Welding System User Manual

Chapter 2 Function Reference — AI_Configure
© National Instruments Corporation 2-9 NI-DAQ FRM for PC Compatibles
Using This Function
When you attach an SC-2040 or SC-2042-RTD to your DAQ device, you must configure
channels 0 through 7 for differential mode. When you attach an SC-2043-SG or any SCC
accessories to your DAQ device, you must configure these channels for nonreferenced
single-ended mode. On the AT-MIO-16X, 16-bit E Series, AT-MIO-16F-5, and
AT-MIO-64F-5 devices, the calibration constants used for analog input change depending
on the polarity of the analog input channels. NI-DAQ always ensures that the calibration
constants in use match the current polarity of the channels.
See the
Calibrate_E_Series function description for information about calibration
constant loading on the E Series devices.
If you change the polarity on AT-MIO-16X, AT-MIO-64F, and AT-MIO-16F-5 by calling
AI_Configure, NI-DAQ uses the following guidelines to ensure that appropriate constants
are loaded automatically:
• AT-MIO-16X—NI-DAQ checks if the load area contains the appropriate constants. If so,
NI-DAQ will load the constants from the load area. Otherwise, NI-DAQ will load the
constants from the factory area for the current polarity and return status code
calConstPolarityConflictError.
• AT-MIO-64F-5—This device has separate caldacs for unipolar and bipolar input.
Therefore, NI-DAQ does not need to reload calibration constants.
• AT-MIO-16F-5—The load area on this device contains constants for both unipolar and
bipolar input. Therefore, NI-DAQ will load the appropriate constants from the load area
for the current polarity.
Note
The actual loading of calibration constants will take place when you call an AI,
DAQ, or SCAN function. On the AT-MIO-16X, the need for reloading the constants
will depend on the polarity of the channel on which you are doing analog input.
Note
The PCI-6110E and PCI-6111E support differential bipolar operation only.