The Siemens 3VA1112-5EF36-0AE0 is a SENTRON 3-pole molded case circuit breaker rated for line protection duty, carrying a TM240 thermal-magnetic overcurrent release and 125 A of continuous current at 40 °C through 50 °C ambient. Breaking capacity is the headline: 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at 690 V — that means this MCCB can safely interrupt fault currents up to those levels without welding contacts or cascading upstream, which is what you need for high-fault installations like transformer secondaries or large motor control centers.
Continuous current derating — where the 125 A rating holds and where it tapers
Above 50 °C the TM240 release begins to taper: 120 A at 55 °C, 117.5 A at 60 °C, 115 A at 65 °C, 112.5 A at 70 °C.
Panel fit — footprint and integration
The 3VA1112-5EF36-0AE0 measures 130 mm high, 76.2 mm wide, and 70 mm deep — a standard SENTRON 3VA frame size that drops into a DIN-rail or screw-mounted panel without surprises.