Gain And Offset Calibration - DAQ VXI-SC-1000 User Manual

Chapter 5 Calibration

Gain and Offset Calibration

VXI-SC-1102 User Manual
and reading the measured value. This value, the DMM offset, must be
subtracted from all subsequent measurements.
Measure the submodule's output at the analog bus receptacle (see
Figure 1-1 for the location of this receptacle). Refer to Figure 5-1 to
connect the positive DMM input to MUX+ and the negative DMM input to
MUX-.
MUX-
Figure 5-1. Analog Bus Receptacle Pin Assignment
To determine the offset and gain calibration factors of the
VXI-SC-1102 for a given gain, perform the following steps for a
two-point calibration. For two-point calibration, it is best to use input
voltages that correspond to the signal range of interest. For example, to
measure bipolar voltages over the submodule's full input range, choose
-9.9 V/G (negative full-scale) and +9.9 V/G (positive full-scale) as your
two input voltages.
1. Select the desired channel. Set the channel gain to the desired gain.
2. Apply the input for the first calibration point. To select negative
full scale as the calibration point, apply -9.9 V/G for an input
voltage.
a. Apply the input voltage to the channel selected in Step 1.
MUX+ MUX- CAL-
MUX+ CAL+
5-34
CAL+
CAL-
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