The Siemens 5SY4225-7CV is a 2-pole miniature circuit breaker (MCB) with a C-curve trip characteristic rated at 25 A. Its interrupting capacity is 15 kA at 400 V AC, which means it can safely clear a bolted fault up to that level without welding contacts or cascading failure upstream — a critical spec for high-fault-capacity industrial panels where the available short-circuit current exceeds the typical 6 kA or 10 kA domestic-grade MCB.
The 15 kA rating at 400 V makes it suitable for installation downstream of a transformer or in an industrial MCC where fault levels are higher than a residential service entrance.