National Instruments NI PCI-5922, Manual

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NI 5922 Calibration Procedure

9.

Calculate the error in timing as parts per million (ppm) using the following formula:

where

a

 = the measured frequency

Compare the result to the 

Calibration Test Limits

 or the 

Published Specifications

 listed in 

Table 7. If the result is within the selected test limit, the device has passed this portion of 
the verification.

Adjusting the NI 5922

If the NI 5922 successfully passed each of the verification procedures within the calibration test 
limits, then an adjustment is recommended but not required to guarantee its published 
specifications for the next two years. If the oscilloscope was not within the calibration test limits 
for each of the verification procedures, you can perform the adjustment procedure to improve 
the accuracy of the oscilloscope. Refer to the 

External Calibration Options

 section to determine 

which procedures to perform.

An adjustment is required only once every two years. Following the adjustment procedure 
automatically updates the calibration date and temperature in the EEPROM of the oscilloscope.

Note

If the oscilloscope passed the entire verification procedure within the 

calibration test limits and you do not want to perform an adjustment, you can update 
the calibration date and onboard calibration temperature without making any 
adjustments by completing 

only

 steps 4 and 13 in this section.

Complete all of the following steps to externally adjust the NI 5922.
1.

Connect the scope calibrator to the channel 0 input of the oscilloscope. Configure the 
calibrator to output an exact 1 MHz sine wave with 1 V peak-to-peak amplitude and 1 M

Ω

load impedance.

2.

Connect the DC source calibrator to the channel 1 input of the oscilloscope. Configure the 
DC source calibrator to output an exact 4 V DC signal into a 1 M

Ω

 load impedance 

(channel 1).

3.

Wait 3,000 ms for the calibrator to settle.

4.

Call 

niScope_CalStart

 (niScope Cal Start VI) using the user password. The factory 

default password for the NI 5922 is 

NI

.

5.

Call 

niScope_CalSelfCalibrate

 (niScope Cal Self Calibrate VI) with the following 

parameters:
•

channelList

: 

VI_NULL

•

option

: 

VI_NULL

Table 7.  

NI 5922 Timing Accuracy

Calibration Test Limit

Published Specification

±5.3 ppm

 ±50 ppm

error

a

2,000,000

–





2

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