Rockwell Automation 1771-IXHR , D17716.5.80 HIGH RESOL.THERMOCOUPLE - Manual (Page 42)

Module Calibration
Chapter 7
7Ć8
2. Record the input value read by the processor in the BTR file (word 4 for
channel 1). Determine the percentage difference from 10000 and the sign
of the correction.
You can adjust the correction up to +0.19379%.
A negative correction means that the reading was too high and you want
to subtract a corrective amount from that reading.
A positive correction means that the reading was too low and you want to
add a corrective amount to that reading.
For example, if the observed value was 10014, then 10000–10014 = –14,
and –14 divided by 10000 = –0.14%.
3. Using the following table, select gain correction values that most nearly
add up to the percentage that you determined in step 1. Select a value only
once.
Bit Value
Bit 07 Sign bit
Bit 06 = 0.0976562%
Bit 05 = 0.0488281%
Bit 04 = 0.024414%
Bit 03 = 0.012207%
Bit 02 = 0.00610351%
Bit 01 = 0.00305175%
Bit 00 = 0.00152587%
Enter the bit code representing the sum of the corrections into the lower
byte (gain correction) of the calibration word for that channel.
For example, to attain the value of 0.140%, you would add:
Percentage Bit Number
0.0976562 Bit 06
0.024414 Bit 04
0.012207 Bit 03
0.00610351 Bit 02
Total = 0.1403807%
Enter 11011100 in the lower byte of the calibration word for that channel.
This entry would set bits 07 (sign) and 06, 04, 03 and 02 which is
–0.1403807, very close to the required –0.14. Remember to keep the
upper byte the same as it was from step 5.