The Siemens SENTRON 3VA1220-5EF42-0AA0 is a 4-pole molded case circuit breaker (MCCB) rated 200 A continuous at 40 °C, with a TM240 thermal-magnetic trip unit. It's a line-protection design — meaning it's built for feeder and distribution circuits, not motor-starting duty — and carries a 187 kA interrupting rating at 240 V AC, which drops to 121 kA at 415 V and 75.6 kA at 440 V. That kind of headroom handles high-fault utility feeds or transformer secondaries without cascading upstream.
Ratings and what they mean for the panel
The 200 A rating holds flat from 40 °C to 50 °C — no derating needed in a warm enclosure. At 55 °C it's 194 A, at 60 °C it's 188 A, and at 70 °C it's 176 A. That's a clean thermal curve; you can size the breaker at 200 A and still have margin in a typical 50 °C panel interior. Breaking capacity spans the voltage range: 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, 30 kA at 500 V, and 17 kA at 690 V. For a 480 V distribution panel, the 75.6 kA at 440 V is the closest published figure — that's well above typical 25–65 kA SCCR requirements for commercial gear. The TM240 release is a thermal-magnetic type, so it gives inverse-time overload protection plus instantaneous magnetic trip for short circuits. Rated insulation voltage is 800 V, and the front face carries IP40 protection — fine for enclosed panel mounting, not for washdown. Max power loss is 42 W, which matters for thermal budgeting in a densely packed lineup. Ambient operating range is -25 °C to 70 °C; storage range is -40 °C to 80 °C.
The 3VA1220-5EF42-0AA0 measures 140 mm wide, 158 mm high, and 70 mm deep. It's a panel-mount MCCB — no DIN-rail clip, so it bolts into a cutout or mounts on a backplate. Four poles means it switches all three phases plus neutral, which is standard for a 4-wire distribution feeder. No undervoltage release, no communication module, no ground-fault monitoring on this variant — it's a straight thermal-magnetic breaker for basic overcurrent protection.