Line protection MCCB with serious interrupting capacity
The Siemens SENTRON 3VA1150-5EF36-0JA0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection, carrying a continuous current Iu of 50 A across the ambient range from 40 °C to 50 °C before it begins to derate — at 70 °C it still holds 45 A, which is useful for a warm panel. The interrupting ratings are the headline here: 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at 690 V. That 187 kA figure at 240 V means this breaker can safely clear a fault at the full available short-circuit current of a large industrial service entrance or a high-capacity transformer secondary — it's not a branch-circuit MCCB; it's sized for a main or a high-fault subfeed. It uses a TM240 thermal-magnetic overcurrent release and includes a shunt trip (STL) as the auxiliary release. No undervoltage release, no auxiliary contacts, no communication module, no ground-fault monitoring — this is a straightforward, no-frills power breaker for a main feeder where you need high interrupting capacity and a simple trip curve.
Panel fit and mounting
The 3VA1150-5EF36-0JA0 measures 70 mm deep, 76.2 mm wide, and 130 mm high. The 76.2 mm width is a standard 3-pole MCCB footprint — it occupies three 25.4 mm module positions on a DIN rail or a panel-mount base plate. The 70 mm depth means it clears most standard enclosure back-panels without a deep-can extension. Front protection is IP40, which is typical for a panel-mounted breaker — it keeps out tools and fingers but is not sealed against washdown. Mount it inside a cabinet, not on an open wall in a wet area.