National Instruments SCC-CI20 User Manual page 5

Using the SC-C120 when Scaling Voltage Measurements
© National Instruments Corporation
The input resistors are socketed so that you can replace them when
necessary. Figure 2 shows the locations of the input and spare resistors.
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5
1 Input Resistor for AI (X )
2 Product Name
3 Assembly Number
Figure 2. SCC-CI20 Parts Locator Diagram
For information about how to configure the SCC-CI20 module using
NI-DAQmx, refer to the SCC Quick Start Guide.
If you configured the SCC-CI20 using Measurement & Automation
Explorer (MAX) and you are using NI-DAQ, the reading you get from the
E Series DAQ device accounts for the voltage-to-current conversion and
returns milliamps, not volts. Otherwise you must convert the raw voltage
measurement to a current measurement. To make this conversion, use the
following formula:
where I is in milliamps and V is in volts.
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2
4 Spare Resistors
5 Input Resistor for AI (X+8)
V
I
= ------------ -
0.249
5 SCC-CI20 Current Input Module User Guide
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