The Siemens SENTRON 3VA1112-6MH36-0BC0 is a 3-pole molded case circuit breaker (MCCB) rated for 125 A continuous current at 40 °C ambient, with a breaking capacity of 220 kA at 240 V AC and 154 kA at 415 V AC. It is designed specifically for starter protection — meaning it's built to handle the high inrush and short-circuit stresses of motor-starting applications, not just general distribution.
The 125 A rating holds flat from 40 °C to 50 °C, then derates gradually: 122 A at 55 °C, 120 A at 60 °C, 117 A at 65 °C, and 114 A at 70 °C. The 800 V rated insulation voltage (Ui) means it's safe for 690 V line-to-line systems, and the 7.5 kA breaking capacity at 690 V confirms it can clear a fault on a 690 V motor circuit, though at a much lower level than the 240 V or 415 V ratings. Power dissipation is 30.6 W maximum — not negligible in a sealed panel.
This MCCB mounts on a DIN rail (standard 35 mm profile) or can be screw-fixed to a backplate. Dimensions are 130 mm height, 76.2 mm width, and 70 mm depth — a 3-pole footprint that fits most panel layouts without surprises. The 3-pole design handles three-phase motor loads, and the integrated auxiliary switches (2 HQ contacts) give you a spare NO/NC pair for PLC feedback or alarm annunciation without adding a side-mount block.