Rockwell Automation 1771-IXHR , D17716.5.80 HIGH RESOL.THERMOCOUPLE - Manual (Page 39)

Module Calibration
Chapter 7
7Ć5
Save Calibration Values
If any ”uncalibrated channel” bits (bits 08–15 of BTR word 13) are set, a save
cannot occur. Auto–calibration should be performed again, starting with offset
calibration. If the module has a faulty channel, the remaining functioning
channels can be calibrated by inhibiting calibration on the faulty channel.
The module can be run with the new calibration values, but will lose them on
power down. To save these values, proceed as follows:
1. Request a ”save to EEPROM” by setting bit 02 in BTW word 28 and
sending the BTW to the module. Refer to Table 7.A.
2. Queue BTRs to monitor for ”save complete”, ”EEPROM fault” and
”calibration fault.” An EEPROM fault indicates a nonoperative EEPROM;
a calibration fault indicates at least one channel was not properly offset or
gain calibrated and a save did not occur.
You calibrate each channel by applying a precision voltage to the input
terminals, comparing correct with actual results, and entering correction into the
corresponding calibration word for that channel. The correction takes affect
after it is transferred to the module by the corresponding BTW instruction in
your ladder diagram program. Always start with offset adjustment followed by
gain adjustment.
Before calibrating the module, you must enter ladder logic into processor
memory, so that you can initiate write block transfers to the module, and the
processor can read inputs from the module. Write transfers will contain
calibration values in words 20 through 27 for the channel you are calibrating.
Use a precision voltage source, such as Data Precision 8200 or equivalent, for
your calibration input voltage.
Setting Channel Offset Calibration
1. Select the millivolt range and zoom = 0.
2. Apply 0.000 millivolts to the channel input as shown in Figure 7.3.
Performing Manual Calibration