Chapter 3 Connecting Signals
SCB-68 Shielded Connector Block User Manual 3-2 ni.com
Figure 3-1. Summary of AI Connections
+
–
+
–
+
–
V1
ACH
AISENSE
AIGND
+
–
+
–
V1
ACH
AIGND
+
–
+
–
V1
ACH(+)
ACH(–)
AIGND
+
–
+
–
V1
ACH(+)
ACH(–)
AIGND
R
Refer to the

Using Bias Resistors

section for information on bias resistors.
Signal Source Type
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
Input
Differential
(DIFF)
Single-Ended —
Ground
Referenced
(RSE)
Single-Ended —
Nonreferenced
(NRSE)
+
–
+
–
+
–
Common-
Mode
Voltage
Common-
Mode
Voltage
Common-
Mode
Voltage
+
–
Common-
Mode
Voltage
+
–
Common-
Mode
Voltage
Common-
Mode
Voltage
Refer to the

Using Bias Resistors

section for information on bias resistors.
+
–
+
–
V1
ACH
+ Vg –
AIGND
Ground-loop losses, Vg, are added to
measured signal.
NOT RECOMMENDED
+
–
+
–
V1
ACH
AISENSE
AIGND
R