Chapter 3
Configuring Your SCXI Hardware and Software
3-30
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However, you must adjust the configuration if any of the following
conditions is true:
•
Your input signals are floating or nonreferenced.
•
You are cabling this SCXI-1140 directly to a DAQ device and you
are using a Lab/1200 device, or you are using an MIO or AI device in
SE mode.
•
You require a gain other than 1 on any channel.
•
You are using digital modules and are cabling the SCXI-1140 to a
DAQ device.
Read the rest of this section on the SCXI-1140 module if any of these
conditions applies to you.
Use the following procedure to configure your SCXI-1140 module:
1.
Configure the signal referencing modes. Table 3-21 lists the
SCXI-1140 signal referencing configurations.
2.
Configure the instrumentation amplifier output referencing mode.
The output referencing mode is relevant only if this SCXI-1140 is
connected directly to a plug-in DAQ device. Table 3-22 lists the
SCXI-1140 instrumentation amplifier signal referencing
configurations.
Table 3-21.
SCXI-1140 Signal Referencing Jumper Configuration
Jumpers
Description
Configuration
AB—Connects the instrumentation amplifier
negative input to the front panel connector only
(factory-default position). Use this setting to
measure ground-referenced source signals.
BC—Connects instrumentation amplifier negative
input to the front panel connector and to module
analog ground through a 100 k
Ω
resistor (for
floating sources). Use this setting to measure
floating signals with this channel.
W1-W2 W3-W6 W7-W8
A
B
C
A
B
C
