What this MCCB carries and where it fits
The Siemens 3VA1150-3EF36-0DH0 is a SENTRON molded case circuit breaker (MCCB) rated 50 A continuous at 40 °C through 50 °C, with a 3-pole construction and line-protection trip curve. It carries a full-load interrupting capacity of 75.6 kA at 240 V AC, 52.5 kA at 415 V, and still holds 11.9 kA at 690 V — enough to handle most industrial fault currents without cascading upstream breakers. An integrated undervoltage release (UVR) and two auxiliary switches plus a trip alarm switch (HQ) come built in, so you don't need to add external accessories for remote status or safety interlock circuits.
Current rating vs. ambient — no derating until 55 °C
This MCCB delivers its full 50 A rating from 40 °C through 50 °C ambient. At 55 °C it drops to 49 A, at 60 °C to 48 A, and at 70 °C to 45 A. That means in a typical 40 °C panel you get the full nameplate without headroom calculations. The rated insulation voltage is 800 V, so it's comfortable in 480 V and 600 V class systems.
Interrupting capacity across voltage levels
The interrupting capacity is specified at five voltage points: 75.6 kA at 240 V, 52.5 kA at 415 V, 32 kA at 440 V, and 11.9 kA at both 500 V and 690 V. For a 480 V system (common in North American industrial plants) the 32 kA at 440 V is the closest published figure — expect a similar value at 480 V. This gives solid selectivity headroom downstream of a larger feeder breaker.
Built-in auxiliaries and release
The breaker ships with two auxiliary switches and one trip alarm switch (HQ) factory-installed, plus an undervoltage release (UVR). That covers remote status monitoring and safety-related undervoltage trip without separate accessory orders. The UVR is wired to a control voltage — if that voltage drops, the breaker opens, which is standard for emergency-stop or power-loss sequences.
Physical footprint and operating range
Dimensions are 130 mm height, 76.2 mm width, 70 mm depth — a compact 3-pole MCCB footprint that fits standard panel mounting. Operating temperature range is -25 °C to 70 °C, storage from -40 °C to 80 °C. Maximum power loss at rated current is 17.1 W per pole, manageable in a ventilated enclosure.