What it is and what the ratings mean
The Siemens SENTRON 3VA2225-5JQ32-0JC0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection, carrying a full-scale current of 250 A and a minimum setting of 375 A. Its interrupting ratings are the key fit decision: 187 kA at 240 V, 121 kA at 415 V and at 440 V, 75.6 kA at 500 V, and 4.5 kA at 690 V. The 187 kA at 240 V means it can safely clear a fault current up to that level without the arc flashing over or the breaker failing — critical for high-fault panels near large transformers. The steep drop to 4.5 kA at 690 V tells you this is a 240–500 V class breaker; at 690 V it is only for low-fault installations. Thermal derating is built in: the breaker carries a full 250 A from 40 °C through 50 °C, then steps down to 238 A at 55 °C, 225 A at 60 °C, 213 A at 65 °C, and 200 A at 70 °C. If your panel ambient sits at 55 °C, you lose 12 A of headroom — plan the load accordingly. Maximum power loss is 48 W at rated current, which matters for enclosure heat calculations. This MCCB includes a communication function and a shunt trip (STL) release, plus two HQ auxiliary switches. The shunt trip allows remote tripping from a PLC or emergency-stop circuit. There is no undervoltage release on this variant. The basic switch module is order code 3VA2225-5JQ32-0AA0.
Mounting and panel fit
Dimensions: 105 mm wide, 181 mm high, 86 mm deep. The 105 mm width is the standard 3-pole MCCB footprint for this class — it fits existing SENTRON mounting plates and busbar systems without adapters. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C.