The 140G-J2F3-D20 is a J-frame molded case circuit breaker that has been designed and produced by Allen-Bradley/Rockwell Automation to provide protection to control systems against short circuit currents and abnormal currents that could cause anomalies in the operating process. It comes with fixed thermal and fixed magnetic mechanisms that work as a complement to each other in order to perform precise circuit-breaking functions. The Allen-Bradley 140G-J2F3-D20 J-frame molded case circuit breaker has an interrupting capacity of 25 kiloamps. Fixed thermal circuit breakers are temperature-sensitive. This means that at a temperature below 40 degrees Celsius, it is possible that the breaker will carry more current than its current rating allows. For temperatures above 40 degrees Celsius, the breaker might carry less current than it is rated for.

The Allen-Bradley/Rockwell Automation 140G-J2F3-D20 J-frame molded case circuit breaker can be placed inside an enclosure that also provides an installation mechanism. Circuit breakers are similar to fuses, but the advantage of circuit breakers is that once these have performed a tripping action, they can recover and start operating again almost immediately. The disadvantage of fuses is that they are a 1-time protection means and once they have tripped, they need to be replaced by new fuses. Circuit breakers like the 140G-J2F3-D20 circuit breaker are a more economical choice than fuses in many applications. The Allen-Bradley 140G-J2F3-D20 J-frame molded case circuit breaker comes with a current rating of 200 Amps and it is a fixed magnetic and fixed thermal circuit breaker with 3 poles and a frame current rating of 250 Amps.