152 Rockwell Automation Publication 1769-UM021I-EN-P - May 2018
Chapter 7 Use I/O Modules with CompactLogix 5370 L1 Controllers
Embedded Input Points
The embedded input points on the CompactLogix 5370 L1 controllers
support 2-wire and 3-wire input devices. Yo u ca n wir e th e inp ut d e v ices t o b e
powered in one of the following methods:
•By using an external power supply, as shown in Figure 19
- In this case,
you can monitor the input devices even if field power is interrupted, for
example, by the Master Control Relay (MCR).
This method is required if you must continue reading data from the
input devices when the embedded output terminals are disabled, for
example, when the use of a MCR disrupts output power.
•By using the V terminal on the embedded I/O module, as shown in
Figure 21
- In this case, you cannot monitor the input devices even if
field power is interrupted, for example, by the MCR.
Figure 19
and Figure 20 show examples of how to power 2-wire and 3-wire
input devices in your application.
IMPORTANT When using Figure 19
and Figure 20, use the following guidelines:
• With this wiring configuration, you can monitor the input devices even if
field power is interrupted, for example, by the MCR. The FP- connection
must be maintained as a reference for inputs to function.
• With this wiring configuration, the controller does not help protect field-
side devices from overcurrent draw conditions.
• Design your application so that power consumption does not exceed the
power supply ratings.
• The following figure is a wiring example that complies with the National
Electrical Code (NEC) standard for isolation between system and field
power.
• The FP+ terminal on the removable connector is the voltage connection.
• The FP- terminal on the removable connector is the common
connection.
• The MCR must be closed for the removable connector to provide power
to the embedded I/O module.
• Install a user-replaceable fuse with overcurrent protection of
4…6 A @ 52.5…68.25 It in line between the incoming power and the
FP+ terminal.
For series A L1 controllers only, you must use a separate, dedicated Class 2
power supply for the CompactLogix 5370 L1 controller and a separate power
supply for the embedded I/O module (see Appendix C
).
To Next Page
Loading...
Need help?
General
