National Instruments NI 6738, Calibration Procedure

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NI 6738/6739 Calibration Procedure | © National Instruments | 25
5. Use the DMM to read the value of AO 0.
6. Call DAQmxClearTask with the following parameter:
•
taskHandle
: taskHandle
7. Call DAQmxInitExtCal with the following parameters:
• deviceName : Dev_name
• password : NI
• calHandle : &calHandle
8. Call DAQmx
AO
SeriesCalAdjust with the following parameters:
• calHandle : calHandle
• referenceVoltage : Value read from DMM
9. Call DAQmxCloseExtCal with the following parameters:
• calHandle : calHandle
• action : DAQmx_Val_Action_Commit
This function also saves the date, time, and temperature of the adjustment to the onboard
memory.
Note If an error occurs during adjustment, no constants are written to the
EEPROM.
10. Disconnect the DMM from the device.
EEPROM Update
When an adjustment procedure is completed, the NI 6738/6739 internal calibration memory
(EEPROM) is immediately updated.
If you do not want to perform an adjustment, you can update the calibration date without making
any adjustments by initializing an external calibration (using the
DAQmxInitExtCal
function
call) and closing the external calibration (using the
DAQmxCloseExtCal
function call).
Reverification
Repeat the Verification section to determine the as-left status of the device.
Note If any test fails reverification after performing an adjustment, verify that you
successfully self-calibrated the device, as described in the Self-Calibration section,
before returning your device to NI. Refer to Worldwide Support and Services for
assistance in returning the device to NI.