Chapter 3
Configuring Your SCXI Hardware and Software
©
National Instruments Corporation
3-23
6.
Configure the amplifier output referencing.
The signal output referencing is relevant only if you connect the
SCXI-1121 module directly to a DAQ device.
Use jumper W33 to configure the various output referencing modes
of the SCXI-1121 amplifier. The correct output referencing mode
depends on the input mode of the DAQ device you use.
Table 3-16 shows the three possible signal referencing configurations.
7.
If you are using any digital SCXI modules in serial mode and will
connect the SCXI-1121 module to the plug-in DAQ device, configure
the SCXI-1121 module to connect the MISO signal to the
SERDATOUT pin (jumper W38).
SCXI-1122 Module
This module has 16 isolated input channels and two isolated excitation
channels. The SCXI-1122 is a module for signal conditioning of strain
gauges, RTDs, thermistors, thermocouples, volt and millivolt sources,
4 to 20 mA current sources, and 0 to 20 mA process-current sources. The
SCXI-1122 can operate in two modes. Use the two-wire scan mode with all
16 input channels used for input or the four-wire scan mode with the eight
upper channels configured as sense leads for connecting input channels and
Table 3-16.
SCXI-1121 Amplifier Output Referencing Jumper Configuration
Jumper
Description
Configuration
A-R0R1—Parking position. Use this setting
for MIO or AI devices in DIFF input mode
(factory-default position).
AB-R2—Select this position for AI and MIO
devices in NRSE mode.
AB-R0—Connects the amplifier reference to
data acquisition analog ground, pins 1 and 2 of
the rear signal connector. Use this position for
DAQ devices with SE inputs, such as the Lab
and 1200 devices, or MIO and AI devices in
RSE mode.
W33
R2 R1 R0
A
B
R2 R1 R0
A
B
R2 R1 R0
A
B
