AMETEK XG Family Programmable DC - Manual (Page 267)

Calibration and Troubleshooting
M370430-01 Rev E 7-3
7
Main Voltage and Current Calibration Principle
Understanding the Problem
Figure 7-1 illustrates two sources of analog programming error: gain
error and offset error. Gain error is the departure from the ideal slope of
the measured versus programmed line. Offset error is the magnitude of
the measured value when the programmed value is zero. Calibrating one
will affect the other so an iterative calibraton procedure is used.
For best results, iterative calibration of gain and offset will be required.
After first calibration of both, repeat gain calibration for 90% of
maximum value and offset calibration for 10% of maximum value.
Repeat as neccesay.
M
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Programmed Value
Figure 7-1 Offset (Intercept) Error and Gain (Slope) Error
Gain Error
Offset Error