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NI 5922 Calibration Procedure
3.
Call
niScope_CalSelfCalibrate
(niScope Cal Self Calibrate VI) with the following
parameters:
•
sessionHandle
: The instrument handle that you obtain from
niScope_init
(niScope Initialize VI)
•
channelList
:
VI_NULL
•
option
:
VI_NULL
Because the session is a standard session rather than an external calibration session, the new
calibration constants are immediately stored in the EEPROM. Therefore, you can include
this procedure in any application that uses the oscilloscope.
4.
Call
niScope_close
(niScope Close VI) to close the session handle. Set the following
parameter:
•
vi
: The instrument handle you obtained from
niScope_init
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 must be
performed. During verification, you must compare the measurement error to limits given in
Tables 3 through 7.
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
section describes the recommended calibration procedure. The
section describes alternative procedures that allow you to skip adjustment
if the device already meets its calibration test limits or published specifications.
