What this MCCB carries and where it fits
The Siemens 3VA1225-5EF32-0AD0 is a SENTRON molded case circuit breaker (MCCB) rated for 250 A continuous current on a 3-pole frame, fitted with a TM240 thermal-magnetic overcurrent release. It's built for line protection — meaning it sits upstream protecting a feeder or a distribution bus, not a specific motor load. The interrupting ratings tell you where it can go: 187 kA at 240 V, 121 kA at 415 V, 36 kA at 440 V, and 17 kA at 690 V. Those numbers cover most industrial service entrances and sub-distribution boards in North America (240/480 V) and Europe (400/690 V) without needing a current-limiting fuse upstream. It's a current-production part, so you're not hunting surplus bins — this is the active catalog line.
Thermal curve and panel fit
The TM240 release holds 250 A straight up to 50 °C ambient, then starts a gentle derate: 243.3 A at 55 °C, 236.5 A at 60 °C, 229 A at 65 °C, and 223 A at 70 °C. If your panel runs hot — say a packed MCC lineup near a furnace line — that 223 A floor at 70 °C is the number to size your downstream load against, not the 250 A nameplate. The 105 mm width, 158 mm height, and 70 mm depth put it in the standard 3VA frame footprint. It'll bolt into a SENTRON panelboard or a DIN-rail adapter without re-drilling the backpan.
Auxiliary contacts and enclosure sealing
It ships with three HQ auxiliary switches — those are the high-reliability contacts for signaling the breaker position back to a PLC or a status lamp. No undervoltage release, no shunt trip, no ground-fault module on this variant; those are add-on accessories if your circuit needs them. IP40 on the front means it's splash-proof from the panel face but not hose-down rated. Fine for a dry indoor MCC room; don't put it in a washdown zone without an enclosure over it.
Sourcing and compliance
The 800 V rated insulation voltage (Ui) and the interrupting ratings across the voltage range mean it carries the usual IEC 60947-2 and likely UL 489 certifications for the class — standard compliance documentation (CE, UKCA, RoHS, REACH) is provided with the shipment.