What this MCCB brings to the panel
The Siemens SENTRON 3VA1220-6EF42-0AA0 is a 4-pole molded case circuit breaker rated for 200 A continuous (Iu) with a TM240 thermal-magnetic overload release, built for line-protection duty in distribution panels. At 240 V it interrupts 220 kA — that is serious fault-current headroom for high-capacity mains or subfeeds where upstream coordination demands a high SCCR. The 800 V rated insulation voltage (Ui) covers most industrial voltages up to 690 V phase-to-phase. At 415 V the breaking capacity is still 154 kA, and it tapers to 17 kA at 690 V — so it stays usable on 400 V-class systems without a second tier of current-limiting fuses.
Ratings that drive the choice
The 200 A continuous rating holds steady from 40 °C up to 50 °C — no derating needed in a warm enclosure at those ambient temperatures. At 55 °C it derates to 194 A, at 60 °C to 188 A, and at 70 °C to 176 A. If the panel sits near a heat source or in a hot plant, that derating curve tells you whether this frame size still works or you need to step up to the next amp rating. The TM240 release means the thermal element is calibrated for a 200 A frame with a 240 A fixed magnetic pickup — typical for protecting cables or busbars against overloads while clearing high-impedance faults fast. Power loss is 42 W maximum at rated current — that is heat that stays inside the enclosure. Factor it into the thermal budget, especially if the panel is densely packed or the ambient is already at the derating threshold. The front face is IP40, so it is protected against tools and wires larger than 1 mm but not against water ingress; keep it behind a sealed door if the environment is wet.
Dimensions and panel fit
The 3VA1220-6EF42-0AA0 measures 140 mm wide, 158 mm high, and 70 mm deep. That 70 mm depth is shallow enough for most standard distribution boards and motor control centers — no deep-can requirement. The 140 mm width is a 4-pole frame, so it occupies four module widths on a DIN rail or bolted busbar mount. Verify the busbar spacing and the mounting footprint against your existing panel layout; the SENTRON 3VA family uses a common bolt pattern across the frame sizes, so swapping within the family usually avoids drilling new holes.