Rockwell Automation 1734-IA2, User Manual

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121 Publication 1734-UM001D-EN-P - April 2008
Chapter
5
Calibrate Your Analog Modules
About This Chapter
Read this chapter for information about how to calibrate analog modules. Your
analog I/O module is factory-calibrated. You may choose to recalibrate your
module in your system to increase its accuracy for your specific application.
This chapter covers the following:
•
Tools required to calibrate analog modules
•
Calibrate analog current input modules
•
Calibrate analog current output modules
•
Calibrate analog voltage input modules
•
Calibrate analog voltage output modules
You do not have to configure a module before you calibrate it. If you decide to
calibrate your analog I/O modules first, you can configure it at the same time.
When you calibrate input modules, use current or voltage calibrators to send a
signal to the module to calibrate it.
When you calibrate output modules, use a digital multimeter (DMM) to
measure the signal the module is sending out.
IMPORTANT
Analog I/O modules can be calibrated on a channel by channel
basis or with the channels grouped together. Regardless of
which option you choose, we recommend you calibrate all
channels on your module each time you calibrate. This helps
you maintain consistent calibration readings and improve
module accuracy.
Calibration is meant to correct any hardware inaccuracies that
may be present on a particular channel or in your system. The
calibration procedure compares a known standard, either input
signal or recorded output, with the channel’s performance and
then calculates a linear-correction factor between the
measured and the ideal.
The linear-calibration correction factor is applied on every input
or output in the same manner to obtain maximum accuracy.