What this MCCB is and what it does
The Siemens 3VA1150-5EF36-0AH0 is a SENTRON molded case circuit breaker (MCCB) designed for line protection in distribution panels. It carries a continuous current rating of 50 A at 40 °C through 50 °C, derating to 45 A at 70 °C, so the thermal curve governs real-world panel loading — not just the nameplate number. The TM240 overcurrent release combines a thermal bimetal for overload protection and a magnetic coil for short-circuit response, set for a 240 A magnetic trip threshold.
Breaking capacity — what the voltage columns mean
This 3-pole MCCB delivers 187 kA interrupting capacity at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at both 500 V and 690 V. The steep drop above 440 V is typical for a frame this size — at 690 V the available fault current must stay under 17 kA or you step up to a larger frame. Rated insulation voltage is 800 V, which covers 690 V systems with margin.
Panel fit and auxiliaries
Footprint is 76.2 mm wide, 130 mm tall, 70 mm deep — standard SENTRON 3VA1 frame dimensions. The breaker ships with a basic switch 3VA11505EF360AA0 and accepts up to 2 auxiliary switches plus 1 trip alarm switch (HQ configuration), which covers remote status indication without an external interface module. Power loss at rated current is 14.6 W, worth factoring into enclosure thermal calculations if the panel is densely populated.