Chapter 3
Connecting the Signals
DAQCard-1200 User Manual
3-8
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You should use the DIFF input configuration when any of the following
conditions are present:
•
Input signals are low level (less than 1 V).
•
Leads connecting signals to the DAQCard-1200 are greater than 15 ft.
•
Any input signal requires a separate ground-reference point or return
signal.
•
The signal leads travel through noisy environments.
Differential signal connections reduce noise pickup noise and increase
common-mode noise rejection. With these connections, input signals can
float within the common-mode limits of the input instrumentation
amplifier.
Differential Connections for Floating Signal Sources
Figure 3-3 shows how to connect a floating signal source to a
DAQCard-1200 that is configured for DIFF input mode. Configuration
instructions are included in the
section of
Chapter 2,