The Allen-Bradley 140U-J0D3-D22 Circuit Breaker is a 3-pole, J-Frame, Inverse Time, Molded Case Circuit Breaker (MCCB) that is part of the Allen-Bradley 140U series. Its continuous current rating is 220 Amps. The Interrupting Rating or Breaking Capacity of the Allen-Bradley 140U-J0D3-D22 Circuit Breaker is higher than 100 kA. Typical applications for this device are as protection against overcurrent in the feeding lines that supply the power to motor control installations. The Allen Bradley 140U-J0D3-D22 Circuit Breaker is often part of a tandem system of other elements such as disconnect switches and contactors that act as motor starters in motion control applications. Only the magnetic tripping point can be manually configured by the end-users because the thermal protection setting is not user-configurable.

An interesting feature of the Inverse Time Molded Case Circuit Breakers such as the Allen-Bradley 140U-J0D3-D22 Circuit Breaker is that they will quickly open the circuits if the incoming overcurrent is of a very high magnitude. If the incoming overcurrent is of a lower magnitude, the circuit breaker's reaction will be slower, and the breaker will trip 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 overcurrents and prioritize process stability on low-intensity events. The Allen-Bradley 140U-J0D3-D22 Molded Case Circuit Breaker has several optional accessories available, including but not limited to Auxiliary Contacts, Rotary Operators, Internal Control Modules, and Flex Cable Operators. Like with any breaker, the manufacturer recommends mounting the 140U-J0D3-D22 Circuit Breaker in a suitable enclosure or inside a properly designed space to guarantee a longer lifespan and to avoid unnecessary failures.