National Instruments DAQ Series User Manual

Chapter 3 Connecting Signals
DAQCard-700 User Manual 3-10 ni.com
Differential Connections for Grounded Signal Sources
Figure 3-4 shows how to connect a ground-referenced signal source to a
DAQCard-700 card configured for DIFF input.
Figure 3-4. Differential Input Connections for Grounded Signal Sources
With this type of connection, the instrumentation amplifier rejects both the
common-mode noise in the signal and the ground potential difference
between the signal source and the DAQCard-700 ground (shown as V
cm
in
Figure 3-4).
DAQCard-700 Device in DIFF Configuration
Grounded-
Referenced
Signal
Source
Common-Mode
Noise,
Ground
Potential,
and so on
V
s
V
cm
I/O Connector
17
18
1,2
Measured
Voltage
V
Instrumentation
Amplifier
ACH<0..7>
ACH<8..15>
Input Multiplexers
AIGND

National Instruments DAQ Series Specifications

General

Brand	National Instruments
Model	DAQ Series
Category	Recording Equipment
Language	English