The Allen-Bradley 140U-J2D3-D15 Circuit Breaker is an Inverse Time Molded Case Circuit Breaker (MCCB) with 3-poles and it is manufactured in a J-Frame as part of the 140U family of circuit breakers. It has a continuous current rating of 150 Amps, and an Interrupting Rating or Breaking Capacity that ranges between 20 and 29 kA. The Allen-Bradley 140U-J2D3-D15 Circuit Breaker is used for providing the overcurrent protection that is needed in motion control applications. It can be used as a part of a motor starter system with additional disconnect switches and contactors, or it can be used by itself for protecting the feeding lines supplying power to motor control installations. The end-users can manually configure only the magnetic tripping point because the thermal protection trip point is not user-adjustable and it comes preset by default from the factory.

As an Inverse Time Molded Case Circuit Breaker, the Allen-Bradley 140U-J2D3-D15 Circuit Breaker has a varying response speed that depends on the magnitude of the incoming overcurrent the device is sensing. This circuit breaker will open faster if the incoming overcurrent is of a very high magnitude. When the incoming overcurrent is of a lower magnitude, the circuit breaker will react slowly, tripping only after some time has passed to allow the process to stabilize itself before interrupting the circuit. Allen-Bradley designed this type of system to provide high-speed protection against over-currents and to prioritize process stability for lower overcurrent. As with any breaker, the manufacturer recommends mounting the 140U-J2D3-D15 Circuit Breaker in a suitable enclosure or inside a properly designed space to guarantee a longer lifespan and avoid unnecessary failures.