What this MCCB is and what it protects
The Siemens 3VM1150-3ED12-0AA0 is a 1-pole SENTRON molded case circuit breaker (MCCB) designed for line protection — it sits upstream of a load, typically a feeder or branch circuit, and clears faults before they damage downstream wiring or equipment. Its TM210 thermal-magnetic release means the thermal element handles overloads (inverse-time curve) and the magnetic element handles short-circuits (instantaneous trip). The 50 A continuous rating holds up to 50 °C without derating; at 55 °C it's 49 A, at 60 °C it's 48 A, at 65 °C it's 46 A, and at 70 °C it's 45 A — so in a warm panel you lose 5 A by the time you hit 70 °C ambient. Interrupting capacity is 53 kA at 240 V AC and 8 kA at 415 V AC — the 415 V figure is the one to watch for three-phase line-to-line faults in a 400 V system; 8 kA is modest, so verify the available fault current at the installation point. The 53 kA at 240 V covers single-phase or line-to-neutral faults comfortably.
Mounting and panel fit
At 25.4 mm wide (1 inch), this single-pole MCCB snaps onto a DIN rail. Depth is 70 mm (2.76 in), height 130 mm (5.12 in). No trip indicator, no undervoltage release, no communication function — this is a bare thermal-magnetic MCCB with no auxiliaries. If you need remote signaling or undervoltage protection, you'll add external modules or step up to a 3VA-series frame that supports those accessories.
Lifecycle and sourcing reality
Maximum power loss is 5 W — negligible for panel thermal budgeting, but worth noting if you're packing many breakers into a sealed enclosure. Insulation voltage rated at 500 V, operating voltage up to 415 V AC or 125 V DC. Storage range is -40 °C to 80 °C; operating range is -25 °C to 70 °C.