What this 3VA MCCB brings to the panel
The Siemens SENTRON 3VA1112-6EF36-0AA0 is a 3-pole molded case circuit breaker rated for line protection, carrying a continuous current of 125 A up to 50 °C with no derating needed — above that it steps down to 122 A at 55 °C, 120 A at 60 °C, 117 A at 65 °C, and 114 A at 70 °C, so in a warm enclosure you still have headroom for a full 125 A bus if the ambient stays under 50 °C. The TM240 thermal-magnetic release handles the overload and short-circuit curve. Insulation voltage is rated 800 V. Breaking capacity runs 220 kA at 240 V, 154 kA at 415 V, 75.6 kA at 440 V, and 17 kA at both 500 V and 690 V — that 220 kA figure at 240 V tells you this breaker is sized for high-fault industrial panels, not light commercial. Front IP40 protection means it's fine inside a clean enclosure; not rated for washdown zones.
Panel fit and dimensions
The breaker measures 130 mm high, 76.2 mm wide, and 70 mm deep — the 3-pole width is a standard 3-inch (76.2 mm) footprint, so it drops into existing SENTRON or 3VA panel cutouts without re-drilling. Max power loss is 28.1 W, which matters for thermal budgeting inside a sealed enclosure — not a high-loss unit, but worth factoring into the cabinet cooling calc if you're stacking several breakers.