Chapter 7, 7 - calibrating the module, About the procedure – Rockwell Automation 1746-BTM Barrel Temperature Control Module User Manual User Manual

Page 61: Calibration codes and status, About the procedure -1, Calibration codes and status -1, Calibrating the module, Chapter

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Publication 1746-UM010B-EN-P - April 2001

Chapter

7

Calibrating the Module

About the Procedure

Calibrate the module after the first 6 months of operation. Then check
the calibration and re-calibrate only if necessary once a year.

Use this procedure to store calibration values for each channel in
EEPROM. Calibration sets channel accuracy at 0.05% of full range
regardless of channel circuit tolerances. You can calibrate the input
channels individually or in groups. The thermocouple/mV operation
of all channels is suspended during calibration.

Calibration Codes and Status

Use the following format for entering calibration code words and
reading calibration status bits. Enter calibration values in hexadecimal.
You read channel status bits at different steps in the calibration
procedure, one bit for each channel you are calibrating.

Use Word 14 (Output Image) for entering calibration codes

Use Words 4 and 5 (Input Image) for reading calibration status

Code Word 5

Status Word 4

Status Word 5

Calibration codes in Hex

Channel status during
calibration

Channel status at
completion
of calibration

15

12

11

08

07

04

03

00

15

12

11

08

07

04

03

00

15

12

11

08

07

04

03

00

1

0

0

1

OK status bits (1=OK) for channels 3,2,1,0
(high-end calibration) @

OK status bits (1=OK) for channels 3,2,1,0
(low-end calibration) @

OK status bits (1=OK) for channels 3,2,1,0
(low-end calibration) @

Channel status words 6 and 7 display “CAL4” during calibration

@ Reads F Hex if all four channels are OK

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