630 A MCCB with ETU320 — line protection for high-fault panels
The Siemens 3VA2463-7HL42-0AA0 is a 4-pole SENTRON molded case circuit breaker rated 630 A continuous at 40 °C, fitted with an ETU320 electronic trip unit. It is designed for line protection in distribution panels where fault currents can reach 330 kA at 240 V or 242 kA at 415 V — common in industrial mains and transformer secondaries. The 4-pole configuration covers three-phase plus neutral, so it suits TN-S or TN-C-S systems where the neutral needs overcurrent protection.
Breaking capacity and thermal derating — what the ratings mean for fit
The 330 kA at 240 V and 242 kA at 415 V are the ultimate short-circuit breaking capacities (Icu) — the breaker clears those fault levels once and remains functional. At 690 V it drops to 9 kA, so verify the line-to-line voltage on the secondary side. The continuous current derates with ambient temperature: 630 A at 40 °C, 612 A at 45 °C, 593 A at 50 °C, 575 A at 55 °C, 557 A at 60 °C, 538 A at 65 °C, and 520 A at 70 °C. If the panel ambient runs above 40 °C, size the breaker for the derated figure — the ETU320 electronic trip compensates thermally, but the frame rating is the hard limit.
Mounting dimensions and panel integration
The breaker measures 248 mm high, 184 mm wide, and 110 mm deep. It mounts on a DIN rail or directly to a backplate via the screw terminals. The 184 mm width for a 4-pole frame means it occupies roughly 7.24 inches of DIN space — account for that when laying out the gland plate and busbar takeoffs. IP40 on the front protects against tools and solid objects larger than 1 mm; the enclosure sides and rear are open to the panel interior, so the overall panel IP rating governs.