The Siemens SENTRON 3VA1225-6GF42-0AG0 is a 4-pole molded case circuit breaker rated at 250 A continuous, with a TM240 thermal-magnetic overcurrent release. That TM240 designation means the thermal pickup is fixed at 240 A, so this breaker is sized for a 240 A nominal load path — not a general-purpose 250 A frame you can adjust down. The insulation voltage is rated at 800 V, which covers 480 V and 600 V class systems with headroom. Breaking capacity is what you check first for fault coordination. At 240 V this breaker interrupts 220 kA; at 415 V it's 154 kA; at 440 V it drops to 75.6 kA; at 500 V it's 30 kA; and at 690 V it's 17 kA. Thermal derating matters for panel ambient. The breaker carries a full 250 A at 40 °C through 50 °C. At 55 °C it's 243 A; at 60 °C it's 237 A; at 65 °C it's 230 A; at 70 °C it's 223 A. If your enclosure runs hot — say a packed MCC lineup — that 223 A at 70 °C is the number to size against, not the 250 A sticker. That gives you one N/O or N/C signal for breaker position and one dedicated signal that only changes state on a trip event — useful for remote fault annunciation without wiring through the position contact.
Lifecycle and compliance — active line, no obsolescence concern
Operating temperature range is -25 °C to 70 °C, with storage from -40 °C to 80 °C. The storage range exceeds the operating range — that's for shipping and warehousing, not running.
The breaker measures 140 mm wide, 158 mm high, and 70 mm deep.