What this MCCB carries and where it fits
The Siemens 3VA1150-5EF36-0CH0 is a 3-pole SENTRON molded case circuit breaker rated for 50 A continuous current (Iu) with a TM240 thermal-magnetic overcurrent release. It's designed for line protection — meaning it sits upstream of distribution or load feeders, not as a motor-protective device with phase-failure detection. The interrupting ratings climb to 187 kA at 240 V and 121 kA at 415 V, so it handles high-fault-capacity utility feeds or transformer secondaries where the available fault current is substantial. The 76.2 mm width and 70 mm depth keep it within a standard MCCB footprint on a DIN rail or panel-mount base.
Thermal derating and what the 50 A means in a warm panel
The 50 A rating holds flat from 40 °C to 50 °C ambient — no derating needed in most enclosed panels. Above that it drops: 48 A at 55 °C, 47 A at 60 °C, 46 A at 65 °C, and 45 A at 70 °C. If your panel interior runs hot (say, next to a VFD bank or transformer), the continuous load must be trimmed accordingly. The TM240 release is a fixed thermal-magnetic type; no interchangeable trip units, so the breaker is sized at order time for the 50 A frame.
Auxiliary contacts and undervoltage release
This variant ships with two auxiliary switches and one trip-alarm switch (HQ type) as standard, plus an integrated undervoltage release (UVR). The UVR coil is listed under order code 3VA9608-0BB24 — if you're replacing a unit in a safety circuit that drops the breaker on undervoltage, verify the coil matches your control voltage. The auxiliary contacts give remote status: one for the main contact position, one for the trip-alarm flag. No communication module or ground-fault monitoring is built in; this is a straightforward protective breaker, not a metering device.