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RM-4339 Calibration Procedure

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© National Instruments

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9

d.

Compare the values obtained in step c with those in Table 5.

e.

Clear the task by calling DAQmx Clear Task.

Quarter-Bridge Shunt Calibration Accuracy Verification

Complete the following procedure to verify the quarter-bridge shunt calibration accuracy of the 
RM-4339:
1.

Set the calibrator to standby mode (STBY).

2.

Using an RJ50 cable connect the calibrator to the channel of the RM-4339 you want to 
verify.

Note

Only one channel can be connected to the calibrator at a time.

a.

Connect EX+ (pin 6) to 

 HI, connect QTR (pin 5) to 

 LO and connect AI+ (pin 2) 

to 

 LO as shown in Figure 2.

Figure 2.  

RJ50 to Calibrator Connections

b.

QTR and AI+ must be connected together at the calibrator. The EX+ lead wire and the 
QTR lead wire must be the same length.

3.

Set the calibrator output to 120 

, 350 

, or 1000 

 depending on the quarter-bridge 

configuration you want to verify. This must match the configuration setting made in step 6 a.

4.

Set the calibrator output for compensation off (COMP off).

5.

Set the calibrator to operate mode (OPR) to enable the output.

Table 5.  

Offset Voltage Accuracy Limits

Range (V)

Test Point (V)

Lower Limit (V)

Upper Limit (V)

Minimum

Maximum

-0.1

0.1

0

-0.000010

0.000010

C

a

li

b

r

a

tor

RJ50 Connector
on the RM-4

33

9

HI

LO

EX+ (pin 6)

AI+ (pin 2)

QTR/R

S

-

(pin 5)

Norm

a

l

Ω

 O

u

tp

u

t

Содержание RM-4339

Страница 1: ...curacy Verification 9 Specifications 12 World Wide Support and Services 13 Software Calibrating the NI RM 4339 requires the installation of NI DAQmx on the calibration system Driver support for the RM...

Страница 2: ...dware setup NIPXIe 4339 User Manual NI PXIe 4339 specific information NI PXIe 4339 Specifications NI PXIe 4339 specifications and calibration interval NI DAQmx Readme Operating system and application...

Страница 3: ...r and can sink 15 mA on the 120 setting 8 mA on the 350 setting and 3 mA on the 1 k setting Ohm Meter NI PXI 4070 If this instrument is unavailable use a 6 digit DMM with 2 wire resistance measurement...

Страница 4: ...how to install and use the RM 4339 Test Conditions The following setup and environmental conditions are required to ensure the RM 4339 meets published specifications Keep connections to the RM 4339 a...

Страница 5: ...erification procedures assume that adequate traceable uncertainties are available for the calibration references SCA Shunt Calibration Resistance Accuracy Verification This section provides instructio...

Страница 6: ...hunt Cal c Commit the task by calling DAQmx Control Task with the following parameter Action Commit 4 Take a resistance measurement from the DMM and record the result 5 Compare the result from step 4...

Страница 7: ...n of the environment should be kept within 1 C between measurement of the offset error of the NI PXIe 4339 and the offset measurement of the RM 4339 Complete the following steps to verify the offset v...

Страница 8: ...nector on the back of the RM 4339 4 Connect an RJ50 cable to each channel with AI pin 2 and AI pin 3 connected to T pin 9 5 Acquire voltage measurements from all channels with the NI PXIe 4339 a Creat...

Страница 9: ...connect QTR pin 5 to LO and connect AI pin 2 to LO as shown in Figure 2 Figure 2 RJ50 to Calibrator Connections b QTR and AI must be connected together at the calibrator The EX lead wire and the QTR l...

Страница 10: ...erage the readings that you acquired and record the values as ResultSCD g Clear the task by calling DAQmx Clear Task 7 Acquire an AI Bridge V V measurement with shunt calibration enabled a Create a ta...

Страница 11: ...47 for 350 SCalExp 0 00248756 for 1 k For reference the calculation for the expected shunt calibration deflection is given by the following equation where Req is the equivalent parallel resistance of...

Страница 12: ...e Test limits in this document are based upon the March 2015 edition of the NI PXIe 4339 and RM 4339 User Guide and Terminal Block Specifications Refer to the most recent NI PXIe 4339 and RM 4339 User...

Страница 13: ...ivate expense and is subject to the applicable limited rights and restricted data rights as set forth in FAR 52 227 14 DFAR 252 227 7014 and DFAR 252 227 7015 World Wide Support and Services The Natio...

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