The Siemens SENTRON 3VA1112-6ED46-0AA0 is a 4-pole molded case circuit breaker (MCCB) in the line-protection version, rated for 125 A continuous current at 40 °C and fitted with a TM210 thermal-magnetic overcurrent release. It handles fault currents up to 220 kA at 240 V AC, dropping to 154 kA at 415 V and 76 kA at 440 V — numbers that tell you it's sized for high-available-fault-current distribution panels, not branch circuits.
The 125 A rating holds flat from 40 °C to 50 °C, then derates to 122 A at 55 °C, 120 A at 60 °C, 117 A at 65 °C, and 114 A at 70 °C. Breaking capacity is voltage-dependent: 220 kA at 240 V, 154 kA at 415 V, 76 kA at 440 V, and 17 kA at both 500 V and 690 V. The 240 V figure is extreme — that's a utility-grade fault level. At 690 V the 17 kA is modest; verify your system's prospective short-circuit current at that voltage before committing the BOM line. The TM210 release is thermal-magnetic — no electronic adjustment, no ground-fault monitoring, no communication.
Footprint is 101.6 mm wide by 130 mm tall by 70 mm deep — a 4-inch-wide body that occupies four pole spaces on a DIN-rail or panel-mount base.