SENTRON 3VA1225-6EF42-0AH0 — 250 A Molded Case Circuit Breaker, 4-Pole, TM240 Release
The Siemens SENTRON 3VA1225-6EF42-0AH0 is a 4-pole molded case circuit breaker (MCCB) rated for line protection, carrying a continuous current of 250 A across its 40 °C to 50 °C ambient range — no derating needed up to that point (cites:,). Above 50 °C it derates linearly to 223 A at 70 °C (cites:,). The TM240 thermal-magnetic release provides fixed overload and short-circuit protection curves, with a trip indicator for visual fault confirmation (cites:,). Breaking capacity reaches 220 kA at 240 V AC, stepping down to 154 kA at 415 V, 75.6 kA at 440 V, 30 kA at 500 V, and 17 kA at 690 V — sufficient for high-fault utility feeds and transformer secondaries (cites:,). Rated insulation voltage is 800 V, giving headroom for 690 V line-to-line systems (cites:).
Panel Fit and Auxiliary Wiring
At 70 mm deep, 140 mm wide, and 158 mm tall, this MCCB occupies a standard SENTRON 3VA footprint — expect a 4-pole unit to span roughly 9 module widths on a DIN rail or direct-mount plate (cites:,). The auxiliary switch configuration is factory-fitted: two auxiliary contacts plus one trip alarm switch (HQ type), eliminating the need for a separate add-on module for basic status feedback (cites:). Power dissipation at rated load reaches 57 W maximum — factor that into enclosure thermal calculations, especially in sealed, high-fill panels (cites:). The breaker is designed without undervoltage release, ground-fault monitoring, or communication function, so those features must be added externally if required (cites:,).
Operating Environment and Storage
Rated for operation from -25 °C to 70 °C ambient, with storage range from -40 °C to 80 °C (cites:,). The storage limits exceed the operating range — that governs handling and warehousing, not running conditions. The thermal derating curve above 50 °C is the binding constraint for continuous load in warm enclosures.