The Siemens SENTRON 3VA1125-5EF36-0KC0 is a 3-pole molded case circuit breaker (MCCB) rated for 25 A continuous current at 40 °C, with a TM240 thermal-magnetic release that provides both overload and short-circuit protection in a single device. Its interrupting capacity reaches 187 kA at 240 V AC, 121 kA at 415 V, and 75.6 kA at 440 V — figures that give you selectivity headroom in high-fault panels without cascading upstream breakers.
Breaking capacity and thermal derating — the real selection numbers
The 187 kA at 240 V is the headline, but the 121 kA at 415 V and 75.6 kA at 440 V are what matter for most 400 V-class industrial panels. The thermal derating curve is flat from 40 °C to 50 °C (full 25 A), then steps down: 24 A at 55 °C, 23.5 A at 60 °C, 23 A at 65 °C, and 22.5 A at 70 °C.
Panel integration and auxiliary options
The 3VA1125-5EF36-0KC0 includes a factory-fitted shunt trip (STL) release (order code 3VA9688-0BL33) and two auxiliary switches (HQ type). The shunt trip allows remote tripping from a PLC or emergency-stop circuit — verify the coil voltage matches your control supply. Front IP40 protection is standard for clean indoor panels; no washdown rating.