What this MCCB is and what it protects
The Siemens SENTRON 3VA2225-5KP32-0AB0 is a 3-pole molded case circuit breaker rated for 250 A continuous current, designed for line protection in distribution panels. It carries a maximum interrupting capacity of 187 kA at 240 V and 121 kA at 415 V, so it can clear high-fault currents without upstream coordination issues in most industrial service-entrance or feeder applications.
Current ratings and thermal derating
The breaker holds its full 250 A rating from 40 °C up to 50 °C ambient. Above that, it derates linearly: 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 runs hot — say, next to a drive cabinet — size the load side for the derated figure at your actual enclosure temperature, not the nameplate 250 A.
Interrupting performance across voltages
Breaking capacity drops as system voltage rises: 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 4.5 kA at 690 V. For a 480 V delta or 400 V wye service, the 121 kA figure covers most utility transformer sizes. At 690 V the 4.5 kA limit means this breaker is only suitable for low-fault installations or where upstream current-limiting fuses are used.
Dimensions and panel fit
The breaker measures 105 mm wide, 181 mm tall, and 86 mm deep. That 105 mm width is a standard 3-pole MCCB footprint for this class — it fits a typical 200–250 A panelboard or switchboard cubicle without special adapters. The 86 mm depth includes the arc chamber and line-side lugs; allow clearance for cable bending radius below the breaker.