Chapter 4
Connecting the Signals
©
National Instruments Corporation
4-19
Figure 4-9.
Single-Ended Input Connections for Ground-Referenced Signals
Common-Mode Signal Rejection Considerations
Figures 4-7 and 4-9 show connections for signal sources that are already
referenced to some ground point with respect to the NI 6052E. In these
cases, the PGIA can reject any voltage caused by ground potential
differences between the signal source and the device. In addition, with
DIFF input connections, the PGIA can reject common-mode noise pickup
in the leads connecting the signal sources to the device. The PGIA can
reject common-mode signals as long as V
in
+ and V
in
– (input signals) are
both within ±11 V of AIGND.
Measuring More than Eight Channels
with the DAQPad-6052E for BNC
The DAQPad-6052E for BNC is designed to measure up to eight
differential channels using BNC connectors and cabling. To measure more
than eight channels, use one of the single-ended modes. Up to
16 single-ended channels are available in the single-ended modes.
To use a single-ended mode, change the source type (FS/GS) switch
settings on the device front panel. Figure 4-10 shows the switch locations.
Selected Channel in NRSE Configuration
Common-
Mode
Noise
and Ground
Potential
Ground-
Referenced
Signal
Source
PGIA
Input Multiplexers
–
+
–
+
V
s
V
cm
I/O Connector
AIGND
AISENSE
ACH
–
+
Instrumentation
Amplifier
Measured
Voltage
V
m
–
+
