Ceiec Electric Technology
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2.5 Communications Wiring
The following figure illustrates the RS485 communications connections on the PMC-53:
Figure 2-9 Communications Connections
The PMC-53 provides one RS485 port and supports the Modbus RTU protocol. Up to 32 devices can
be connected on a RS485 bus. The overall length of the RS485 cable connecting all devices should
not exceed 1200m.
If the master station does not have a RS485 communications port, a RS232/RS485 or USB/RS485
converter with optically isolated output and surge protection should be used.
2.6 Digital Input Wiring
The following figure illustrates the Digital Input connections on the PMC-53:
Figure 2-10 DI Connections
2.7 Digital Output Wiring
The following figure illustrates the Digital Output connections on the PMC-53:
Figure 2-11 DO Connections