About 1756 analog I/O module calibration
The 1756 I/O analog modules are calibrated at the factory. Calibrate the module to increase its accuracy for your specific application.
The calibration procedure compares a known standard, either input signal or recorded output, with the channel's performance and then calculating a linear correction factor between the measured and ideal values. The same linear correction factor is applied every input or output to obtain maximum accuracy.
To obtain the best possible accuracy in measurement, recalibrate the module every six months.
IMPORTANT:
- Calibration should not be performed on a module currently being used for control. The channels will freeze at their current values, and control may be interrupted.
- Calibration disrupts control involving the module.
- Calibration disconnects the module from the control signals to which it is normally connected and connects it to reference signals.
- During calibration, output modules do not update their outputs with the data values requested by the controller. Outputs may transition based on the calibration process itself if that channel is being calibrated.
- During calibration, the controller is not receiving measurements of signals, originating in the system under control, from the input module.
There are two general functions in the calibration process:
- Attaching a Low Reference Signal
- Attaching a High Reference Signal
Calibrate input channels first and output channels second. The
Logix Designer
application calibration screens guide you through the entire process. Provide Feedback