What this MCCB carries — and where it fits
The Siemens 3VA1220-6MH32-0AA0 is a SENTRON molded case circuit breaker rated for 200 A continuous at 40 °C, with a TM120M thermal-magnetic trip unit that handles both overload and short-circuit protection in a single device. It's a 3-pole frame designed for starter protection — meaning it's sized to sit ahead of a motor starter or as a feeder breaker in a distribution panel, not as a branch device protecting a final load directly. The interrupting capacity drops as voltage climbs: 220 kA at 240 V, 154 kA at 415 V, 75.6 kA at 440 V, 30 kA at 500 V, and 4.5 kA at 690 V — so the application voltage determines whether this frame has headroom for high-fault installations or is tight for a 690 V bus. Rated insulation voltage is 800 V, which covers most LV industrial networks.
Thermal derating — the real continuous current
The 200 A rating holds flat from 40 °C to 50 °C. Above that it derates: 194 A at 55 °C, 188 A at 60 °C, 182 A at 65 °C, 176 A at 70 °C. If the panel ambient runs hot — say next to a drive cabinet or in a non-conditioned enclosure — the actual continuous current you can pull is lower than the nameplate. Plan the load accordingly.
Panel fit and mounting
The 3VA1220-6MH32-0AA0 measures 105 mm wide, 158 mm high, and 70 mm deep — a standard 3-pole MCCB footprint that drops into a SENTRON distribution board or a DIN-rail adapter plate. IP40 on the front means it's protected against tools and small wires entering the face, but not sealed against washdown; keep it inside the enclosure. Power loss at full load is 42 W — account for that in the enclosure thermal budget.