The Allen-Bradley 140G-K6F3-D40-MU Circuit Breaker is a 3-pole Molded Case Circuit Breaker (MCCB) that is supplied from the factory with a universal busbar adapter option that can be mounted on the top or bottom of the MCCB. The terminal lugs for the connection of the breaker to the busbar can also be ordered separately.  Like all the MCCBs that use the K Frame, the Allen-Bradley 140G-K6F3-D40-MU Circuit Breaker has a current rating of 400 Amps. It also comes with an interrupting rating or breaking capacity of 65 kA and 2 screw-type adjustment knobs located on the front side of the breaker for setting the thermal and magnetic tripping points in a range from 280 to 400 Amps for the thermal trip (Ir) and from 2000 to 4000 Amps for the magnetic trip (Im). Some of the additional accessories that can be installed in the Allen-Bradley 140G-K6F3-D40-MU Molded Case Circuit Breaker are the auxiliary contacts, undervoltage trip, trip contact blocks, and the shunt trip.

Working on busbar mounted components like the Allen-Bradley 140G-K6F3-D40-MU Molded Case Circuit Breaker requires a special type of training the work should only be done by highly skilled and qualified electrical technicians. High currents passing through the busbars can generate electrical arcs that could potentially injure or kill a person in less than a second, so all the required precautions should be taken to ensure the safety of the technicians when servicing or maintaining the MCCB. It is also important to remember that the busbars can remain very hot even after they are de-energized. The Allen-Bradley 140G-K6F3-D40-MU Molded Case Circuit Breakers can be used for locking and tagging procedures.