Model3490A

SectionIII

 

S E C T I OINII

O P E R A T I NI NGS T R U C T I O N S

3 - 1 .I N T R 0 D U C T I 0 N .

3-2.This section contains instructions for using the Model 34904 Multimeter to make dc voltage,ac voltage and resistance measurements.It also includes instructions for sample/hold and ratio measurements,remote control and data output. Basic operating instructions may be found on a pull-out card at the bottom edgeof the 3490A front Panel.

3.3.INSTBUMENTCAPABILITIES.3-4.StandardInstrument.

3-5. The standardModel 3490A Multimeter makes dc voltage, ac voltage and resistancemeasurementswith S-digitresolution and up to I 20 % of rangeon all ranges except l000Vac to dc. The 3490A has five dc voltage ranges, .l V to 1000V; 4 ac voltage ranges, I V to 1000V; and six resistanceranges,I kO to 10,000kQ. Rangingmay be manualor automatic.Polarity selection and display are automatic.A self-testfeatureis included which checkscertain operationswithin the instrument.

3-6. Outputand RemoteGontrol0ptions.

3-7. Data Output Option 021 and Remote Control Option 022. Option 021 providesten columnsof binary coded decimal (BCD) output data. This data may be either HIGH true or LOW true, as selectedby a slide switch on the outguard data output printed circuit assembly. With Option O22, the 349OA range and function may be programmed by LOW true input information. External triggering is possible with either option.

3-8. General Purpose Interface Bus ll0 Option

030.The General Purpose Interface Bus I/O (GPIB) option permits remote programmhg and dataoutput on the samebus lines. The 3490A may be connectedto a bus in parallel with several other instruments and controlled by a singlecontrolling instrument. Remote control of range,function, triggermode and sample/hold mode is possible with Option 030. The output data includesmeasurementstatus,function, polarity, magni- tude and range,in the format given in Paragraph3-126. Controlling instruments that may be used with the 3490A GPIB option include the -hp-9800A series calculators and the -hp-Model 3260A Marked Card Programmer.

3-9.Sample/Hold0ption040or045.

3-10. The Sample/HoldOption(040 or 045) enablesthe \todel 3-190.{ Multimeter to sample a changinginput

voltageand hold that samplelong enoughto measureits amplitude. This permits pulse height measurementsand digitization of changingwaveformssuchasrampsor sine waves.The extemal trigger circuits areisolatedfrom the signal input Low terminal and from chassisground, which allows the voltmeter to make guarded floating measurementsThe. designationsused for the 34904 Sample/Holdoptions areasfollows:

WhenSample/Holdis installed The Sample/Holdoption

in a 3490A with:

is designatedas:

BCDiRemoteExpand Option 020 Option 040

GPIB Option 030

Option 040

Neither020 or 030

Option 045

3-11Batio.0ption080.

3-12. The 3490A equipped with Ratio Option 080 is capable of making three-wire dc-to-dc or ac-to-dc ratio measurement.Two External Referencerangesare pro- vided, the I V range accepting referencevoltages of 10.1 V to t 1.2V, and the 10V rangeaccepting voltagesfrom t I V to t 12V.

3 . 13FRONT.ANDREARPANELOESCRIPTION .

3-14. Figure3-l showsthe front and rearpanelcontrols and connectorsand gives a brief descriptionof each. Some of the features shown are available onlv with certainoptions.

, . 3 - 15MAXIMUM.INPUTVOLTAGES .

3-l 6. Table 3-l lists the maximum allowablevoltages betweeninput terminals,and betweenthe terminalsand chassis.Thesemaximum voltagesare also shown on the front panel and must not be exceededor damageto the instrumentmay resull.

wAR]ililG

If the 34904 has a rear input connector,

the front and rear terminals are internally connected in puallel. If high voltagesmay

be applied, always protect the open termi- nals. Be ilre the rear input terminals are open before connecting an input to the front terminals and vice versa.

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