Siemens 5SN3 G40A Three Phase Circuit Breaker

Siemens 5SN3G40A is a three‑pole circuit breaker rated for 40 amperes, built for use in 240/415 V AC electrical systems. As part of Siemens' G40A family, this 3‑pole device provides overcurrent protection for distribution circuits in commercial and light‑industrial panels. The compact molded‑case design fits standard Siemens enclosures and bus bars, delivering reliable protection against overloads and short circuits on all three phases. With a 40 A continuous current rating, it is appropriate for protecting feeders that power motors, pumps, fans, and other 3‑phase equipment, offering quick isolation when faults occur to minimize damage and downtime. The 5SN3G40A model designation helps ensure correct replacement compatibility in legacy Siemens installations, so verify panel compatibility and trip‑curve requirements before replacement. The unit is designed for 240/415 V operation, aligning with typical European and international three‑phase power distribution schemes.