The Siemens SENTRON 3VA1150-6EF32-0AF0 is a 3-pole molded case circuit breaker (MCCB) with a TM240 thermal-magnetic release, rated 50 A at 40 °C and carrying a 220 kA interrupting capacity at 240 V AC. That 220 kA rating at 240 V means it handles very high fault currents typical of large transformer-fed distribution — the sort of fault level that would weld a standard MCB's contacts shut. At 415 V it still interrupts 154 kA, and at 690 V it holds 17 kA, so it's sized for main or sub-feed protection in industrial switchgear, not just branch circuits.
Thermal derating and panel fit
The breaker is rated a full 50 A from 40 °C up to 50 °C ambient, then derates linearly to 45 A at 70 °C. That means in a crowded panel running at 55 °C you lose only 1 A — negligible for most designs. The 70 mm depth by 76.2 mm width footprint is standard for SENTRON 3VA fixed-thermal breakers; it snaps onto DIN rail or mounts directly to a backplate. The 14.6 W maximum power loss at rated load is modest — no forced ventilation needed in a typical enclosure at that dissipation.
What the ratings mean for your panel
The TM240 release is a thermal-magnetic trip with a 240 A frame — the 50 A continuous rating is set by the installed thermal element, not the frame size. That gives headroom: the same breaker platform can be ordered with higher amp ratings up to the 240 A frame limit. Rated insulation voltage is 800 V, so it's comfortable on 480 V or 600 V class systems even though the interrupting ratings are specified at several voltage points. The -25 °C to +70 °C operating range covers most indoor industrial environments; storage from -40 °C to +80 °C handles warehouse or shipping extremes.