HI-4456 - ETS
Contents
1. Table 5 2 Optional Parts List Part Description Optional Parts Probe Support HI 4456 490984 Tripod Dielectric 4456 491000 Fiber Optic RS232 Interface HI 4413G Archived 4 2 10 HI 4456 Manual Page 15 6 0 THEORY OF OPERATION Introduction This section discusses the theory of operation and the functions of the HI 4456 Isotropic Electric Field Probe A high level block diagram Figure 6 1 is included to aid the discussion The objective is to provide information that enhances user understanding of the design of this probe System Theory The HI 4456 Broadband Isotropic Electric Field Probe uses three orthogonal thermal sensing elements Each of the elements responds to the electric field component aligned with the particular element The output of each element is proportional to the RMS value of the field component The output of the three elements are summed as vector quantities and an output proportional to the resultant field generated A microprocessor is contained in the instrumentation housing located at the base of the probe shaft The microprocessor generates an output corrected variations in the sensor using lookup tables located in the processor memory The resultant value is transmitted in an ASCII digital format through the optical cable to the readout The probe s self contained power supply employs a 3 6 VDC NiCd battery which provides up to 17 hours of continuous operat2. 20 C to 65 C 4 F to 140 F operating the probe in extreme temperatures will reduce operating time significantly The optimum operating temperature range for these batteries is 20 to 30 C 68 F to 86 F The battery in the 4456 probe does not require periodic deep discharges to reverse the capacity depleting memory effect caused by repeated shallow discharges however undercharging can reduce battery capacity Therefore after the charging procedure is complete be sure that the battery is fully charged before resuming field operation If the battery exhibits low terminal voltage during charging or if it appears unable to acquire or maintain an appreciable charge individual cells in the battery may be shorted or damaged f for any reason your battery needs replacement contact Holaday Customer Service for assistance Archived 4 2 10 HI 4456 Manual Page 11 5 0 MAINTENANCE Introduction This section explains which maintenance tasks can be performed by the user It also provides information regarding replacement and optional parts If you have any questions concerning probe maintenance consult Holaday Customer Service Maintenance Recommendations Maintenance of the HI 4456 probe is limited to external components such as cables or connectors Any calibration or maintenance task which requires probe disassembly should be performed at the factory Check with Holaday Customer S
3. The cables are color coded white for XMIT yellow for RCV Identically colored dots are located on the electronics housing adjacent to these connectors Be sure that each cable is attached to the proper probe connector 8 9 6 0 gt XMIT RECV ARM Q XO OFF Figure 3 1 Switch and Connectors When the fiber optic cables are not attached always cover the probe connectors with the protective plastic covers supplied with the unit or with similar material This prevents dirt or other contaminants from entering the connector and causing communication problems The ARM OFF switch activates deactivates the probe In the ARM position the probe is powered by its internal 3 6 VDC NiCd battery in the OFF position the probe is inactive To prolong battery life set the ARM OFF switch to OFF at the end of a test sequence or when the probe is not in use Archived 4 2 10 HI 4456 Manual Page 7 CHARGER standard fast charger is supplied with the HI 4456 When charging is complete the fast charger acts as a trickle charger The battery can be left on this maintenance mode indefinitely and it s performance will not degrade Battery The NiCd battery provides up to 17 hours of probe operation when fully charged Archived 4 2 10 Page 8 4456 Manual Archived 4 2 10 HI 4456 Manual Page 9 4 0 BATTERY CHARGING Introduction Each HI 4
4. subject to misuse neglect accident unauthorized service or abnormal conditions of operation In the event an instrument covered by this warranty fails Holaday Industries Inc will without charge repair and recalibrate the instrument if returned to their factory within one year of the original purchase provided that Holaday Industries examination discloses to its satisfaction that the product is defective Holaday Industries Inc may at its option replace the product in lieu of repair If the defect was caused by misuse neglect accident unauthorized service or abnormal conditions of operation repairs will be billed at a nominal cost In such cases an estimate will be provided before work is started if requested by the purchaser For warranty service contact Holaday Industries Inc Provide the serial number of the instrument and complete details regarding the failure mode You will then be given either service information or shipping instructions Return the instrument to the factory transportation prepaid Repairs will be made at the factory and the instrument will be returned to you transportation prepaid Holaday Industries Inc assumes no responsibility for loss of or damage to products in transit Warning EXTREME CAUTION IS ADVISED WHEN WORKING IN ENVIRONMENTS WHERE HIGH INTENSITY ELECTROMAGNETIC FIELDS MAY EXIST AND WHERE CONTACT WITH HIGH VOLTAGE OR HIGH CURRENT CIRCUITS OR APPARATUS IS POSSIBLE ACCIDENTAL
5. 456 probe contains a rechargeable nickel cadmium NiCd battery A fully charged battery nominal output voltage of 3 6 VDC provides up to 17 hours of continuous operation NOTE Holaday Industries Inc charges the internal NiCd battery of the HI 4456 at the factory in order to calibrate the probe prior to shipment While every effort is made to ensure that your probe arrives ready to use we cannot guarantee that this will be the case Always check the condition of the probe s battery prior to making any measurements To check probe battery voltage refer to the operation of the BAT keypad in Section 8 0 of the HI 4416 User s Manual Charging Procedure Step 1 Plug the charger into a suitable AC source Step 2 Set the probe switch to OFF Insert the plug on the charger cable into the probe s CHARGER jack Step 3 The battery is now charging This may take approximately 1 hour depending on how deeply the batteries are discharged When charging is complete the charger automatically goes into a trickle charge and will continue to do so until the probe is disconnected Archived 4 2 10 Page 10 4456 Manual Battery Tips NiCd batteries have several characteristics that can affect both their performance and operating life The following tips advise you how to take advantage of these characteristics to get the most out of your probe s battery Although NiCd batteries are rated for operation in temperatures from
6. Archived 4 2 10 4456 Isotropic Electric Field Probe User s Manual Declaration of Conformity We HOLADAY INDUSTRIES INC 14825 MARTIN DRIVE EDEN PRAIRIE MN 55344 USA declare in our own responsibility that the HOLADAY product described in this instruction manual is in compliance with EN EMC Directive 89 336 EEC EN50082 1 EN55011 President HOLADAY INDUSTRIES INC Copyright 9 1999 by Holaday Industries Inc Manual 600075 2 00 12 50 Archived 4 2 10 Revision Record Manual 600075 HI 4456 Isotropic Electric Field Probe Revision Description Date Release 8 97 A Added CE Label 10 97 B Revised 1 98 C Changed Charger Specs 8 99 D Changed Area Code 2 00 Archived 4 2 10 1 0 2 0 3 0 4 0 5 0 6 0 TABLE OF CONTENTS DESCRIPTION 1 Introduction 1 HI 4456 SPECIFICATIONS 3 ACCEPTANCE AND CONTROLS 5 Introduction 5 Unpacking and Acceptance 5 RODE co 5 XMIT RCV 5 ARM OFF 6 CHARGER x aor 6 Battery suus oy gu Edu So wei tue 7 BATTERY CHARGING 9 Introduction 9 Charging Procedure 9 Pantay Ie ERI TUE 10 MAINTENANCE 11 Introd ctiOn i e Bea 11 Maintenance Reco
7. CONTACT WITH OBJECTS OR CIRCUITS OPERATING AT HIGH VOLTAGES OR HIGH CURRENTS CAN BE LETHAL HOLADAY INDUSTRIES INC ASSUMES NO LIABILITY FOR ANY DAMAGES OR PERSONAL INJURY WHICH MAY RESULT FROM Archived 4 2 10 HI 4456 Manual Page 1 1 0 DESCRIPTION Introduction The HI 4456 RF Electric Field probe is a broadband isotropic sensor suitable for a wide range of RF microwave measurements While the HI 4456 is suited for many types of measurements within its frequency range it is primarily designed for measuring pulsed fields such as are found in radar applications The thermal sensor elements respond accurately to a wide range of signal waveforms providing a true RMS representation of the field waveform Applications include health and safety monitoring radar transmitting antennas and measuring any type of RF pulsed radiation The HI 4456 probe is optically isolated to minimize field perturbation during measurements The HI 4456 probe assembly consists of a spherical casing containing the sensor which is mounted on one end of a shaft the other end of the shaft is attached to an extrusion which houses the electronics Figure 1 1 The sensor and electronics housing operate and are calibrated as a unit The HI 4456 sensor consists of three mutually orthogonal perpendicular electric field sensors The electric field components in each of these directions are summed as vectors and the resultant field value magnit
8. ervice 952 934 4920 before opening the unit to avoid problems with your probe s warranty NOTE Opening the probe enclosure may void your warranty If your system is still under warranty contact Holaday Customer Service before performing any maintenance inside the probe Upgrade Policies Periodically probes are upgraded to enhance functionality These upgrades are commonly announced through Holaday Engineering Bulletins Return Procedures To return a probe to Holaday use the following procedures Step 1 Briefly describe the problem in writing Give Archived 4 2 10 Page 12 4456 Manual details regarding the observed symptom s and whether the problem is constant or intermittent in nature If you have talked previously to Holaday Customer Service about the problem provide the date s the name of the service representative you spoke with and the nature of the conversation Include the serial number of the item being returned Step 2 sensor and electronics housing are engineered to operate as a unit and MUST be returned together Carefully package the probe assembly in the carrying case Use the original boxes and packing materials if possible If not use the Parts List in Table 5 1 to order new boxes and foam packing from Holaday Industries Inc NOTE If your probe is calibrated in accordance with MIL Std 45662A it is greatly to your benefit to retain the original shipping box and packing
9. g electronics housing 419 mm 16 5 in Probe diameter 76 mm 3 0 in Weight 0 54 Kg 19 oz Optional Equipment See Table 5 2 Archived 4 2 10 HI 4456 Manual Page 5 3 0 ACCEPTANCE AND CONTROLS Introduction This section contains information on unpacking and acceptance of the 4456 probe controls probe connectors the battery and the battery charger Unpacking and Acceptance Step 1 Upon delivery of your order inspect the shipping container s for evidence of damage Record any damage on the delivery receipt before signing In case of concealed damage or loss retain the packing materials for inspection by the carrier Step 2 Remove the probe from its shipping containers Save the boxes and any protective packing materials for future use Step 3 Check all materials against the packing list to verify that the equipment received matches that which was ordered f you find any discrepancies note them and call Holaday Customer Service for further instructions Be sure that you are satisfied with the contents of your order and the condition of your equipment before installing the probe Probe A switch two fiber optic connectors and a battery charger connector are mounted on the HI 4456 electronics housing Figure 3 1 XMIT RCV The fiber optic cable assembly from the receiver is attached to the probe via two Archived 4 2 10 Page 6 HI 4456 Manual ARM OFF connectors
10. ion Refer to Appendix B for details of the ASCII output formats For specialized applications you may use a computer with an RS 232 serial port to communicate directly with the HI 4456 using the optional HI 4413G RS 232 interface Archived 4 2 10 HI 4456 Manual 16 Page HOVE 84398VHO I1OJINOO 43MOd AlddnS SNIHOLIMS SOILdO 43814 AY3LLV8 440 HOLIMS H3MOd 578 lOMINOO U3L43ANOD a v 135330 QNV JONVY 318v19313S WO3d33 NOILVLNAWNYLSN 1 6 igure F Probe Block Diagram Archived 4 2 10 HI 4456 Manual Page 17 Probe Operation Receiver commands to the probe consist of the following Send reading Read battery voltage Zero Set sleep timer Switch range Read temperature Enable axis The signal flow within the probe is shown in the block diagram To measure field strength three mutually orthogonal dipole antennas one per axis are used to provide an isotropic response to the ambient field The signal from each axis is fed to a Schottky diode detector operating in its Square Law region After filtering the signals generated by each axis are added vectorially the resultant is fed to the instrumentation amplifier whose output feeds the selectable range offset stage NOTE The HI 4456 does not allow the option of measuring on an individual axis all three axes are active at all times Consequently the axis keypad
11. materials One of the criteria for certifying a calibration to MIL standards requires Holaday Industries to always ship equipment in the specified packaging When a MIL Standard instrument is sent to Holaday in other packaging we must replace it with the specified packaging materials for return shipment YOU WILL BE BILLED FOR THE NEW PACKAGING If the probe is under warranty refer to the Limited Warranty at the front of this manual for additional information about your return Periodic Preventive Maintenance The 4456 probe assembly sensor and electronics Archived 4 2 10 HI 4456 Manual Page 13 housing require an annual calibration check to verify that they are performing within specifications This calibration check may be performed at the factory by Holaday Service Personnel Return your probe s using the original packing materials if possible to Holaday Industries Inc Attn Service Department 14825 Martin Drive Eden Prairie MN USA 55344 Parts Information Use the following tables for ordering replacement Table 5 1 or optional Table 5 2 parts for HI 4456 probes Table 5 1 Replacement Parts List Part Description Replacement Part Number Parts Battery Pack 3 6 VDC 491038 Rechargeable Standard Fast Charger 115 230 491198 36 Volt Cable Fiber Optic Glass 2 Meter 490994 02 Handle Assembly 491073 HI 4456 User s Manual 600075 Archived 4 2 10 Page 14 4456 Manual
12. mmendations 11 Upgrade Policies 11 Return Procedures 11 Periodic Preventive Maintenance 12 Parts Information 13 THEORY OF OPERATION 15 Introduction scm Bee de andi avg as e 15 System Theory 15 Probe Operation 17 Probe Power Supply 18 Zeroing irs oct eae Oh See ear ona See ES 18 Archived 4 2 10 7 0 APPLICATION CONSIDERATIONS 21 Introd cti n 3 x4 n Le Ry x RET Rs 21 Out of Band Considerations 21 Resolution Limitations 21 Probe Support Structures 21 APPENDIX A ERROR CODES Gh Shae CLA 23 Probe Error 23 APPENDIX B HI 4456 OPERATING PROTOCOLS 25 Introduction 25 Communication Protocol 2b Information Transfer Protocol 2b Command Structure 25 Commands eid ee Gy TER 26 Probe OUTPUL saleak ae wie Sd RARE IS 28 Archived 4 2 10 Limited Warranty Holaday Industries Inc warrants each model HI 4456 Isotropic Electric Field Probe to be free from defects in material and workmanship for a period of one year from the date of shipment to the purchaser This warranty extends to the original purchaser only and does not apply to the batteries or to any products or parts
13. nd with one of the following strings These strings begin with a colon and end with a carriage return EO1 EO2 E03 E04 E05 206 Communication error e g overflow Buffer full error Too many characters contained between the Start Character Carriage Return sequence The received command is not valid The received parameter is not valid Hardware error e g EEPROM failure Parity error Archived 4 2 10 Page 24 4456 Manual Archived 4 2 10 HI 4456 Manual Page 25 APPENDIX B HI 4456 OPERATING PROTOCOLS Introduction The information in this appendix assumes that you have purchased the optional HI 4413G Fiber Optic RS232 Interface and are capable of communicating directly with the HI 4456 probe via computer No system readout is required when using this configuration Communication Protocol Data Type RS 232 Serial Data Mode Asynchronous Word Length 7 bit Parity Odd Stop Bits 1 Data Rate 9600 baud Information Transfer Protocol The HI 4456 operates as a Controller Mode device This probe only responds to commands from another device it transmits no data without first receiving instructions to do so Command Structure A command to an HI 4456 probe consists of 1 a command letter followed by 2 possible parameters 3 terminated with a carriage return When it completes the command the probe responds with a string consisting of 1 a start charac
14. s on the front panel of the HI 4416 System Readout have no effect when an HI 4456 is connected to it For each of the four ranges the selectable range and offset stage provides a coarse analog zero for the measured signal The output of the range offset stage is fed to the A D multiplexer then to the analog to digital A D converter itself After acquiring the composite three axis signal the microprocessor commands the A D multiplexer to read the battery voltage and temperature sensing lines Archived 4 2 10 Page 18 4456 Manual Data from the A D converter is fed to the microprocessor which transmits it to the receiver The EEPROM stores all calibration data for the probe Probe Power Supply The HI 4456 probe is powered by a sealed rechargeable 3 6 VDC NiCd battery which drives both the analog and digital power supplies separate power sources provide isolation between the analog and digital circuitry With the probe switch in the ARM position battery voltage is applied to the power switch which routes this voltage to the power supply enabling the microprocessor The power switch is controlled by a timer circuit The timer monitors the fiber optic connector input line to determine whether the probe has received a command during a specified period several seconds If no command is received during this period the timer signals the power switch to disable the power supply and the microprocessor In essence
15. ses must be taken into account when performing certain operations such as zeroing On the lower end the 4456 can exhibit significant response to frequencies below 300 MHz Such out of band responses may pose a problem when zeroing the unit since that operation assumes a zero field condition At the upper end similar problems may occur Resolution Limitations Limitations in probe resolution may result in a non zero reading when the receiver is zeroed If this occurs it does not necessarily mean either that there is a problem with the receiver or that your readings are inaccurate Receiver linearity is specified as O 5 dB full scale in addition the variance of the A D converter is 2 least significant bits When using the most sensitive range on a given probe these specifications create the possibility that under zero field conditions the receiver may display a non zero value Probe Support Structures It is very important to keep conductive objects away from the 4456 Any such objects in the proximity of the probe may distort the near field and compromise measurement accuracy If your application requires Archived 4 2 10 HI 4456 Manual Page 22 measurements from a fixed position always mount the probe on a non metallic platform using non metallic Screws Archived 4 2 10 HI 4456 Manual Page 23 APPENDIX A ERROR CODES Probe Error Output If an error occurs the probe will respo
16. ter 2 the command letter followed by 3 data if required and terminated with 4 a carriage Archived 4 2 10 Page 26 HI 4456 Manual return If the command does not require the probe to return any data the probe simply responds with the command letter and a carriage return If an error occurs the probe responds with an error code as detailed in Appendix A Commands Command Description B Read battery voltage Cx Set baud rate x 1 sets rate to 2400 baud x 2 sets rate to 9600 baud New baud rate does not take effect until the next power up Dx Read probe data x 1 enables short form output x 2 enables long form output Lx Load table data x ASCII hex data Rx Set range x 1 2 3 4 or N next range Sx Sleep timer x number of seconds to wait for a command before putting probe into the sleep mode Tx Read Temperature x C or F Ux Set unit type x 1 2 3 or N next unit 1 V m 2 mW cm 3 V m Archived 4 2 10 HI 4456 Manual Page 27 Vtx Null Verify table data t table same table as for Lx command above x number of bytes to send in one string Zero Send the ASCII null character This is a special command that can be used as the initial command to the probe after it is powered up The probe responds with N Archived 4 2 10 Page 28 4456 Manual Probe Output Command HI 4456 Response B D1 D2 Rx Bxx xx
17. the probe goes dormant to conserve battery power only the fiber optic input circuitry remains active in order to detect new commands When the next command from the receiver reaches the probe power is reapplied automatically and the processor is reactivated waking up the probe NOTE The probe uses volatile random access memory RAM If for any reason power to the probe is lost the probe must be re zeroed Zeroing When the receiver sends a zero command the probe must be in a zero field environment This is because the zero command causes the multiplexer via the processor to perform a normal read cycle on the composite axis signal This procedure is executed for all ranges When Archived 4 2 10 HI 4456 Manual Page 19 the processor receives all the zero field values it stores them in a special register these values are subtracted from all subsequent measurements Therefore a probe which is zeroed while it is not in a zero field environment will give erroneous readings Archived 4 2 10 Page 20 4456 Manual Archived 4 2 10 HI 4456 Manual Page 21 7 0 APPLICATION CONSIDERATIONS Introduction The following subsections contain information designed to help you maximize the effectiveness of the 4456 Out of Band Considerations Although the HI 4456 is nominally rated for operation from 300 MHz to 18 GHz it may respond to signals both above and below these frequencies Such respon
18. ude transmitted via the fiber optic cable to the receiver HI 4416 System Readout or HI 4413G RS 232 Computer Interface The frequency response of the HI 4456 extends from 300 MHz to 18 GHz Extended frequency calibration points are available up to 40 GHz The dynamic range Archived 4 2 10 Page 2 HI 4456 Manual of the probe extends from 0 3 mW cm to 265 mW cm Figure 1 1 HI 4456 Probe Archived 4 2 10 HI 4456 Manual Page 3 2 0 HI 4456 SPECIFICATIONS Dynamic Range Ranges Frequency Response Linearity Isotropicity Peak Overload Pulse Energy Density Overload Environmental Operating Temperature Humidity Fiber Optic Cable Connectors Battery 0 3 to 265 mW cm 100 300 1 000 Volts meter full scale 300 MHz to 1 GHz 0 3 dB 1 GHz to 18 GHz 1 5 dB 18 GHz to 40 GHz 0 6dB 0 5 dB full scale F S 2 least significant bits LSBs of A D converter 300 MHZ to 18 GHz 1 2 dB 18 GHz to 40 GHz 2 dB 30 W cm 150 W ysec cm 10 C to 40 C 50 F to 104 F 5 to 95 relative humidity non condensing Standard FSMA 3 6 VDC 1400 mA h rechargeable Nickel Cadmium NiCd Archived 4 2 10 Page 4 HI 4456 Manual Battery Charger 115 230 VAC approximately 1 hour Battery Life 17 Hours continuous full charge Probe Mount Ye 20 UNC tapped hole internal thread in base of probe Size Length includin
19. where xx xx is the battery voltage Dxx xxuuu the short form output is the reading The position of the decimal point depends upon the range setting of the probe uuu units V V m mW2 mW cm V2 V m underscore indicates a space character Dxx xxuuurrrobaaat the long form output XX XX the reading as described for 01 uuu units as describe 01 rrr recorder out value A 3 digit ASCII number from O to 255 over range indicator N ok over range b battery status N safe operating level W warning level fail level aaa axis enable enabled t terminating carriage return Rx where x is the range returns the range currently in use 1 2 3 4 enables the selected range N sets the probe to the next higher range Archived 4 2 10 HI 4456 Manual Page 29 TF Txxx where xxx is temperature in Fahrenheit TC Txxx where xxx is temperature in 9 Centigrade Vtx Vxx xx where xx is table data in ASCII hex Archived 4 2 10 Page 30 4456 Manual NOTES
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