The 140U-J3D3-C90 Molded Case Circuit Breaker (MCCB) is a high-performance compact breaker from Allen-Bradley/Rockwell Automation. It has a size J frame, 3 poles, and 250 Amps of current rating. The rated operational voltage of the breaker is 400/480 Volts AC and the current rating is 90 Amps. The 140U-J3D3-C90 Molded Case Circuit Breaker (MCCB) comes with 35 Kiloamps of interrupting rating and it weighs about 11.4 pounds. The protection type of the breaker is the fixed thermal/adjustable magnetic type. The breaker can be used to provide overcurrent protection such as short circuit protection and thermal over-current protection to industrial control panel applications. The 140U-J3D3-C90 Molded Case Circuit Breaker has an arc chamber that draws the arc generated by contact away from the contact to let it cool down.

The 140U-J3D3-C90 Molded Case Circuit Breaker offers adjustable thermal protection and fixed magnetic protection while maintaining the overall circuit breaker volume. One of the most important factors to be considered when selecting the breaker is the interrupting rating. To determine the interrupting rating, calculate the amount of fault current that can be delivered at a point of a system where the breaker is applied and the interrupting rating of the breaker must be greater than or equal to the amount of fault current at that particular point of the circuit. This MCCB can be used as a current limiting circuit breaker that allows less energy to dissipate during short circuit conditions than traditional UL 489 circuit breakers do. This MCCB has the ability to be mounted in a separate enclosure that is rated to withstand different environmental conditions such as dust, water, and oil. It can be applied for electrical systems in commercial buildings, institutional buildings, industrial plants, and high rise residential buildings.