Cannot establish CANbus communication between MPM controllers.

Issue

Cannot establish CANbus communication between MPM controllers.  

Product Line

SmartStruxure Lite

Environment

MPM controllers, any version

Cause

The CANbus trunk is missing the end of line resistors on the two end MPM controllers.  Each of the MPM controllers which are at the end of the CANbus trunk must have an 120 ohm resistor installed.

Resolution

Install a 120 ohm resistor at both ends of the CANbus trunk.