National Instruments VXI-SC-1102 - Manual (Page 33)

Chapter 5 Calibration
VXI-SC-1102/B/C User Manual 5-2 © National Instruments Corporation
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-.
Figure 5-1. Analog Bus Receptacle Pin Assignment
Gain and Offset Calibration
To determine the offset and gain calibration factors of the
VXI-SC-1102/B/C submodules 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+ CAL-
MUX+ MUX- CAL- CAL+