MCCB for line protection — 400 A continuous, 4800 A frame
The Siemens SENTRON 3VA2440-5HN32-0BL0 is a 3-pole molded case circuit breaker (MCCB) designed for line protection — meaning it sits upstream of distribution or load feeders, interrupting faults before they propagate to downstream branch circuits. Rated 400 A continuously across the full 40 °C to 70 °C ambient range (no derating needed up to 70 °C), it carries a 4800 A frame that gives headroom for selectivity coordination with smaller downstream breakers. Short-circuit breaking capacity is voltage-dependent: 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 9 kA at 690 V. The 5 kA limited-to-1-second rating is the short-time withstand for selective coordination — the breaker can hold closed under fault for up to 1 s to let a downstream device clear first. The auxiliary switch complement is 2 auxiliary switches + 1 trip alarm switch + 1 electrical alarm switch HQ, and the undervoltage release (UVR) is built in. Maximum power loss is 66 W. Dimensions are 110 mm deep, 138 mm wide, 248 mm high — a standard SENTRON 3VA footprint for panel integration.