Agilent Technologies 34420A Especificaciones

Chapter 3 Features and Functions (continued)Math Operations 74Null (Relative) Operation 77Reading Hold 79Triggering 80Trigger Source Choices

Chart Output (Analog Output)You can use the Chart Output (Analog Output) connector on the rearpanel to run a strip chart recorder or similar instrumen

2) To set the chart output voltage to ±3.0 V to correspond to an inputtemperature range of 5° C to 45° C with a mid temperature of 25° C(chart output

Chart RolloverTo prevent the loss of data, the chart output will "rollover" if ameasurement would cause the chart output to exceed the limit

Remote Interface Configuration This section gives information on configuring the remote interface. Forprogramming information, see Chapter 4, “Remote

HP-IB Address Each device on the HP-IB (IEEE-488) interface must have a uniqueaddress. You can set the meter’s address to any value between 0 and 31.

Baud Rate Selection (RS-232) You can select one of six baud rates for RS-232 operation. The rate is setto 9600 baud when the meter is shipped from th

Parity Selection (RS-232) You can select the parity for RS-232 operation. The meter is configured foreven parity with 7 data bits when shipped from

Programming Language SelectionYou can select one of two languages to program the meter from theselected remote interface. The programming language is

Connection to a Terminal or Printer (RS-232) The RS-232 connector on the meter’s rear panel is a 9-pin connector(DB-9, male connector). You can connec

CalibrationThis section gives a brief introduction to the calibration features of themeter. For a more detailed discussion of the calibration procedur

Chapter 4 Remote Interface Reference (continued)Null (Relative) Commands 145Input Filter Commands 146Math Operation Commands 148Statistics opera

To Unsecure for Calibration You can unsecure the meter forcalibration either from the front panel or remote interface. The meter issecured when ship

To Secure Against Calibration You can secure the meter againstcalibration either from the front panel or remote interface. The meter issecured when

To Change the Security Code To change the security code, you mustfirst unsecure the meter, and then enter a new code. Make sure you haveread the secu

Calibration Message You can use the calibration message feature to record calibrationinformation about your meter. For example, you can store suchinfo

Defaults, Power-On and Reset StatesThe meter stores settings in either volatile or non-volatile memory.Settings stored in volatile memory are returned

• Non-volatile memory settings can be returned to their factory defaults. Front Panel operation: return the settings to factory defaults underthe 11:

• Independent vs. common settings: Some settings are independent tothe channel or function being used and some are common to multiplechannels or funct

4Remote Interface Reference

Remote Interface ReferenceThis chapter is divided into the following sections:• Command Summary, page 117• Simplified Programming Sequence, page 126•

Command Summary This section summarizes the SCPI (Standard Commands forProgrammable Instruments) commands available to program the meter.Refer to the

Chapter 5 Error MessagesExecution Errors 201Self-Test Errors 208Calibration Errors 210Chapter 6 ApplicationProgramsHP BASIC Language Programs

Voltage Measurement Configuration Commands MEASure[:VOLTage][:DC]? [{<range> | AUTO | MIN | MAX | DEF}][,{<resolution> | MIN | MAX | DEF}]

Resistance Measurement Configuration Commands MEASure:FRESistance? [{<range> | AUTO | MIN | MAX | DEF}][,{<resolution> | MIN | MAX | DEF}]

Temperature Measurement Configuration Commands MEASure:TEMPerature? [{TC | THER | FRTD | DEF}][,{<type> | DEF}][, 1, {<resolution> | MAX |

General Measurement Configuration Commands CONFigure?[SENSe:]NULL [{OFF | ON | ONCE}]INPut:FILTer :STATe {OFF | ON} :STATe? :TYPE {ANALog | DIGital |

Triggering Commands INITiateREAD?TRIGger :SOURce {BUS | IMMediate | EXTernal} :SOURce?TRIGger :DELay {<seconds> | MIN | MAX} :DELay? [MIN | MA

System-Related Commands (continued)DISPlay[:STATe] {OFF | ON}DISPlay?DISPlay :TEXT <quoted string> :TEXT? :TEXT:CLEarSYSTem:ERRor?SYSTem:PRESetS

Calibration CommandsCALibration?CALibration:COUNt?CALibration :ICURrent?CALibration :OUTPut {ZERO | GAIN} :OUTPut?CALibration :SECure:CODE <new cod

IEEE-488.2 Common Commands*CLS*ESE <enable value> *ESE?*ESR?*IDN?*OPC*OPC?*PSC {0 | 1} *PSC?*RST*SRE <enable value> *SRE?*STB?*TRG*TST?*WA

Simplified Programming Sequence You can program the meter to take measurements from the remoteinterface using the following seven-step sequence.Throug

MEASure? and CONFigure DefaultsSetting SCPI Command System Defaults UsedCommon to all FunctionsInput Channel ROUTe:TERMinals Channel 1Digital Filter I

1Quick Start

Using the MEASure? Command The easiest way to program the meter for measurements is by using theMEASure? command. However, this command does not offer

Using the range and resolution Parameters With the MEASure? and CONFigure commands, you can select themeasurement function, range, and resolution all

Using the READ? Command The READ? command changes the state of the trigger system from the“idle” state to the “wait-for-trigger” state. Measurements w

Using the INITiate and FETCh? Commands The INITiate and FETCh? commands provide the lowest level of control(with the most flexibility) of measurement

MEASure? ExampleThe following program segment shows how to use the MEASure?command to make a measurement. This example configures the meter forvoltage

CONFigure Example 2The following program segment is similar to the example above but ituses INITiate to place the meter in the “wait-for-trigger” stat

The MEASure? and CONFigure CommandsSee also “General Measurement Configuration,” starting on page 55 inchapter 3. Both the MEASure? and CONFigure comm

MEASure[:VOLTage][:DC]:DIFFerence? [{<range> | AUTO | MIN | MAX | DEF}][,{<resolution> | MIN | MAX | DEF}]This command presets and makes a

CONFigure[:VOLTage][:DC]:DIFFerence [{<range> | AUTO | MIN | MAX | DEF}][,{<resolution> | MIN | MAX | DEF}]This command presets and confi

Setting the Function, Range, and Resolution See also “General Measurement Configuration,” starting on page 55 inchapter 3.[SENSe:]FUNCtion "<

Quick StartThis chapter helps you prepare the meter for use and contains exercisesdesigned to get you started with the meter, its menus, and the front

[{SENSe1: | SENSe2:}]VOLTage[:DC]:RANGe:AUTO {OFF | ON} [SENSe:]FRESistance | RESistance:RANGe:AUTO {OFF | ON}This command disables or enables autora

[SENSe1: | SENSe2:]VOLTage[:DC]:NPLCycles {0.02 | 0.2 | 1 | 2 | 10 | 20 | 100 | 200 | MIN | MAX}[SENSe:]FRESistance | RESistance:NPLCycles {0.02 | 0.2

Selecting the Input ChannelThe correct input channel is automatically selected for resistance andtemperature measurement functions. For voltage measur

Special Resistance Measurement CommandsThe following commands provide offset compensation and low power orvoltage limited resistance measurement capab

Temperature Measurement CommandsSee "Temperature Measurement Configuration" on page 71 in Chapter 3.• The meter stores the last settings use

[SENSe:]TEMPerature:TRANsducer:TYPE {TC | THER | FRTD | DEF}This command sets the type of temperature transducer to use fortemperature measurements. C

[SENSe:]TEMPerature:TRANsducer:FRTD:TYPE {85 | 91}This command sets the four-wire RTD type. The alpha is entered aseither 85 (for α = .000385) or 91 (

Null (Relative) CommandsThe meter uses independant null values for channel 1 and channel 2voltage measurements, resistance measurements, and temperatu

Input Filter CommandsSee also page 55 in Chapter 3.Using the input filters from the remote interface is not recommended. Touse the filters with the re

INPut:FILTer:STATe {OFF | ON}:STATe?These commands enable or disable the filter state and query the filterstate. INPut:FILTer:TYPE {ANALog | DIGital |

To Prepare the Meter For UseThe following steps help you verify that the meter is ready for use.1 Check the list of supplied items.Verify that you hav

Math Operation Commands See also “Math Operations,” starting on page 74 in chapter 3.There are two main math operations available; stats and scale, on

Statistics operation commands (AVERage) • You must have set CALC:FUNC AVER and CALC ON to use thesecommands.CALCulate:AVERage:MINimum? This command re

DATA:FEED RDG_STORE, {"CALCulate" | " "} This command selects whether readings taken using the INITiatecommand are stored in the

Triggering See also “Triggering,” starting on page 80 in chapter 3.The meter’s triggering system allows you to generate triggers eithermanually or au

IdleStateWait-for- Trigger State Delay Measurement SampleSampleCount >1Initiate TriggeringMEASure?READ?INITiateTrig

The Wait-for-Trigger StateAfter you have configured the meter and selected a trigger source, youmust place the meter in the wait-for-trigger state. A

Triggering Commands See also “Triggering,” starting on page 80 in chapter 3.INITiateThis command changes the state of the triggering system from the “

TRIGger:DELay {<seconds> | MIN | MAX}This command inserts a trigger delay between the trigger signal and eachsample that follows. If you do not

Chart Output (Analog Out) CommandsSee also "Chart Output", starting on page 98 in chapter 3.OUTPut[:STATe] {OFF | ON}[:STATe]?These commands

System-Related CommandsSee also “System-Related Operations,” starting on page 90 in chapter 3. FETCh?This command transfers readings stored in the met

If the Meter Does Not Turn OnUse the following steps to help solve problems you might experiencewhen turning on the meter. If you need more help, see

SYSTem:ERRor?This command queries the meter’s error queue. Up to 20 errors can bestored in the queue. Errors are retrieved in first-in-first out (FIFO

The SCPI Status Model All SCPI instruments implement status registers in the same way. Thestatus system records various instrument conditions in four

SCPI Status System + See page 169 for information on the use of this bit.Chapter 4 Remote Interface ReferenceThe SCPI Status Model 160

The Status ByteThe status byte summary register reports conditions from other statusregisters. Query data that is waiting in the meter’s output buffer

The status byte summary register is cleared when:• You execute a *CLS (clear status) command.• Querying the standard event and questionable data regis

Using *STB? to Read the Status Byte The *STB? (status byte query) command is similar to a serial poll exceptit is processed like any other instrument

How to Use the Message Available Bit (MAV)You can use the status byte “message available” bit (bit 4) to determinewhen data becomes available to read

The Standard Event Register The standard event register reports the following types of instrument events:power-on detected, command syntax errors, com

The standard event register is cleared when:• You send a *CLS (clear status) command.• You query the event register using the *ESR? (event status regi

The Questionable Data Register The questionable data register provides information about the quality of themeter’s measurement results. Overload cond

1 Remove the power cord. Removethe fuse holder assembly from the rear 2 Install the fuse. Remove theline-voltage selector from the assembly.250 m

The questionable data event register is cleared when:• You execute a *CLS (clear status) command.• You query the event register using STATus:QUEStiona

The Operational Status and Condition RegistersThe operation status register provides information about the operation ofthe meter. Bits in the operati

Bit Definitions — Operational Status RegisterBit Decimal Value Definition0 Not Used Always set to 01↓↓↓78 Filter Settled 256 Digital filter is settled

Status Reporting Commands SYSTem:ERRor?This command queries the meter’s error queue. Up to 20 errors can bestored in the queue. Errors are retrieved i

STATus:OPERation:EVENt? This command queries the Questionable Data event register. The meterreturns a decimal value which corresponds to the binary-we

*PSC {0 | 1} (Power-on status clear.) This command clears the Status Byte andStandard Event register enable masks when power is turned on (*PSC1). Whe

Calibration CommandsSee the Service Guide for a more detailed description of the meter’scalibration procedures.CALibration? This command performs a ca

CALibration:STRing <quoted string> This command records calibration information about your meter. Forexample, you can store such information as

RS-232 Interface Configuration See also “Remote Interface Configuration,” on page 101 in chapter 3.You connect the meter to the RS-232 interface using

RS-232 Data Frame Format A character frame consists of all the transmitted bits that make up asingle character. The frame is defined as the character

To Adjust the Carrying HandleTo adjust the position, grasp the handle by the sides and pull outward.Then, rotate the handle to the desired position. B

Refer to the cable and adapter diagrams below to connect the meter to mostcomputers or terminals. If you configuration is different than those describ

Connection to a PrinterTo connect to a printer you must use a DTE to DCE (Data CommunicationsEquipment) cable. Set the meter to the TALK ONLY mode by

The meter sets the DTR line FALSE in the following cases:1 When the meter’s input buffer is full (when approximately 100 charactershave been received)

RS-232 TroubleshootingHere are a few things to check if you are having problems using theRS-232 interface. If you need additional help, refer to the d

RS-232 Interface Commands SYSTem:LOCal This command places the meter in the local mode during RS-232operation. All keys on the front panel are fully f

An Introduction to the SCPI Language Standard Commands for Programmable Instruments (SCPI) defines howyou communicate with an instrument from a bus co

Using “ ? ” Commands The bus controller may send commands at anytime, but a SCPI instrument may only send responses when specificallyinstructed to do

SCPI Data Types The SCPI language defines different data formats for use in programmessages and response messages. Instruments are flexible listeners

Input Message TerminatorsProgram messages sent to a SCPI instrument must terminate with a<newline> character. The IEEE-488 EOI (end or identify)

Using Device Clear to Halt MeasurementsDevice clear is an IEEE-488 low-level bus message which can be used tohalt measurements in progress. Different

To Make Input ConnectionsUsing the Cable ProvidedAlign the front panel connector and cable conductors, press in. Tighten coupling nut.The connector an

To Set the HP-IB Address Each device on the HP-IB (IEEE-488) interface must have a uniqueaddress. You can set the meter’s address to any value between

To Select the Remote Interface The meter is shipped with both a HP-IB (IEEE-488) interface and anRS-232 interface. Only one interface can be enabled

To Set the Baud Rate You can select one of six baud rates for RS-232 operation. The rate is setto 9600 baud when the meter is shipped from the factor

To Set the Parity You can select the parity for RS-232 operation. The meter is configured foreven parity with 7 data bits when shipped from the facto

To Select the Programming Language You can select one of three language to program the meter from theselected remote interface. The language is SCPI

Alternate Programming Language Compatibility You can configure the 34420A to accept and execute the commands of the the Keithley 181 meter. Remote ope

SCPI Compliance Information The following commands are device-specific to the 34420A. They arenot included in the 1994.0 version of the SCPI standard.

INPut:FILTer[:LPASS]:DIGital:PREcharge {ON | OFF}:FILTer[:LPASS]:DIGital:PREcharge?:FILTer[:LPASs]:DIGital:RESPonse { SLOW | MEDium | FAST }:FILTer[:L

[SENSe:]TEMPerature:NULL[:STATe] { OFF | ON | 0 | 1 }:NULL[:STATe]? :NULL:VALue { <value> | MINimum | MAXimum }:NULL:VALue?:NPLCycles { &l

IEEE-488 Compliance Information Dedicated Hardware Lines Addressed CommandsATN Attention DCL Device ClearIFC Interface Clear EOI End or Identify REN R

Using a Custom CableRefer to page 272 for additional information about building custom inputcables. Channel 1HI LODCV + –4-WireΩSource + Source –2-Wir

5ErrorMessages

Error Messages When the front-panel ERROR annunciator turns on, one or morecommand syntax or hardware errors have been detected. A record of upto 20

Execution Errors -101 Invalid character An invalid character was found in the command string. You may haveinserted a character such as #, $, or % in

-112 Program mnemonic too long A command header was received which contained more than themaximum 11 characters allowed. Example: CONFIGURATION:VOLT:

-141 Invalid character data-144 Character data too long-148 Character data not allowedA discrete parameter was received but a character string or a nu

-221 Settings conflict This error can be generated in one of the following situations:You sent a CONFigure or MEASure command with autorange enabledan

-350 Queue overflow The error queue is full because more than 20 errors have occurred. No additional errors are stored until you remove errors from th

511 RS-232 framing error 512 RS-232 overrun error 513 RS-232 parity error 514 Command allowed only with RS-232 There are three commands which are only

750 Invalid channel nameThe meter received a MEAS or CONF command with an invalid channelspecifier.810 Invalid or unsupported transducer typeAn invali

Self-Test Errors The following errors indicate failures that may occur during a self-test.Refer to the Service Guide for more information.601 Front pa

To Measure VoltageChannel 1 Ranges: 1 mV, 10 mV, 100 mV, 1 V, 10 V, 100 VMaximum resolution: 0.1 nV (on 1 mV range)Channel 2 Ranges: 1 mV, 10 mV, 100

613 Ohms 5 uA source failed 614 Ohms 10 uA source failed 615 Ohms 100 uA source failed 616 Ohms 1 mA source failed 617 Ohms 10 mA source failed618 Ohm

Calibration Errors The following errors indicate failures that may occur during a calibration.Refer to the Service Guide for more information. 701 Ca

720 Cal DCV offset out of range 722 Cal RES offset out of range 723 Cal FRES offset out of range 730 Precharge DAC convergence failed 731 A/D turnover

6ApplicationPrograms

Application ProgramsThis chapter contains several remote interface application programs tohelp you develop programs for your measurement application.

HP BASIC Language ProgramsAll of the HP BASIC examples in this chapter were developed and testedon an HP 9000 Series 300 controller. Each device on th

HP BASIC / HP-IB Program Example 2This program example demonstrates how two input channels can beindependently configured and used. 10 !20 ! This

... continued260 PRINT ;Null_ch1 ! Print nulled reading270 !280 OUTPUT @Meter;"ROUT:TERM FRON2" ! Select cha

HP BASIC / HP-IB Program Example 3This program example demonstrates the use of an SRQ to indicate whenmeasurements are complete. The meter is set to u

... continued230 !240 ! Configure the GPIB interrupt system to generate an SRQ250 !260 Hpib=7 ! HP-IB select code

To Measure ResistanceRanges: 1 Ω , 10 Ω , 100 Ω , 1 kΩ , 10 kΩ , 100 kΩ , 1 MΩ Maximum resolution: 0.1 µ Ω (on 1 ohm range)See also Resistance Measure

... continued450 !460 ! Wait for "Operation Complete"470 !480 Task=1490 WHILE Task=1500 DISP "Reading..."510 WA

HP BASIC / HP-IB Program Example 4This program example demonstrates how data can be formatted and putin a file. The program also shows how to use math

... continued280 !************************************************************************290 Getdata: DEF FNGetdata(Address)300 REPEAT310 U

RS-232 Operations with QuickBASICThis program example uses QuickBASIC and the 82335B HP-IB Interface Card and command library for IBM® PC compatibles.

Microsoft Visual Basic Language ProgramThis example was created in Microsoft® Visual Basic for Windows. Theexample uses the 82335B and HP-IB control

... continuedRem Channel 1 measurement conf1$ = "CONF:VOLT:DC 1,0.01,(@FRON1)" errnum% = HpibOutputS(hHpib%, device&, conf1$, Len(

... continuedRem Nulled Channel 2 Measurement null_stmt$ = "SENS2:VOLT:DC:NULL ON" errnum% = HpibOutputS(hHpib%, device&, null_stm

... continuedRem Set up the meter errnum% = HpibOpen(isc&, hHpib%) Call check_srq errnum% = HpibReset(hHpib%, isc&) Call check_srq

... continued Rem Need to set timeout so that sampling and averaging can complete. Rem This assumes triggers occur at a rate high enough to be a

... continuedThe following subroutine may be included in the GLOBAL.BAS file.’ HPIB.DLL Access’ Put into your GLOBAL.BAS file•••Global isc As LongGlob

To Measure Temperature With ThermistorsThermistor type: 5 kΩTo Measure Temperature With RTDs4-wire, type: α = .00385 (DIN/IEC 751) or α = .00391R0 = 4

... continuedThe following function is used by the check_srq subroutine.Function HpibErrStr$ (errorcode As Integer)Select Case errorcode Case NOERR

C Language ProgramsAll of the C language example programs in this chapter are written forthe 82335 HP-IB Interface Card using the HP-IB Command Librar

• To compile Microsoft® QuickC® programs from the DOS commandline (using the "large" memory model), execute the following:qcl /AL <path..

C / HP-IB Example 1This example demonstrates the general sequence of programming andthe use of the MEASure? command to set and obtain a 4-wire Ohmsmea

... continued/**************************************************************************/void meter_meas(void){ /* Configure the meter for 4-wire ohm

C / HP-IB Example 2This program example demonstrates two input channels can beindependently configured and used. /************************************

... continued/**************************************************************************/void meter_meas(void){ /* Configure channel 1 for dc voltage

... continued /* Channel 2: Turn null on */ IOOUTPUTS(ADDR, "SENS2:VOLT:DC:NULL ON", 21); /* Place the null reading into the Null Registe

... continued/**************************************************************************/void command_exe(char *commands[], int length){ /* Execute o

C / HP-IB Program Example 3This program example demonstrates the use of an SRQ to indicate whenmeasurements are complete. The meter is set to use exte

To Measure Temperature With ThermocouplesThermocouple types: B, E, J, K, N, R, S, TReference: external thermistor, external fixed value, or internal

... continued/**************************************************************************/void rst_clear(void){ /* Reset the meter, clear the error qu

... continued/**************************************************************************/void meter_meas(void){ /* Configure the meter for dc voltage

... continued /* Use Serial Poll to read the Status Byte and clear all bits */ IOSPOLL(ADDR, &stat_cond); /* Call the function to check for err

Microsoft Excel Macro ExampleYou can use Windows Dynamic Data Exchange (DDE) to sendcommands to the meter and return measurement results directly int

Macro Comments• For simplicity, this macro is designed to output and enter data directlyonto the macro sheet. You may wish to output and enter data on

6Chapter 6 Application ProgramsMicrosoft Excel Macro Example 245

Chapter 6 Application ProgramsMicrosoft Excel Macro Example 246

7Measurement Tutorial

Measurement Tutorial The 34420A is capable of making highly accurate voltage, resistanceor temperature measurements. In order to achieve the greatest

Measurement Techniques and Sources of ErrorVoltage MeasurementsThe following table shows voltage measurement error sources. Each of thesesources of er

To Select a RangeYou can let the meter automatically select the range using autorangingor you can select a fixed range using manual ranging. • Autoran

Radio Frequency InterferenceMost voltage measuring instruments can generate false readings in thepresense of large high frequency fields. Possible sou

Thermal EMF ErrorsThermoelectric voltages are the most common source of error in low-leveldc voltage measurements. Thermoelectric voltages are generat

Rejecting Power-Line Noise VoltagesA desirable characteristic of integrating analog-to-digital (A/D)converters is their ability to reject spurious sig

Noise Caused by Ground LoopsWhen measuring voltages in circuits where the meter and thedevice-under-test are both referenced to a common earth ground,

Common Mode Rejection (CMR)Ideally, a meter is completely isolated from earth-referenced circuits.However, there is finite resistance and capacitance

Loading Errors Due to Input Resistance (dc volts)Measurement loading errors occur when the resistance of the device-under-test (DUT) is an appreciable

Loading Errors Due to Input Bias Current (Leakage Current)The semiconductor devices used in the input circuits of the meter haveslight leakage current

Noise Caused by Injected CurrentResidual capacitances in the power transformer cause small currents toflow from the LO of the meter to earth ground. T

Resistance MeasurementsSpecific resistance measurement techniques are discussed in thefollowing sections. You should also consider the techniques and

Offset CompensationA resistance measurement involves measuring a voltage (E) inducedacross the resistance by a known current source. Thermal EMF cause

To Set the Number of Digits You can set the display to show 41⁄2 , 51⁄2 , 61⁄2 , or 71⁄2 digits. In thisbook, the most significant digit (leftmost on

In the power-on state of the meter, offset compensation is enabled. Insome circumstances it may be desirable to turn offset compensation off.For examp

Output Clamping (Dry Circuit Testing)Resistance measurements on certain types of contacts may require alimitation on the voltage levels used to make t

Settling Time EffectsThe meter has the ability to insert automatic measurement settlingdelays. These delays are adequate for resistance measurements w

Temperature MeasurementsA temperature measurement is either a resistance measurement or avoltage measurement, converted to a temperature mathematicall

RTDsAn RTD uses a metal (typically platinum) that changes resistance with achange in temperature. Your meter can measure this resistance and byknowing

ThermocouplesA thermocouple converts temperature to voltage. When two wires,composed of dissimilar metals, are joined, an open circuit voltage isgener

An ice bath is used to create a known reference temperature (0° C). Once the reference temperature and thermocouple type are known, thetemperature of

To make a more accurate measurement, the copper test leads of themeter should be extended closer to the measurement and the connectionsto the thermoco

In some measurement situations, however, it would be nice to remove theneed for an ice bath (or other fixed external reference). To do this, anisother

Type + lead - leadTemperature RangeProbe AccuracyCommentsBU.S.BritishDINJapaneseFrenchPlatinum – 30%RhodiumGrayN/ARedRedN/APlatinum– 60%RhodiumRedN/AG

To Set the Integration Time Integration time is specified in Number of Power Line Cycles (NPLC).You can set the NPLC to 0.02, 0.2, 1, 2, 10, 20, 100,

Thermocouple Measurement ErrorsThe meter allows you to use one of three types of temperature referencefor thermocouple measurements: • Fixed Reference

Cleaning the Connector ContactsBecause the meter uses connector contacts that are almost pure copper,they are subject to oxidation. Oxidation can caus

Input ConnectorChannel 1HI LODCV+ –4-WireΩSource + Source –2-WireΩSource and Sense + Source and Sense –ThermistorSource and Sense + Source and Sense –

Obtaining Parts For the Input ConnectorPart NumberDescription34104ALow thermal input connector (blank)34103ALow thermal 4-wire shorting plug34102ALow

8Specifications

ACCURACY SPECIFICATIONS ± (% of reading + % of range) [1]Function Range [2]TestCurrent24 Hour23°C ± 1°C90 Day23°C ± 5°C1 Year23°C ± 5°CTemperatureCoe

DC Voltage Noise Specifications *Observation PeriodRange2-MinuteRMSNoise2-MinutePeak-PeakNoise24-HourPeak-PeakNoise1 mV 1.3 nVRMS 8 nVpp 12 nVpp10 mV

TemperatureThermocouple Type B, E, J, K, N, R, S, TRange: -210° C to 1820° CThermistor5 kΩRange: -80° C to 150° CRTD4-wire, 4.9 Ω to 2.1 kΩtypes:α =

Triggering and MemoryReading HOLD Sensitivity 10%, 1%, 0.1%, or 0.01% of rangeSamples/Trigger 1 to 50,000Trigger Delay0 to 3600s; 10µs step sizeExtern

DimensionsChapter 8 Specifications34420A Nano Volt/Micro Ohm Meter280

Front-Panel Display Formats -H.DDD,DDD,D EFFFront-panel display format.6 digits 1.021,651 V This is the 1 V range, 61⁄2 digits are displayed."

To Calculate Total Measurement ErrorEach specification includes correction factors which account for errorspresent due to operational limitations of t

Understanding the " % of range" Error. The range error compensatesfor inaccuracies that result from the function and range you select. Ther

Difference ErrorExampleThis example demonstrates how to compute the total measurement errorwhen using the Difference Function. Assume a difference mea

Ratio ErrorExampleThis example demonstrates how to compute the total measurement errorwhen using the Ratio Function. Assume a ratio measurement is mad

Interpreting Meter SpecificationsThis section is provided to give you a better understanding of theterminology used and will help you interpret the me

ResolutionResolution is the numeric ratio of the maximum displayed value divided bythe minimum displayed value on a selected range. Resolution is ofte

24-Hour AccuracyThe 24-hour accuracy specification indicates the meter’s relative accuracyover its full measurement range for short time intervals and

IndexIf you have questions related to the operation of this meter, call 1-800-452-4844 in the United States, or contact your nearest* commands, 184*S

C (continued)conformity, declaration, 295connections, 17 - 182-wire ohms, 204-wire ohms, 20cleaning, 271computer, 177dc volts, 19difference, 4

F (continued)front panelcomma separator, 95display format, 26enable/disable, 94front panel message, 94front-panel, 2at a glance, 2keys , 2menu,

To Rack Mount the MeterYou can mount the meter in a standard 19-inch rack cabinet using one ofthree optional kits available. Instructions and mounting

M (continued)MicrosoftExcel, 242 - 246QuickC, 230 - 241Visual Basic, 223 - 229Microsoft Excel, 242 - 246min-max measurementsfront-panel, 46NNMRSe

R (continued)resolution, 24, 431/2 digit, 24, 26, 43front-panel keys, 24, 43half digit, 24, 43parameters, 129specification described, 286revisio

T (continued)thermocouple, 73color code, 269connections, 22described, 265errors, 251, 270external reference, 270fixed reference, 270internal re

DECLARATION OF CONFORMITYAccording to ISO/IEC Guide 22 and CEN/CENELEC EN 45014Revision: B.01 Issue Date: 18 July 2001 Document 34401A.DOCManufacturer

The 34420A is a 71/2 digit, high performance nanovolt, micro-ohmmeter. Its combination of bench-top and system features makes thismeter a versatile so

To rack mount a single instrument, order adapter kit 5063-9240.To rack mount two instruments side-by-side, order lock-link kit 5061-9694 and flange ki

2Front-Panel Operation

Front-Panel OperationThis chapter assumes you are familiar with the meter and menuoperations. You should also understand how to make connections for t

Front-Panel Menu ReferenceA: MEASurement MENU1: DIG FILTER Ø 2: INTEGRATE Ø 3: OCOMP Ω Ø 4: LOW POWER Ω Ø 5: LOW VOLT Ω Ø 6: LoV LIMIT Ω1: DIG FILTER

E: SYStem MENU1: RDGS STOREØ2: SAVED RDGS Ø3: ERRORØ4: TESTØ5: CHART OUT Ø6: CHART SPANØ7: CHART NULLØ8: DISPLAYØ9: COMMAØ10: PRESETØ11: REVISION1: RD

A Front-Panel Menu TutorialThis section is a step-by-step tutorial which shows how to use thefront-panel menu. We recommend that you spend a few minut

Messages Displayed During Menu UseTOP OF MENU -You pressed ∧ while on the menus level; this is the top level of the menu and you cannot go any high

Menu Example 1 The following steps show you how to turn on the menu, move up or down between levels, move across the choices on each level, and turn o

> > > > 4 Move across to the COMMA command on the commands level. > > > > There are eleven comm

Menu Example 2 The following exercise demonstrates how to use the menu recall featureas a shortcut to set the COMMA command back to its original setti

The Front-Panel at a Glance 1 Input channel select 5 Menu operation keys2 Measurement function keys 6 Range/number of digits displayed keys3 Math oper

Menu Example 3 Some commands in the menu require that you enter a numericparameter value. The following steps show you how to enter a number inthe men

v 5 Move down to edit the NULL VALUE parameter. The null value should be 0.000000 V when you come to this point in themenu for the first time. For

> > > > 9 Move the flashing cursor over to the units location. > > > Notice that the units are flashin

To Select an Input ChannelFor voltage measurements, you have two independent input channels. • Pressing Channel toggles the display between Channel

To Select a Range You can let the meter automatically select the range using autorangingor you can select a fixed range using manual ranging. • Autor

To Set or Change the Number of Digits You can set the display to show 41⁄2 , 51⁄2 , 61⁄2 , or 71⁄2 digits. In thisbook, the most significant digit (le

To Set the Integration Time Integration time is specified in Number of Power Line Cycles (NPLC).You can set the NPLC to 0.02, 0.2, 1, 2, 10, 20, 100,

To Make Null (Relative) MeasurementsEach null measurement, also called relative, is the difference between astored null value and the input signal. Se

To Store Minimum and Maximum Readings (Stats)You can store the minimum and maximum readings during a series ofmeasurements. The following discussion s

To Trigger the Meter You can trigger the meter from the front panel using single trigger or autotrigger. • Autotriggering is enabled when you turn on

The Front-Panel Menu at a Glance The menu is organized in a top-down tree structure with three levels.A: MEASurement MENU1: DIG FILTER 2: INTEGRATE

To Use Reading Hold The reading hold feature allows you to capture and hold a stable readingon the display. When a stable reading is detected, the me

To Make Voltage Ratio and Difference Measurements To calculate a voltage ratio, the meter measures the voltages applied to the Channel 1 input termina

To Use Reading Memory The meter can store up to 1024 readings in internal memory. Thefollowing steps demonstrate how to store readings and retrieve t

v > 6 Move down a level and then across to the “ON” choice. ON Auto/Man ENTER 7 Save the change and exit the menu.Notice that the Mem (mem

v 10 Move down a level to view the first stored reading.Reading memory is automatically turned off when you go to the“parameter” level in the menu

3Features and Functions

Features and FunctionsYou will find that this chapter makes it easy to look up all the detailsabout a particular feature of the meter. Whether you are

General Measurement ConfigurationThis section contains information to help you configure the meter formaking measurements. You may never have to chang

• Front Panel operation: Press Shift Filter and scroll to one of DIGITAL, ANALOG, or ANA + DIG . Press Enter to enable the filter type. Pr

Digital Filter• The digital filter is a moving average (boxcar) filter. Equal weightingis applied to all readings to calculate the displayed reading.

Display Annunciators*Turns on during a measurement.Adrs Meter is addressed to listen or talk over the HP-IB interface.Rmt Meter is in remote mode (usi

Integration Time Integration time is the period during which the meter’s analog-to-digital(A/D) converter samples the input signal for a measurement.

• Front Panel operation: Integration time can be set indirectly whenyou select the number of digits (See page 43). You can also set the integration ti

Reducing Measurement NoiseAt high resolutions and low measurement levels, measurement noise canbecome an important factor in the accuracy of your meas

30 minute measurement, ±0.5° C, zero input, rms noise (typical)• Front Panel operation: Integration time can be set indirectly whenyou select the numb

Number of Digits DisplayedFront Panel operation only. See also “Integration Time,” on page 58.• You can set the number of digits shown in the display

7 digits 0.003,256,4 Ω This is the 1 ohm range,71⁄2 digits are displayed."1⁄2" digit6 digits 0.216,569 mV This is the 1 mV range, 61⁄2

RangingYou can let the meter automatically select the range using autorangingor you can select a fixed range using manual ranging. Autoranging isconve

Overload DetectionThe 34420A uses both an analog and digital method to generate anoverload condition and display the OVLD message. An understanding of

Voltage Measurement ConfigurationInput ChannelsThe meter has two independent input channels for measuring dc Volts.You can make measurements on either

• Remote operation: The CONFigure and MEASure subsystems usean optional parameter to specify the input channel as either 1 or 2:CONF:VOLT:DC DEF, DEF,

The Rear Panel at a Glance1 Chassis ground 5 Voltmeter complete output terminal 2 Power-line fuse-holder assembly 6 External trigger input terminal 3P

Resistance Measurement ConfigurationThe meter can make 2-wire or 4-wire ohms measurements. The metercan compensate for voltages in the resistive circu

Offset Compensated MeasurementsOffset compensation removes the effect of any voltages in the circuitbeing measured. The technique involves taking two

Voltage Limited MeasurementsVoltage limited resistance measurements clamp the open circuit voltageto predefined limits. • Voltage limits apply only to

Temperature Measurement ConfigurationThis section contains information to help you configure the meter formaking temperature measurements. To measure

RTD Measurements• The meter supports RTDs with α = 0.00385 (DIN/IEC 751) or α = 0.00391. The nominal value of the RTD (R0) must be in the rangeof 4.9

Thermocouple Measurements• The thermocouple must be connected to the Channel 2 inputs. Be sureto observe the correct polarity. Thermocouple connection

Math Operations There are two math operations available, only one of which can beenabled at a time. You can choose to either scale the readings as the

Statistics• After you enable statistics, the first reading that the meter takes isstored as both the minimum and maximum value. The minimum isreplaced

• Remote operation: the math operations and registers are controlledusing math operation commands. First, select the math operation youwant to useCALC

Null (Relative) OperationWhen making null measurements, also called relative, each reading is thedifference between the input signal and a stored null

In This Book Quick Start Chapter 1 prepares the meter for use and helps you getfamiliar with a few of its front-panel features.Front-Panel Operation

• Front-panel operation: After enabling null, you can edit the storednull value by pressing Shift > (Menu Recall). Any previously storedvalu

Reading Hold The reading hold feature allows you to capture and hold a stable readingon the front-panel display. This is especially useful in situati

TriggeringThe meter’s triggering system allows you to generate triggers eithermanually or automatically, take multiple readings per trigger, and inser

IdleStateWait-for- Trigger State Delay Measurement SampleSampleCount >1Initiate TriggeringMEASure?READ?INITiateTrig

Trigger Source ChoicesYou must specify the source from which the meter will accept a trigger. • The trigger source is stored in volatile memory; the s

External Triggering In the external trigger mode, the meter willaccept a hardware trigger applied to the Ext Trig terminal. The metertakes one readin

Internal Triggering In the internal trigger mode (remote interfaceonly), the trigger signal is always present. When you place the meter inthe wait-fo

The Wait-for-Trigger StateAfter you have configured the meter and selected a trigger source, you must place the meter in the wait-for-trigger state. A

Number of Samples Normally, the meter takes one reading (or sample) each time it receives a trigger from the selected trigger source (if the meter is

Trigger DelayYou can insert a delay between the trigger signal and each sample thatfollows. This may be useful in applications where you want to allow

ContentsChapter 1 Quick StartTo Prepare the Meter For Use 13If the Meter Does Not Turn On 14To Adjust the Carrying Handle 16To Make Input Connec

• Front Panel operation (continued)To set the delay to 0 seconds, select the “parameter” level of the TRIG DELAY command. Move the flashing cursor to

Automatic Trigger DelaysIf you do not specify a trigger delay, the meter selects an automatic delayfor you. The delay is determined by function, range

System-Related Operations This section gives information on topics such as reading memory, errors,self-test, and front-panel display control. This inf

• Front-panel operation: enable readings storage under the 1: RDGS STORE command in the SYStem menu. The ‘Mem’annunciator lights in the display. Rec

Error ConditionsWhen the front-panel ‘ERROR’ annunciator turns on, one or morecommand syntax or hardware errors have been detected. A record of upto 2

Self-Test A power-on self-test occurs automatically when you turn on themultimeter. This limited test assures you that the meter is operational.This

Display ControlTo speed up your measurement rate, or for security reasons, you maywant to turn off the front-panel display. From the remote interface,

Comma Separators The meter can display readings on the front panel with or without acomma separator. This feature is available only from the front

SCPI Language Version The meter complies with the rules and regulations of the present versionof SCPI (Standard Commands for Programmable Instruments

Voltmeter Complete TerminalThe rear-panel VM Comp (voltmeter complete) terminal provides a low-truepulse after the completion of each measurement. Vol