What this MCCB carries — and what that means for your panel
The Siemens 3VA2225-7HL32-0DH0 is a SENTRON molded case circuit breaker (MCCB) rated for 250 A continuous current at 40 °C, with an ETU320 electronic trip unit. That 250 A holds flat through 50 °C — you only start derating above 55 °C, where it drops to 241 A, then 232 A at 60 °C, 222 A at 65 °C, and 213 A at 70 °C. So for most panel environments under 55 °C, you get the full 250 A without having to oversize the frame. Breaking capacity is the headline here: 330 kA at 240 V, 242 kA at 415 V and 440 V, 187 kA at 500 V, and 6.3 kA at 690 V. That 330 kA at 240 V means it can interrupt a fault current up to that level without upstream devices needing to coordinate — useful on high-capacity transformer secondaries or busway taps where available fault current is high. It's a 3-pole unit (Line protection version) with an undervoltage release (UVR) built in — part of the supplied basic switch 3VA2225-7HL32-0AA0 and integrated auxiliary trip 3VA9608-0BB25. The auxiliary contact configuration is 2 auxiliary switches plus 1 trip alarm switch (HQ type), which gives you status feedback for PLC or SCADA without adding external relays.
Physical fit and panel integration
Dimensions: 105 mm wide, 181 mm tall, 86 mm deep. Rated insulation voltage Ui is 800 V, and operating temperature range is -25 °C to 70 °C, with storage from -40 °C to 80 °C. Maximum power loss at rated current is 50.5 W — that's the heat you need to vent from the enclosure; if you're packing multiple breakers in a sealed box, derate or add forced ventilation. Mechanical endurance is 20,000 operations (latching endurance).