What this MCCB does on the line
The Siemens 3VA2225-7HL32-0KA0 is a SENTRON molded case circuit breaker rated 250 A continuous current on a 3-pole frame, designed for line protection in distribution panels and motor control centers. Its interrupting capacity hits 330 kA at 240 V and 242 kA at 415 V — that is the fault-clearing headroom you need for high-available-fault-current installations like transformer secondaries or large busway feeds. At 690 V the rating drops to 4.5 kA, so this is a 400 V class breaker, not a 690 V main. The shunt trip release (STL) on this variant lets a remote signal — from an emergency-stop circuit, a fire-alarm relay, or a PLC safety output — trip the breaker open. That makes it a fit for applications where you need remote disconnect capability without running a separate contactor.
Thermal derating — the real ampacity
The breaker holds its full 250 A rating up to 50 °C ambient. At 55 °C it derates to 241 A, at 60 °C to 232 A, at 65 °C to 222 A, and at 70 °C to 213 A. If your panel ambient runs above 50 °C — say a packed enclosure near a furnace line or a solar combiner — size the breaker for the derated value, not the nameplate. Maximum operating temperature is 70 °C; storage range is -40 to 80 °C.
Panel fit and mounting
Dimensions are 86 mm deep, 105 mm wide, 181 mm tall. It mounts on a DIN rail or bolts directly into a panel backplate. The 3-pole footprint matches standard SENTRON 3VA2 cutouts; if you are replacing a 3VA1 frame, check the depth — the 3VA2 is deeper by roughly 10 mm. Maximum power loss is 48 W, so factor that into your enclosure thermal budget.