What this MCCB carries and where it fits
The Siemens 3VA1150-5EF32-0DC0 is a SENTRON molded case circuit breaker, 3-pole, rated 50 A continuous current (Iu) with a TM240 thermal-magnetic overcurrent release. The 187 kA breaking capacity at 240 V AC handles high fault currents without upstream fuses.
Current rating and thermal derating
The 50 A rating holds flat from 40 °C up to 50 °C ambient. Above that it derates: 48 A at 55 °C, 47 A at 60 °C, 46 A at 65 °C, 45 A at 70 °C. If your panel internal ambient runs above 50 °C, size the load at the derated figure — not the nameplate 50 A. The TM240 release is a fixed thermal-magnetic type; no interchangeable trip unit, so the breaker is factory-set and sealed.
Breaking capacity across voltages
Rated short-circuit breaking capacity (Icu) drops as system voltage rises: 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, 17 kA at 690 V. At 480 V (common in North American industrial), the 415 V figure is the closest published — expect the actual rating to fall between 121 kA and 75.6 kA. For 690 V systems, the 17 kA limit means this breaker is only suitable where the prospective fault current is well below that.
Physical fit and panel integration
Dimensions: 130 mm height, 76.2 mm width (3-pole), 70 mm depth. The width matches the standard 3-pole MCCB footprint — drops into a panel lugged for 50 A class breakers. IP40 on the front means it's protected against solid objects over 1 mm but not sealed against moisture; keep it inside a rated enclosure. The 2 auxiliary switches (HQ type) are built in, and an undervoltage release is fitted — verify coil voltage against your control circuit before wiring.