Rockwell Automation 1791-XXXX ANALOG BLOCK I/O - Manual (Page 62)

Module Calibration
Chapter 7
7-7
5. Set the EX bit (bit 07 of BTW word 0).
For PLC systems: Monitor the DN bit (BTR word 0, bit 07) until it
is set (1).
For SLC systems: Allow at least 5 seconds before continuing.
6. Reset (0) the EX bit (BTW word 0, bit 07) and set (1) the HL bit
(BTW word 0, bit 06).
7. Apply full scale current (+20.000 milliamps) to the inputs you are
calibrating.
8. Set (1) the EX bit.
For PLC systems: Monitor the DN bit (BTR word 0, bit 07) until it
is set (1).
For SLC systems: Allow at least 5 seconds before continuing.
9. Verify the input calibration by doing the following:
Make sure your terminal is in decimal radix mode
Important: Input values are scaled in microamps.
Vary the input reference over the 0 to 20 milliamps range.
Make sure the module input indications in the appropriate BTR
words are within acceptable limits.
Repeat steps 3–9 if necessary
Important: At this point, if you are not satisfied with your calibration, you
can cycle power to the block to restore the previous calibration constants.
If you move on to Step 10 of this procedure, the present calibration data
constants will overwrite the previous constants, making the previous
constants inaccessible.
10. Set (1) the WR bit 11 (13) of BTW word 0.
For PLC systems: Monitor the OK bit 11 (13) of BTR word 0 until
it is set (1).
For SLC systems: Allow at least 5 seconds before continuing.
11. Exit the calibration mode.