MPM-UN Modbus connection polarity

Issue

The modbus RS485 connectors on the MPM-UN are marked MOD A & B, the documentation does not state the polarity.

Product Line

SmartStruxure Lite

Environment

MPM-UN

Modbus

Cause

Documentation does not state the polarity of the Modbus connectors.

Resolution

Connect the Modbus device to the A-B connectors on the MPM. Connect the positive lead to connector A and the negative lead to connector B.