National Instruments 5124, Calibration Procedure

NI 5122/5124 Calibration Procedure

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External Calibration Options

External calibration involves both adjustment and verification. Adjustment 
is the process of measuring and compensating for device performance to 
improve the measurement accuracy. Performing an adjustment updates the 
calibration date, effectively resetting the calibration interval. The device is 
guaranteed to meet or exceed its published specifications for the duration 
of the calibration interval. Verification is the process of testing the device 
to ensure that the measurement accuracy is within certain specifications. 
Verification can be used to ensure that the adjustment process was 
successful, or to determine if the adjustment process needs to be performed 
at all. During verification, you must compare the measurement error to 
limits given in Tables 3 through 12.

This document provides two sets of test limits for most verification 
stages—the 

calibration test limits 

and the 

published specifications

. The 

calibration test limits are more restrictive than the published specifications. 
If all of the measurement errors determined during verification fall within 
the calibration test limits, the device is guaranteed to meet or exceed its 
published specifications for a full calibration interval (two years). For this 
reason, you must verify against the calibration test limits when performing 
verification after adjustment. If all of the measurement errors determined 
during verification fall within the published specifications, but not within 
the calibration test limits, the device is meeting its published specifications. 
However, the device will not necessarily remain within these specifications 
for an additional two years. The device will meet published specifications 
for the remainder of the current calibration interval. In this case, you can 
perform an adjustment if you want to further improve the measurement 
accuracy or reset the calibration interval. If some measurement errors 
determined during verification do not fall within the published 
specifications, you must perform an adjustment to restore the device 
operation to its published specifications.

The 

Complete Calibration

 section describes the recommended calibration 

procedure. The 

Optional Calibration

 section describes alternative 

procedures that allow you to skip adjustment if the device already meets its 
calibration test limits or published specifications.