The SENTRON 3VA1112-6EF32-0AF0 is a 3-pole molded case circuit breaker rated for 125 A continuous current (Iu) at up to 40 °C, carrying a TM240 thermal-magnetic overcurrent release. Its interrupting capacity at 240 V reaches 220 kA, dropping to 154 kA at 415 V, 75.6 kA at 440 V, and 17 kA at 690 V — figures that tell you the available fault current this breaker can safely clear without upstream coordination failure.
The 125 A rating holds up to 50 °C ambient (–); above that, the thermal curve begins a gradual derate — 120 A at 55 °C, 117.5 A at 60 °C, 115 A at 65 °C, 112.5 A at 70 °C (–). If your panel internal ambient exceeds 50 °C, the effective continuous capacity drops, so size the upstream feeder and bus accordingly. The TM240 release is a fixed thermal-magnetic design — no electronic adjustment, no communication, no ground-fault module. That keeps the part simple and reliable for straightforward line-protection duty where you don't need selective coordination curves or remote monitoring. That's useful for a PLC or SCADA input that distinguishes a manual open from a fault.