RS-485 Wiring
The PMC-340 provides one standard RS-485 port and supports the Modbus RTU protocol. Up to 32 devices can be connected on a RS-485 bus.
The overall length of the RS-485 cable connecting all devices should not exceed 1200m.
If the master station does not have a RS-485 communications port, a RS-232/RS-485 or USB/RS-485 converter with optically isolated outputs and
surge protection should be used.
Each PMC-340 comes with a 120Ω Termination Resistor. It is recommended that a single termination resistor be used at the end of the RS-485
bus to prevent signal reflection.
Basic Setup Parameters