©
National Instruments Corporation
15
cFP-21xx Quick Start Guide
6. Wire Power to the Compact FieldPoint System
Each cFP-21
xx
on your network requires an 11–30 VDC power supply.
1. Connect the positive lead of the
primary power supply to one of the
V1 terminals and the negative lead to
one of the C terminals.
2. If you are using a backup power
supply, connect the positive lead to
V2 and the negative lead to one of the
C terminals. The cFP-21
xx
uses the
power supply with the higher voltage
level. V2 is isolated from the other
V terminals.
3. Refer to the operating instructions for the power requirements of each
I/O module.
4. Use a separate power supply for each module that needs external power.
Caution
Cascading power defeats isolation between the cascaded
modules.
C
V1
V2
+
–
+
–
11–30 VDC
Primary Power Supply
11–30 VDC Backup
Power Supply
(optional)
