Rockwell Automation 1771-IR , D17716.5.76 RTD INPUT MODULE - Manual (Page 34)

Chapter
7Ć1
Module Calibration
In this chapter we tell you how to calibrate your modules.
In order to calibrate your input module you will need the following tools and
equipment:
Tool or Equipment Description Model/Type Available from:
Industrial Terminal and
Interconnect Cable
Programming terminal for A-B
family processors
Cat. No. 1770-T3 or Cat. No.
1784-T45, -T50, etc.
Allen-Bradley Company
Highland Heights, OH
Precision Resistors 1.00 ohm, 1% (quantity of 6) CMF-65-0010-F-T-0 Dale
402.0 ohm, 0.01% (quantity of 6) MAR6-T16-402-.01% TRW
You must calibrate the module in an I/O chassis. The module must
communicate with the processor and industrial terminal.
Before calibrating your module, you must enter ladder logic into the processor
memory, so that you can initiate BTWs to the module, and the processor can
read inputs from the module.
Calibration can be accomplished using either of two methods:
auto–calibration
manual
calibration
Auto–calibration calibrates the input by generating offset and gain correction
values and storing them in EEPROM. These values are read out of EEPROM
and placed in RAM memory at initialization of the module.
The auto–calibration routine operates as follows:
- Whenever a block transfer write (BTW) is performed to the module (any
time after the module has been powered up), it interrogates word 15 for a
request for auto–calibration.
- The request can be for the following: offset calibration, gain calibration,
save operation (save to EEPROM).
When using auto–calibration, write transfer calibration words 9 through
14 must contain zeroes.
Chapter Objective
Tools and Equipment
Calibrating your Input
Module
About Auto-calibration