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Motor Logic Plus II - Communication Connection

Issue:
Is the communication connection port on the Motor Logic Plus II a RS-232 connection?

Product Line:
Overload Relays

Environment:
US Product

Cause:
Product Specifications

Resolution:
NOTE: Each 9065SPxxx requires a communication module to connect to the RS-485 network.

It is important to recognize that the nine-pin connector on the 9065 SPxxx is NOT an RS-232 connector! A converter is required to change the RS-485 signal to RS-232.

The 9065 SPxxx is connected to high AC voltages with a floating ground circuit. As long as there are three balanced line voltages present, the resulting ground level will often be near case ground. However, if one phase is lost or if the line voltages become unbalanced, the floating ground may be as much as 480 volts above the case ground. The communication module has two high speed optical isolation chips on the Receive and Transmit pins and a low speed opto-isolator on the Transmit/Receive pin to isolate the communication network from the AC line voltages.

In addition, a separate isolated power supply system provides power for the transceiver used for RS-485 level conversion.

Master Device I/O Port
Your MODBUS master device should have an RS-485 port. If your master device only has RS-232 ports, an RS-232 to RS-485 converter will be required. Before ordering a converter, you may need to know if you can program your master device to independently control the RTS (Request-To-Send) line. Some RS-232 to RS-485 converters use the RS-232 signal called RTS to turn on the RS-485 lines before transmitting a command. If your master device cannot control the RTS line, you will need to order an RS-232 to RS-485 converter that automatically turns on the RS-485 line whenever a command is being written.

IMPORTANT
DO NOT PLUG A MODEM OR ANY OTHER PC-COMPATIBLE SERIAL DEVICE INTO THE 9-PIN CONNECTOR OF THE PRODUCT!
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