 IEEE to RS 232 Interface Adapter Setup UO Utilities IEEE 4 Mode Talk Talk Listen State Disable Enable Figure 2 20 IEEE 488 2 Interface Setup Allows user setup of IEEE 488 2 interface
59. me constant for charging a capacitor In the charge phase 15 determined by the value of the capacitor times the effective source impedance of the supply The supply resistance 1s approximately where E 1s the user specified test voltage volts and I max 15 the current limit of the 1865 instrument which 15 approximately 2mA Therefore the time constant 1 E Cx T Ro Cx seconds 2000 where Cx is in uF As an example for a 500 V test voltage Ro is approximately 250 so that the time constant for charging of a capacitor is 0 25 seconds The charge time should be set for a minimum of 10 time constants When the resistance adapters discussed paragraph 3 3 1 above are used the time constant will be increased In the example above if the 100 or 1 adapter 15 placed in series with the effective source impedance of 250 the charge time will be increased by a factor of 0 4 and 4 respectively 3 3 3 Discharge Time The time constant for discharging a capacitor the discharge phase 1s determined by the value of the capacitor times the resistance of the 1865 discharge circuit The discharge resistance 1s approximately 66 The CAUTION HIGH VOLTAGE lamp 16 turned off after the user specified discharge time If the discharge time 15 set to zero or a very short time a capacitor could remain with a charge after the indicator 1s extinguished However the discharge time 1s so short this 1s not a practical
60. nder the chosen name Flash drive 1s either not connected or defective Flash drive defective format or replace Flash drive is either not connected or defective Flash drive 1s not formatted Page 61 USB SEEK ERROR USB WRITE FAULT GENERAL FAILURE USB HANDLER PORT FAILURE HARDWARE TIMER FAILURE REBOOT INVALID CALIBRATION CODE INVALID LIMIT INTERNAL HARDWARE FAILURE REBOOT LIMIT INVALID SET TO NONE LOW BATTERY VOLTAGE MAXIMUM OF SETUPS REACHED NO CALIBRATION DATA FOUND NO IEEE 488 2 INTERFACE NO INTERLOCK SIGNAL NO PASSWORD ENTERED NO SETUP DATA FOUND NO ZERO DATA FOUND PASSWORD DID NOT MATCH Page 62 Flash drive is either not connected or defective Flash drive 1s either not connected or defective Flash drive 1s either not connected or defective I O port malfunction during power up Hardware malfunction during power up Entered calibration code 1s invalid Entered limit 1 Invalid Hardware malfunction during power up No limit 1s accepted out of range or invalid Memory backup battery low voltage setups and instrument zero could be lost Maximum number of files have been stored Calibration required refer to Paragraph 5 4 Unit does not include IEEE 488 2 Option Open interlock connection at rear panel I O Port Password entry canceled re enter Memory backup battery has been disconnected reset time and date Unit requires zeroing Refer
61. nt and minus sign Page 14 Introduction Table 1 1 Front Panel Controls and Indicators Continued Number Figure 1 1 to exit sub menu amp return to main menu silii di changes made or to exit current field menu entry as entered 8 START JjQGreenPushButtn To initiate the measurement w as seh E Os Switch 1 ON 0 OFF measurement results on a flash drive voltage at the output terminals I preset limit 12a FAIL Red LED When lit in Resistance Mode the measured value 1s below the set minimum value resistance limit When lit in Current Mode the measured value 1s above the set maximum value current limit 12b PASS Green LED When lit in Resistance Mode the measured value is above the set minimum value resistance limit When lit in Current Mode the measured value is below the set maximum value current limit 13 Caution High Voltage Red LED When lit indicates presence of High Voltage at the output terminals Introduction Page 15 1 3 2 Rear Panel Controls and Connectors Figure 1 2 illustrates the controls and connectors on the rear panel of the 1865 Megohmmeter IR Tester Table 1 2 identifies them with description and function CAUTION FOR CONTINUED ERE SERVICEABLE PARTS PROTECTION AGAINST FIRE PREVENT ELECTRICAL SHOCK HAZARD REPLACE ONLY DO NOT OPEN COVERS EE EM TO QUALIFIED PERSON RATING OF FUSE FUSE
62. on to the annual battery replacement and calibration discussed below periodic cleaning of dust from the 3 1 3 disk drive when this option 1 present 1s recommended depending on the environmental conditions Vacuuming of the drive by qualified service personnel should be done in accordance with common procedures used in computer maintenance Service amp Calibration Page 77 5 2 Calibration 5 2 1 General Calibration of the 1865 Megohmmeter should be verified for performance at a calibration interval of twelve 12 months This procedure may be carried out by the user if a calibration capability 1s available by IET Labs or by a certified calibration laboratory If the user should choose to perform this procedure then the considerations below should be observed Requirements for Recalibration Temperature stabilized room at 23 degrees C 73 4 F Precision Digital Voltmeter 0 01 accuracy with calibration traceable to NIST 1 MQ standard resistor of known value within 0 01 at 100V for direct connection to 1865 input terminals traceable to SI 5 2 2 Calibration Procedure The step by step instructions for this procedure are shown on the instrument display and discussed below 1 First set time and date by selecting SET TIME DATE on the Utilities menu 2 Select CALIBRATION on the Utilities menu Once ENTER Is selected the calibration code of 1 8 6 5 2 2 5 must be entered to continue This code 15 to prevent unauth
63. orized personnel from effecting the instrument calibration The code might want to be blanked out in this manual After the calibration code 15 entered the stored reference voltage is displayed and can either be accepted or measured and re entered as instructed Page 78 Service amp Calibration If the selection 1s N no measure the reference voltage as instructed between TP6 and TP8 ground on the analog instrument board and enter the measured value To access these points it 1s necessary to remove the top cover refer to Figure 5 1 Once this voltage value 1s entered and ENTER pressed the High Voltage 100V will be turned on immediately If Y yes 1s selected the High Voltage 100V will be turned on immediately 3 Proceed to measure the voltages 1n each case as instructed enter the values and press ENTER to continue each time Two measurements will be made at levels of 100 and 1000V and one at 10V 4 Short the input and terminals to the instrument as instructed and press START 5 Enter the precise known value of the 1 standard again press ENTER 6 Remove the short and connect the standard between the and terminals 7 When START 1 pressed a calibration measurement 15 made on the standard which takes approximately 25 seconds 8 Once the standard is removed and START pressed again RANGE CALIBRATION 1 performed which takes approximately 45 seconds 9 Press START HIGH VOLTAGE IS STILL A
64. ors in range setting and ensure specified instrument accuracy the 1865 unit should generally be left in AUTO There may be an exception to this when repetitive measurements are to be made on a known range and there 1s a desire to reduce test time by eliminating range switching When auto ranging is selected the 1865 instrument will always begin the measurement phase on the highest current range 1 mA and progress down depending on the current to the device under test If the current reaches 1096 or less of the maximum for a given range the next lowest range will be switched in If a range has been selected and the current exceeds 115 of the maximum for that range the unit will indicate OVER RANGE on the display One needs to keep in mind that an over range indication does not necessarily mean that the incorrect range has been selected the device under test could also be defective Over range should not be confused with an OVERLOAD display Overload occurs anytime current to a device attempts to exceed 2mA this would generally mean a shorted or very low resistance device Page 32 Operation Table 2 1 Range Current Rape Maximum Current Example When measuring an unknown of 200 MQ at 100 V Ohm s Law tells us that the device under test would draw 0 5 uA I 100 V 200 Based on the above one would expect the 1865 instrument to auto range from the mA to 1 range 50 of maximum current or that the user should select the luA
65. ot apply an external source in excess of 5 V with jumpers JP2 JP3 or JP4 in place otherwise the instrument may be damaged These jumpers are discussed below and on some instruments physically located under the stack on the I O board Operation Page 51 Table 2 3 NOTES input signal 15 active low and requires a positive voltage external circuit which must pull the signal line down below 0 4 V but not less than 0 0 V 1 not negative The logic low current 15 0 4 mA max For the inactive state logic high the external circuit must pull the signal line above 2 5 V but not above 5 V This can be converted to a isolated active low input by removing jumper JP3 on the I O PCB Outputs can be active low optically isolated open collector drivers that pull each signal line to IGND Isolated common when asserted All outputs require a positive 5 V to 24V external source referenced to IGND and pull up resistor to operate as fully isolated signals IGND can be Isolated from system GND by removing jumper JP2 on the PCB With jumper JP2 in place optical 1solation 1s defeated allowing the outputs to be pulled up to the system 5 V with external resistors The outputs can sink up to 80 mA of current Greater currents can damage the instrument Pin 34 is connected to the input of the optical isolator through a 620 Q current limiting resistor Pin 35 1s connected to the side of the optical 1solator Recommended force
66. ows resetting of time and date into unit memory This is used as the basis for the elapsed time counter and stored calibration date T time 15 entered HOURS up to 2 digits 0 through 23 MINUTES up to 2 digits 0 through 59 SECONDS up to 2 digits 0 through 59 D date is entered In MONTHS up to 2 digits 1 through 12 DAYS up to 2 digits 1 through 31 YEARS 4 digits 1991 through 2100 Page 48 Operation 2 6 4 7 Elapsed Time When selected indicates the total elapsed time hours that the unit has been powered up This 15 from the moment of initial use and will show some time when shipped from the factory THE TOTAL OPERATING TIME FOR THIS INSTRUMENT IS 1205 50 hours HIT lt MENU gt KEY TO CONTINUE Figure 2 29 Display of Elapsed Time 2 6 4 8 Calibration Date When selected indicates date the unit was last calibrated This date is retained in instrument memory until the unit is re calibrated and then it 15 updated THISINSTRUMENT WAS CALIBRATED ON 01 14 1992 AT 11 25 45 HIT lt MENU gt KEY TO CONTINUE Figure 2 30 Display of Calibration Date Operation Page 49 2 6 4 9 Set Contrast Allows adjustment of contrast on the LCD display Use Up arrow to Increase contrast or Down arrow to decrease When the instrument is powered up it returns to the last set contrast not some nominal level D HIT ARROW KEYS TO CHANGE THE DISPLAY CONTRAST HIT lt ENTER gt KEY TO ACC
67. pproach maximum insulation resistance readings thus specifications usually require that readings be taken after a specified time again electrification time A routine test that has been widely adopted for insulation testing calls for the measurement of the apparent leakage resistance after a test voltage has been applied for 1 to 2 minutes For discussion on insulation resistance measurement methods and procedures refer to MIL STD 202 and ASTM American Society for Testing and Materials Standard D257 Applications Page 65 3 2 Test Sample Resistivity Measurements The 1865 can be used for measuring the resistivity of test samples as described by ASTM Standard D 257 which describes in detail the techniques for both surface and volume resistivity measurements The 1865 11 Test Cell is shown in Figure 3 1 Front 1865 1865 DISPLAY SELECT Megohmmeter MEGOHMMETER RESISTANCE WARNING HIGH VOLTAGE 2 Rear 1865 11 d EL Test 755 Fixture i 1865 11 Surface Plate Sample Test Inside Fixture d 1 Max Sample Thickness 8mm es Fixture Max Sample Size 100mm x 100mm Top Outer Ring Electrode u i Electrode 80mm gt Inner Ring Electrode 70mm Bottom Electrode 50mm
68. printer Results format is the same as results to USB refer to paragraph 2 6 3 6 RS 232 RS 232 must be selected on I O Menus and format set IEEE must also be selected for Talk mode and Disable state IEEE IEEE must be selected on I O Menus and set for Address Talk mode and Enable state Page 60 Operation 2 8 Error Messages BAD DRIVE REQUEST STRUCTURE BAD VOLTAGE SENT TO FUNCTION BAD ZERO CALIBRATION CALIBRATION STANDARD OUT OF RANGE CORRUPT SETUP DATA CRC ERROR ON USB PROTECT ERROR ELAPSED TIME ERROR SET TO 0 FAILURE SEE DOCUMENTATION FILE ACCESS VIOLATION FILE EXISTS USB DRIVE NOT READY USB MEDIA DEFECT USB READ FAULT USB SECTOR UNFORMATTED Operation Flash drive 1s either not connected or defective Improper voltage entered during calibration procedure Zeroing error repeat and or remove component from input terminals fixture Refer to Note on p 63 Entered value gt than 1 of 1 Megohm Stored setups lost or corrupt battery for non volatile memory may be defective or has been disconnected Stored setup lost or corrupt cyclic redundancy check Flash drive 1s write protected Elapsed time 1s incorrect and has been set to zero battery for non volatile memory may be defective or has been disconnected Hardware or software failure 1 99 list not included this manual File selected from flash drive 1s Read Only File already exists u
69. probe directly Touch only the insulated parts of the lead s 4 Never touch the test leads test fixture or DUT in any manner this includes insulation on all wires and clips when the high voltage 15 applied and the red CAUTION HIGH VOLTAGE LED is lit 5 Before turning on the 1865 unit make sure the AC power cord 15 plugged into the proper voltage source and that there is no device DUT or fixture connected to the test leads 6 After each test press the STOP red button for safety This terminates the high voltage being applied to the output terminals 7 When the CAUTION HIGH VOLTAGE LED 15 lit NEVER touch the device under test the lead wires or the output terminals 8 Before touching the test lead wires or output terminals make sure a The red STOP button has been pressed b The CAUTION HIGH VOLTAGE LED 1 OFF c The output voltage display is 0 zero 9 In the case of an emergency turn OFF the POWER switch using a hot stick and disconnect the ac power cord from the wall DO NOT TOUCH THE 1865 INSTRUMENT Position the equipment so it is easy to disconnect Disconnect by means of the power plug or power connector 10 If the CAUTION HIGH VOLTAGE LED does not go off when the STOP button is pressed immediately stop using the tester It is possible that the output voltage 15 still being delivered regardless of the TEST ON OFF control signal 11 When the 1865 instrument is used in remote control mode be extreme
70. resistance 10 but the risk of danger is greater due to the higher current being applied and the voltage resulting from the resistance This method of high resistance measurement greater than a gigohm can be very costly when it comes to equipment Ohm s Law for resistance again applies here The measurement accuracy of both methods is affected by the surrounding electromagnetic environment radiation When measuring high resistance charging of the insulation 1s required to offset radiation effects This occurs naturally when an object with a high concentration of electrons is moved near an object with no or a diminutive amount of electrons or vise versa Any slight electron change can result in noisy readings or wrong readings One method to avoid noise 15 to use a Guard Shield or Insulation 6 1 3 Surface Resistivity surface Resistance also known as sheet resistance 1s defined as the electrical resistance between two points or electrodes on one side of a material This resistance 1s calculated using the simplified version of Ohm s law Rs V Is where Rs Surface Resistance Is Surface Current V Applied Voltage Page 82 Optional Accessories Surface Resistivity is defined as the electrical resistance between two points or electrodes on one side of a material with respect to the area of a flat annulus In other words the megohmmeter reads the current that skids or travels on the surface of the material with respect to a d
71. rite the factory default settings 2 5 2 Default Measurement Conditions A set of default measurement conditions are initially established at the factory and stored in instrument memory Default conditions are those that determine the instruments status on power up thus the instrument 15 always set to a known state before any testing begins These conditions can be changed by the user for tailoring to a specific application Refer to paragraph 2 6 4 1 under Save Setup on the Utilities menu Factory default measurement conditions are Under Setup Menu Voltage 1 V Charge Dwell Measure and Discharge times 0 Mode Auto Range Auto Selected on lower level menu Limit None Stop on Pass No to Average None Under I O Menu Display Type Resistance selected on lower level menu Result Format Engineering Units RS 232 Enable Handler On Under Utilities Menu Lockout Off Backlight On Operation Page 25 2 5 3 Automatic Measurement Mode Measurements in the automatic mode can be initiated after connecting the DUT by simply pressing START Test conditions are determined by either the power up default conditions or by recalling a previously stored setup from instrument memory In either case a test cycle 1s sequenced automatically Figure 2 5 once START 1 pressed and results displayed Figure 2 6 When a test limit 15 entered a PASS FAIL indication can be displayed in place of the actual measured va
72. selection from two different modes of operation Auto or Manual measurement In Auto the user presses START to initiate the entire test cycle automatically The first phase of the cycle 15 charge time during which the device initially charges up to the applied test voltage The second phase 1s dwell or time of electrification during which the device 1s fully charged but prior to a measurement The third phase 1s measure time during which measured results are displayed The fourth and last phase 15 discharge time during which the voltage 1s removed and the device allowed to discharge In Manual test cycle timing 1s under complete user control START must be pressed to initiate the charge and measure phase and STOP pressed to discharge the device Operation Page 31 2 6 2 7 Range Utilities lt gt Figure 2 13 Range Selection A lower level menu accessed by pressing ENTER allows the selection of Auto or one of seven different measurement ranges 1 mA through 1 nA which is the maximum current for the selected range In auto mode the 1865 instrument will automatically select the optimum range depending on the programmed test voltage and current drawn by the test device Any choice other than Auto 1 mA through 1 nA range 15 at the users discretion Determination of the range Is governed by the maximum current available to the for that measurement range and 1 listed in Table 2 1 To eliminate operator err
73. sponds to the test instrument 1 1865 11 Test Cell 2 1689 7003 00 BNC adapter 1689 7003 00 Figure 6 1 Rear View of 1865 11 Test Cell Make connections carefully as illustrated m Figure 6 2 It 1s important to follow these directions exactly to avoid improper measuring techniques and damage to the test fixture Proper knowledge of material and fixture allows the DUT to be measured accurately while taking into account correct polarity To connect the fixture to an 1865 Megohmmeter First remove any DUT Cables from the 1865 instrument and 1865 11 fixture Carefully insert the 1865 11 BNC Male into the 1689 7003 00 adapter Insert the adapter into the banana jack on the 1865 instrument Insert its pigtail banana plug into the GUARD banana jack on the 1865 instrument Page 80 Optional Accessories 5 Insert the 1865 11 banana plug into the banana Jack labeled on the 1865 instrument 6 Foraccurate measurements perform a zero each time the voltage 1s changed and each time the Rs Rv switch setting on the fixture 15 changed Refer to Figure 2 Figure 2 illustrates the connection of the 1865 11 Test Cell to an 1865 Megohmmeter Frant 1865 Quad Tech d Pm Megohmmeter 265 Dum AE z a E i See 2 620M0 NETA ESI 1865 11 Surface Plate Sample Test Fixture Inside 1865 11 a o Max Sample Thi
74. sting Insulation resistance of materials 1s one of several parameters that may indicate the condition of insulation An insulation test 15 to measure the resistance offered by the insulating members of a component part to an impressed direct voltage tending to produce a leakage of current through or on the surface of these members There are times when knowledge of insulation resistance can be very important for example when resistance 15 high it may be the limiting factor in design of a high impedance circuit when resistance is low it can disturb the operation of circuits intended to be isolated Insulation resistance measurements should not be considered the equivalent of a voltage breakdown test Material with high insulation resistance could possess a mechanical fault that might fail during a voltage test and conversely material with low insulation resistance might not breakdown during a voltage test Factors that affect insulation resistance measurements include such things as temperature humidity previous conditioning test voltage charging current and duration of the test voltage electrification time It 1s characteristic of certain components for example capacitors or capacitive components or materials for the current to fall from an instantaneous high value to a steady lower value consequently the measured insulation resistance will increase from an appreciable time as test voltage 1s applied Because of this it may take minutes to a
75. t Increasing the quantity of setups results In a slower retrieval process To save set of test conditions externally select USB from the menu in Figure 2 24 You can save a new setup or overwrite an existing one on the flash drive Pressing CNCL returns the menu to the setups stored in internal memory Figure 2 22 2 6 4 2 Recall Setup Figure 2 25 Setup Test Conditions Allows a previously stored set of test conditions to be recalled from Instrument memory Test conditions are those that are user programmable the Setup and I O menus and saved as discussed above To recall a set of test conditions one needs to arrow down or up to the desired set DEFAULT 15 always one of the set of test conditions that can be recalled as discussed in the previous paragraph Selecting USB allows setups to be recalled from a flash drive if one is connected Selecting del will delete a set of test conditions and requires a Yes or No confirmation Operation Page 45 When there are more setups than can fit on the display the page down key 15 active If there 1s less than a whole page below the display wraps around to the previous display Continuing to page down will eventually return to the first display of setups 2 6 4 3 Zero The zeroing process automatically measures stray parameters and retains the data It 1s used to correct measurements so that results represent parameters of the DUT alone without test lead or fi
76. tage source so to improve measurement accuracy and eliminate applied voltage dependency an extra current measurement based on another set of reference standards Rb Ra 15 made This measurement results can be expressed as E2 Rb Ra Ex The ratio of the E2 El results the expression for the unknown Rx Ra Rb Rs E2 E1 Rx A D Figure 4 1 Detector Block Diagram Page 72 Theory Power Supply Assembly The 1865 Power Supply Assembly consists of two modular switching power supplies The first has 24 5 and 12 Vdc output It supplies the Instrument Board second has 5 and 15 Vdc outputs and powers the and Processor boards USB Port A USB port 15 included on the 1865 for storing multiple setup conditions beyond what can be retained in the internal RAM of the unit and for storing test results It is also used for loading program software 4 2 3 Instrument Options IEEE 488 2 Board amp Cable Discontinued The IEEE 488 2 board 16 offered as an option to the 1865 and allows complete control over all aspects of the instrument Any user control available through the keyboard or any information available for display can be accessed over this interface This board 15 mounted towards the right rear of the unit stacked above the processor board Connection to the IEEE 488 2 connector on the rear panel 1 made by an interconnecting cab
77. the current time and date as instructed on the display refer to paragraph 2 6 4 6 1f necessary After the time and date have been reset press MENU to return to the menu display Press Up or Down Arrow key to select Zero Press ENTER key to activate the Zero routine and follow instructions on the instrument display Once the Time and Date have been reset and the instrument zeroed the 1865 15 ready for routine measurements It s important to note that the elapsed time will have been reset back to zero during this process Service amp Calibration 5 1 3 Loss of Display Contrast If for some reason the Instrument should loose its display contrast it is possible to reset it easily using the procedure below Loss of contrast would exhibit no display at all when the instrument is powered up Procedure for restoring loss of contrast Consider the SELECT buttons as labeled 1 2 3 and 4 from top to bottom Turn the instrument on and wait 20 seconds or after High Voltage light flashes Press MENU key twice Press SELECT 4 one time Press SELECT 1 two times Press ENTER Press SELECT 1 many times till contrast returns to normal Press ENTER Arrow up to SAVE SETUP and save as DEFAULT PEN aS If the above procedure fails to restore the contrast try repeating again Failing restoration of the contrast may be indication of another instrument problem 5 1 4 Preventive Maintenance Cleaning In additi
78. ts that can be connected very close to the 1865 input terminals rather than through the lead set provided Unknown Unknown Unknown and Unknown connected to DUT GUARD shorted to GND optional Figure 2 2 Two Wire Ungrounded Connection The two wire grounded measurement is a common type of connection to be used on the 1865 This 1s the recommended connection on grounded components or components that are some physical distance from the input terminals of the unit A grounded component is one in which one of its connections goes to an earth ground whereas on an ungrounded component neither connection goes to earth ground component being measured with a lead set is considered to be a physical distance away from the terminals and thus the two wire grounded connection is often recommended Unknown Unknown Unknown and Unknown connected to DUT Unknown connected to GND Figure 2 3 Two Wire Grounded Connection Operation Page 23 A three wire guarded connection is necessary to measure resistance between two points in the presence of resistance from each of these points to a third point Refer to paragraph 3 6 for a discussion of guarded measurements The guarded measurement may require different grounding techniques depending on the expected impedance of the DUT a DUT Grounded b DUT Ungrounded Unknown and Unknown are connected to DUT GUARD to DUT Guard Point Unknown shorted to GND OR GUARD shorted
79. u u a Ba co ena 17 143 Power 17 DAA Satoty InSDOOCLHIOU 19 Operation Section 2 2 1 Terms and OV CHOU Ss Lu LIS ua Foe 21 2 7 e EE 2 2 3 ZETO pM 22 2 4 Connection to Device Under Testi uuu r u u uuu uu 2 1021 eene eene 22 2 5 Measurement Procede otio 24 24 2 5 2 Default Measurement Condltions 25 2 5 3 Automatic Measurement Mode 26 2 5 4 Manual Measurement Mod lt e 28 2 6 lotil ir diede 28 28 2 0 2 SCUID MIU 29 PX UNAM RA 29 30 30 240 0 Measure 30 20 2 5 Discharge 31 u 31 CI Rm 32 S Lillium usnu M 35 2 0 0S 0 08 ON B OS 36 2 0 2 T0 FAO DV CLASS
80. und Data set ready Data terminal ready db9 to db25 Cable Configuration 1865 Pin Function Receive data Connect Transmit data Transmit data to Receive data Data terminal ready Data set ready signal ground signal ground Data set ready Data terminal ready Figure 2 34 RS 232 Cable Configurations 2 7 5 Sample Program for RS 232 OPEN com1 9600 n 8 1 rs FOR RANDOM AS 2 some com ports require this 1e 15 OPEN com2 9600 n 8 1 FOR RANDOM AS 2 others run best without rs PRINT 2 system lock 1 PRINT 2 1dn get unit identification GOSUB read serial data subroutine r INPUTS x 2 PRINT idn r PRINT 22 syst dcal get calibration date GOSUB cget r INPUTS x 2 PRINT calibration date is r PRINT 2 conf fres s configure unit PRINT 2 conf tch 0 PRINT 72 conf tme 0 PRINT 2 conf volt 100 FOR 1 7 1 TO 30000 NEXT 1 delay 55 PRINT 2 meas res Operation Page 59 FOR 1 1 TO 30000 NEXT 1 PRINT 2 fetc GOSUB cget s INPUTS x 2 PRINT res at 100 volts is s PRINT 2 system lock 0 END cget subroutine to get serial input loop until first character 1s received DO WHILE LOC 2 0 LOOP then get the rest of the string y x LOC 2 DO WHILE x y y x FOR jJ 1 TO 300 NEXT J x LOC 2 LOOP RETURN 2 7 6 Results to Printer The 1865 can be setup to output to an RS 232 or IEEE
81. urement If the Fetch is sent before data Is displayed a timeout can occur which will cause the 1865 to stop responding to RS232 commands and the 1865 would have to be reset manually RANGe Set the range to Auto 1mA 100uA 10uA 100nA InA set to average 000 LIMIt value Set the limit to value floating point number FRESult Set the result format to S Scientific E Engineering DISPlay type Set display type to R Resistance I Current P Pass Fail N No Display SONPass Stop on pass 000 RVALId Is results filename valid XXXXXXXX RTOUSB Results to USB Table 2 5 IEEE and RS 232 Commands Continued Operation Page 53 Command Function Parameter s DUPLicate Save results as duplicate filename on USB xxxxxxxx NEW Save results as new filename on USB XXXXXXXX APPend Append results to existing filename XXXXXXXX CLOSe Close results of filename XXXXXXXX SYSTem TIME Set the time to hours minutes hh mm DATE Set the date to month day year mm dd yyyy LOCKout state Set the front panel lockout off or on 0 Off 1 On ELAPsed Query the elapsed time the machine has run DCALibration Query the calibration date MEASure RESistance Measure the resistance value CURRent Measure the current value FETCh Fetches the most recent measurement value with pass fail 1f limit selected for the selected parameter resistance or current The character sequence is as follows terminated with a line feed N
82. uring the zeroing process corrections are calculated and stored in instrument memory and applied to ongoing measurements Generally the unit should be zeroed at least once per day and each time test leads or fixtures are changed The zeroing routine 1s accessed through the Utilities Menu by selecting ZERO instructions are given on the LCD display Refer to paragraph 2 6 4 3 2 4 Connection to Device Under Test Figure 2 1 illustrates the front panel input terminals and a basic block diagram of their function Figure 2 1 Input Panel and Block Diagram An optional shielded lead set 1s available for use with the 1865 unit Part Number 1865 5 How the connection to the DUT is made depends on the unknown being measured if it is a grounded ungrounded or guarded device 1865 instrument is supplied with two resistor adapters which are recommended for use only when measuring high value low leakage capacitors These are to be added in series with the terminal lead to eliminate fluctuating test results when measuring this type of device Refer to paragraph 3 3 CAUTION DO NOT GROUND the negative unknown terminal This will result in invalid measurements Page 22 Operation Figures 2 2 through 2 4 illustrate various methods of connection to the device under test DUT Figure 2 2 illustrates the two wire connection to DUT The two wire ungrounded connection 15 the recommended connection of ungrounded components or componen
83. xture capacitance Zeroing 1 recommended at the start of each work day or more often if leads fixture or test configuration to DUT 15 changed Zeroing should also be performed anytime the test voltage Is changed which also includes recalling a set of test conditions from memory with a different test voltage It 1s important to note that anytime the instrument 15 zeroed it 1s done at the test voltage currently specified When Zero 15 selected the menu screen and the Enter key 15 pressed you are prompted by instructions on the display the first of which is shown in Figure 2 26 ZERO 500 VOLTS REMOVE ALL COMPONENTS FROM THE TEST FIKTURE HIT START WHEN READY HIT lt CNCL gt TO EXIT Figure 2 26 Zeroing Procedure Once the zeroing is initiated by pressing START the next message displayed 15 ZERO CAL IN PROGRESS Once complete typically a minute or slightly longer the next message displayed 1s COMPLETE HIT lt MENU gt KEY TO CONTINUE Page 46 Operation 2 6 4 4 Lock Out Allows user to turn the keypad lock feature ON or OFF There are two choices which can be selected lockout only and lockout with setup recall In both modes only the START STOP and MENU on the instrument front panel are active all other keys are disabled The difference is that in lockout with setup recall the menu key also allows setups to be recalled from instrument memory When either 15 selected the operator must

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