The Siemens SENTRON 3VA1112-6EF32-0DC0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection, carrying a continuous current of 125 A at 40 °C and a rated insulation voltage of 800 V. Its interrupting capacity sits at 220 kA at 240 V, 154 kA at 415 V, 75.6 kA at 440 V, and 17 kA at 500/690 V — that's the short-circuit current it can safely clear at each voltage level without welding or rupturing, which governs your panel's SCCR coordination downstream.
Thermal derating and auxiliary fit
The breaker holds its full 125 A rating up to 50 °C ambient, then derates to 122 A at 55 °C, 120 A at 60 °C, 117 A at 65 °C, and 114 A at 70 °C.