Communication Wiring on a Masterpact Fix Mount Breaker

Product Line
Powerpact P, Masterpact NT, Masterpact NW, Compact NS

Environment
Installing or troubleshooting breaker communications

Resolution


The figure above displays the communication components of a fix mount insulated case breaker. Schneider Electric circuit breakers that come in this configuration are the Powerpact P frame, Masterpact NT and NW, and Compact NS.  Below are descriptions of the components labeled C and D.

Fixed Terminal Block (C)

The terminal block is design to be inserted into particular slot at the top of the breaker. The slot is marked with terminal E1-E6. The terminal assignments are as follows:

• E1(+), E2(-) : The terminal supplies 24 VDC to the BCM. (It does not supply the trip unit or its display)
• E3(-), E4(+):  These are the transmit (Tx) terminals for 4 wire RS-485 communication.
• E5(-), E6(+):  These are the receive (Rx) terminals for 4 wire  RS-485 communication.

The incoming wires to these terminals can come from any RS-485 communications chain or Schneider Electric devices designed for breaker communications like the IFE and IFM modules. See knowledge article FA261785 for more information on circuit breaker communications. The output of the terminal goes to the Trip Unit Breaker Communications Module (BCM). Depending on the type of breaker there may be a plug that connects to the BCM (Masterpact).


Breaker Communication Module or BCM (D)

The BCM is installed a behind the trip unit and communicates with trip unit through an infrared port. There is a connector at the top of the unit to bring in the power and communication from the terminal block.

Released for: Schneider Electric Canada