Rockwell Automation Publication 1769-UM021G-EN-P - October 2015
145
Use I/O Modules with CompactLogix 5370 L1 Controllers
Chapter 7
Consider these points before completing the steps in this section:
•
This section describes how to connect a 24V DC power source to power
input or output devices that are connected to the embedded I/O or local
expansion modules of the CompactLogix 5370 L1 controller via FP+ and
FP- terminals.
For information on how to connect 24V DC power to the
CompactLogix 5370 L1 controller and the POINTBus™ backplane via
VDC+ and VDC- terminals on the removable connector, see
.
•
The external 24V DC power source that is connected to the FP+ and FP-
terminals
must be separate
from the power source that is dedicated to
power the controller via the VDC+ and VDC- terminals for only series A
controllers (see
•
You can use the external 24V DC power source that provides power to the
FP+ and FP- terminals to power other components or devices in the
application.
•
The external 24V DC power source that provides power to the FP+ and
FP- terminals can be installed on the same DIN rail as the external
24V DC power source that provides power to the VDC+ and VDC-
terminals or you can install the external 24V DC power sources on
separate DIN rails.
•
Use a power source that most effectively meets your application needs.
That is, calculate the power requirements of your application before
choosing a power source to avoid using a power source that far exceeds
your application requirements:
–
Limit field power current to 3 A or use a 1734-FPD module to avoid
blowing the internal fuse.
–
Install a user-replaceable fuse with overcurrent protection of 4…6 A @
52.5…68.25 A2t in line between the incoming power and the FP+
terminal.