The Siemens 3VA1225-5EF42-0KH0 is a 4-pole SENTRON molded case circuit breaker rated for 250 A continuous current. It's the line protection variant — meaning it's set up to guard feeders and main branch circuits, not motor loads. The TM240 thermal-magnetic trip unit handles overload and short-circuit response, no electronics to configure. Breaking capacity hits 187 kA at 240 V, dropping to 121 kA at 415 V and 36 kA at 440 V — numbers that matter if you're sizing it for a high-fault panel downstream of a large transformer.
Physical footprint: 70 mm deep, 140 mm wide, 158 mm tall. That's a standard SENTRON 3VA frame size — it'll drop into the existing panel cutout if you're swapping a same-generation SENTRON breaker. Front face carries IP40 protection, so it's fine for a clean indoor enclosure but not washdown zones. The auxiliary contact block is already fitted: 2 auxiliary switches plus a separate trip alarm switch, all HQ type. That means you get independent status feedback on the breaker position AND a dedicated signal for trip events — useful for a PLC input without extra wiring.
Compared to the smaller-frame 3VA1010-2ED32-0JA0, this 3VA1225 is a different animal — the 1010 tops out at 100 A and 3 poles. The 1225 carries 250 A, 4 poles, and a much higher interrupting rating (187 kA vs something under 100 kA at 240 V). No direct drop-in without rewiring; the frame size, bus connections, and lug kits are different. If you're looking for a 250 A 4-pole SENTRON with thermal-magnetic trip, this is the one.