Siemens 3VA1112-3ED32-0AA0 — 125 A MCCB with TM210 trip, line protection duty
The Siemens 3VA1112-3ED32-0AA0 is a SENTRON molded case circuit breaker (MCCB) rated 125 A continuous at 40 °C, with a TM210 thermal-magnetic overcurrent release and 3 poles for three-phase line protection. It carries a breaking capacity of 75.6 kA at 240 V AC, 52.5 kA at 415 V AC, and 32 kA at 440 V AC, so it handles high-fault scenarios typical of industrial distribution panels without cascading upstream. The TM210 trip unit provides fixed thermal and magnetic settings — no adjustment dials — which keeps the part simple for a fixed-load BOM line where the engineer already knows the cable and load current.
Thermal derating and ambient temperature profile
At 55 °C it derates to 122 A, at 60 °C to 120 A, at 65 °C to 117 A, and at 70 °C to 114 A. That's a gentle slope — about 0.6 A per degree above 50 °C — so a panel running at 60 °C ambient still carries 120 A continuous.
Mounting dimensions and panel fit
The breaker measures 130 mm high, 76.2 mm wide, and 70 mm deep — a standard 3-pole MCCB footprint for DIN-rail or screw-mount panel integration. Width of 76.2 mm (3 inches) matches the typical 3-pole SENTRON slot; depth of 70 mm means it clears most 200 mm deep enclosures with room for wiring gutters.