What it is and what it does
The Siemens SENTRON 3VM1220-4EE42-0AA0 is a 4-pole molded case circuit breaker (MCCB) rated 200 A continuous at 40 °C, carrying the TM220 thermal-magnetic trip unit. It's line protection — no ground-fault monitoring, no communication module, no motor drive add-on. Straight overcurrent and short-circuit protection for distribution panels, feeder circuits, and main disconnects where you need a clean, no-frills MCCB. Breaking capacity runs 121 kA at 240 V AC, 76 kA at 415 V, 53 kA at 440 V, and 17 kA at 500 V — that's serious fault-current headroom for industrial mains. At 690 V rated insulation voltage (Ui), it's built for 400 V and 480 V distribution without derating the insulation.
Thermal derating and panel fit
Full 200 A holds through 50 °C ambient. Above that it steps down: 194 A at 55 °C, 188 A at 60 °C, 182 A at 65 °C, 176 A at 70 °C. If your panel runs hot — say a packed enclosure near a furnace line — that derating curve is your real ampacity limit, not the nameplate. Power loss maxes at 42 W, so factor that into your enclosure thermal budget. Dimensions: 158 mm tall, 140 mm wide, 70 mm deep. IP40 on the front — protected against tools and wires, not washdown. Mounts in a standard distribution panel or switchboard; no DIN-rail clip on this frame size, it bolts in.