National Instruments 6110, Calibration Procedure

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© National Instruments Corporation 13 NI 6110/6111/6115/6120 Calibration Procedure
Adjusting the Device
Use the NI 6110/6111/6115/6120 calibration procedure to adjust the
analog input and output calibration constants. At the end of each calibration
procedure, these new constants are stored in the factory area of the device
EEPROM. The user cannot modify these values. This limitation provides a
level of security that ensures users cannot accidentally modify any
calibration constants adjusted by the metrology laboratory.
This portion of the calibration process calls functions from NI-DAQ as well
as functions from the
niECal.dll
. For further information on the
functions in the
niECal.dll
, refer to the comments in the
niECal.h
file.
To adjust the analog inputs with a calibrator, complete the following steps:
1. Read the Equipment and Other Test Requirements section.
2. Connect the positive output of the calibrator to analog input
channel 0+ (pin 68).
3. Connect the negative output of the calibrator to analog input
channel 0– (pin 34) and to ACH0GND (pin 67).
4. Call
Get_Cal_Date
to obtain the date of the last calibration. The
function is included in the
niECal.dll
. After running, CalDate
contains the date that the device was last calibrated.
5. Call
Calibrate_E_Series
to internally calibrate the device. Set the
following parameters:
• deviceNumber —The value obtained from MAX
• calOP —
ND_SELF_CALIBRATE
• setOfCalConst —
ND_USER_EEPROM_AREA
• calRefVolts —
0
Note It may take as long as 60 seconds to complete this function call for the
NI 6110/6111/6115 and as long as five minutes for the NI 6120.
6. Set the calibrator to output a voltage of 7.50 V for the
NI 6110/6111/6115 and 5.0 V for the NI 6120.
7. Call
Calibrate_E_Series
. Set the following parameters:
• deviceNumber —The value obtained from MAX
• calOP —
ND_EXTERNAL_CALIBRATE
• setOfCalConst —
ND_USER_EEPROM_AREA
• calRefVolts —7.50 V for the NI 6110/6111/6115 and 5.0 V for
the NI 6120
If the voltage supplied by the source does not maintain a steady 7.50 V
for the NI 6110/6111/6115 or 5.0 V for the NI 6120, you receive an