Rockwell Automation Allen-Bradley 1794-IRT8K, User Manual

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39 Publication 1794-6.5.12 - September 2011
Chapter
5
Calibrate Your Module
Overview
This chapter provides the tools and equipment, and procedure for calibrating
your FLEX I/OThermocouple, RTD, and mV input module.
When and How to
Calibrate Your FLEX I/O
Module
This module is shipped to you already calibrated. If a calibration check is
required, the module must be in a FLEX system. We recommend recalibrating
your module, if the module is going to be used in an environment with
temperature other than 25 °C (77 °F) and 30% humidity.
Calibration can be accomplished using the manual calibration procedure
described in the following sections.
Topic Page
When and How to Calibrate Your FLEX I/O Module 39
Tools and Equipment 40
Calibrate Your Input Module 40
Calibration Setup 41
Wiring Connections for Calibrating the Thermocouple and RTD
Input Module
41
Read and Write Words for Calibration 42
EDT Calibration Command and Command Data Summary 44
Offset Calibration 45
Gain Calibration 46
Current Source Calibration 47
Cold Junction Calibration 49
Channel Loop Compensation Calibration 49
Chapter Summary 49
ATTENTION
Perform module calibration periodically, based on your application, or
at least once a year. Module calibration may also be required to
remove module error caused by aging components in your system.
Offset calibration must be done first, followed by gain calibration.
IMPORTANT
You must use a 1794-TB3G or 1794-TB3GS terminal base when
calibrating this module.