What it is and what it does
The Siemens 3VA1125-3EF32-0AF0 is a SENTRON molded case circuit breaker (MCCB) for line protection — the main disconnect and fault interruption in a distribution panel or motor control center. Three poles, rated 25 A continuous at 40 °C ambient, with a TM240 thermal-magnetic overcurrent release that handles both overload and short-circuit trips without external control power. Breaking capacity of 75.6 kA at 240 V AC means it can safely interrupt a fault current up to that level — enough for high-available-fault service entrances or industrial switchgear without cascading upstream breakers. Rated insulation voltage of 800 V. Power loss is 8.5 W maximum.
Auxiliary switching and monitoring
Factory-fitted with one auxiliary switch and one trip alarm switch (HQ configuration) — the trip alarm signals when the breaker has opened on a fault, separate from the manual ON/OFF position. Trip indicator visible on the front. No undervoltage release, no ground-fault monitoring, no communication module on this variant — it is a straight thermal-magnetic line protection breaker.
Dimensions and panel fit
Width 76.2 mm (3 in), height 130 mm (5.12 in), depth 70 mm (2.76 in). Standard 3-pole MCCB footprint for DIN-rail or panel-mount installation in a distribution board.