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Common Questions
This appendix lists common questions related to the use of the
SCXI-1104/C.
What is the difference between the SCXI-1104 and SCXI-1104C?
The SCXI-1104 has a fixed cutoff frequency of 2 Hz. The SCXI-1104C has
a fixed cutoff frequency of 10 kHz. They are identical in all other respects.
The SCXI-1104 is commonly used to measure slowly-varying medium-
voltage signals in a high-noise environment. The SCXI-1104C is
commonly used to measure time-varying medium-voltage signals.
What are the similarities and differences between the SCXI-1102/B/C
and the SCXI-1104/C?
These modules have a similar internal architecture. Each channel has its
own amplifier and filter, which makes scanning trouble-free compared to a
shared-amplifier-and-filter architecture. All 32 differential input channels
are multiplexed to a single output channel and then routed to the DAQ
device, either directly or through the SCXIbus. Both modules have a fixed
cutoff frequency.
You can configure the SCXI-1102/B/C for a gain of either 1 or 100 while
the SCXI-1104/C has a fixed gain of 0.1 only.
Can you use the SCXI-1104/C for mV measurements, such as
temperature measurement using thermocouples?
No. The SCXI-1104/C is optimized for medium-voltage measurements, not
low-voltage measurements. If you need to make low-voltage measurements
select the SCXI-1102/B/C instead.
Can you read the voltage produced by the temperature sensor on the
SCXI-1300 terminal block when it is attached to an SCXI-1104/C?
No. You can use only channels 0 through 31 to take voltage measurements.
Figure 5-1,
SCXI-1104/C Module Block Diagram
, shows that the
temperature sensor signal is not routed from the front signal connector to
the SCXI-1104/C multiplexer.
