Chapter 4 Signal Connections

National Instruments Corporation 4-13 DAQCard E Series User Manual

Figure 4-3 summarizes the recommended input configuration for both types of signal sources.

Figure 4-3.

Summary of Analog Input Connections

Input
Differential
(DIFF)
Single-Ended —
Ground
Referenced
(RSE)
Single-Ended —
Nonreferenced
(NRSE)
Floating Signal Source
(Not Connected to Building Ground) Grounded Signal Source
Examples
• Ungrounded Thermocouples
• Signal conditioning with isolated outputs
• Battery devices
Examples
• Plug-in instruments with
nonisolated outputs
+
-
+
-
V
1
ACH(+)
+
-
+
-
V
1
ACH(+)
ACH (-)
See text for information on bias resistors.
See text for information on bias resistors.
R
Signal Source Type
ACH (-)
AIGND
+
-
+
-
V
1
ACH
AIGND
+
-
+
-
NOT RECOMMENDED
ACH
+ Vg -
V
1
Ground-loop losses, Vg, are added to
measured signal
+
-
+
-
V
1
ACH
AISENSE
R
AIGND
+
-
+
-
V
1
ACH
AISENSE
AIGND
AIGND