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On fixed mounted Masterpact NT and NW breakers, is it ok if there is some movement on the bottom terminals on the back of the breaker?

Issue:
Movement on the bottom terminals at the back of the Masterpact NT/NW Breaker.

Product Line:
Air Circuit Breakers

Resolution:
For Masterpact NT and NW breakers, fixed mounted, it is normal to have some movement on the bottom terminals on the back the breaker. Inside of the breaker, heavy braided copper conductors are used to connect those terminals to the movable contact assembly within the breaker. The load current flows through the braided conductors (not a rigid connection). This movement allows the breaker contacts to open and close correctly. When force is applied to a particular terminal, the amount of movement is related to tolerance stack-ups in the housing and terminals. The actual amount of movement may vary from one terminal to the next, and from breaker to breaker. The breaker support housing restricts the movement of the terminals to acceptable parameters. Therefore the movement of the terminals does not affect the operation of the breaker.