What it is and what it does
The Siemens SENTRON 3VA1150-4EF36-0JC0 is a 3-pole molded case circuit breaker (MCCB) designed for line protection in industrial power distribution. It carries 50 A continuously at 40 °C and can interrupt fault currents up to 75.6 kA at 415 V — that's the kind of headroom that keeps a fault from cascading upstream and taking out a whole switchboard. Rated insulation voltage is 800 V, so it's comfortable in 400/415 V systems with margin. Maximum power loss is 14.6 W, which matters when you're packing several breakers into a panel and need to manage heat rise.
Breaking capacity — the real numbers
This breaker's interrupting rating varies with system voltage: 121 kA at 240 V, 75.6 kA at 415 V, 52.5 kA at 440 V, and 11.9 kA at both 500 V and 690 V. The 415 V figure is the one most panel builders will care about for a 400 V three-phase distribution board — 75.6 kA covers most industrial service entrances without needing a current-limiting upstream device.
Thermal performance and derating
Rated 50 A from 40 °C up to 50 °C ambient. Above that it derates: 49 A at 55 °C, 48 A at 60 °C, 46 A at 65 °C, and 45 A at 70 °C. Operating range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. If your panel sits in a hot machine room or near a furnace, factor the derating into your load schedule.
Built-in accessories and options
This variant comes with two HQ auxiliary switches and a shunt trip (STL) release for remote tripping. No undervoltage release, no ground-fault monitoring, no communication module — it's a straightforward line-protection breaker with basic signaling and remote trip capability. The auxiliary switches can feed a PLC input for breaker status, and the shunt trip lets a safety relay or emergency-stop circuit kill power remotely. No trip indicator on the front, so you'll rely on the auxiliary switch feedback or a visual check of the handle position. Voltage trigger is present, meaning it can respond to an undervoltage condition if wired accordingly — but the undervoltage release itself is not installed on this unit.