Siemens SENTRON 3VA2463-6JQ32-0AJ0 — 630 A MCCB for Line Protection
The Siemens SENTRON 3VA2463-6JQ32-0AJ0 is a 3-pole molded case circuit breaker (MCCB) rated for 630 A at 40 °C, designed for line protection in distribution panels and industrial switchboards. Its 242 kA interrupting capacity at 240 V AC handles high-fault scenarios typical of large transformer-fed services, while the 187 kA at 415 V and 121 kA at 500 V cover medium-voltage step-down applications. The electronic trip unit offers an adjustable current range from 945 A minimum to 5670 A maximum, with a full-scale value of 630 A — meaning the breaker can be set to protect feeders or main buses within that band. A built-in communication function allows integration with energy management or SCADA systems, and the trip indicator provides local fault visibility without opening the panel door.
Thermal Derating and Power Loss
Continuous current derates from 630 A at 40 °C ambient to 450 A at 70 °C — a drop of roughly 3 A per degree above 40 °C — so panel internal temperature rise must be factored into the breaker's actual load capacity. Maximum power loss is 162 W at rated current, which contributes to enclosure heat load and should be included in the panel thermal budget. The breaker occupies 138 mm width, 248 mm height, and 110 mm depth — a standard 3-pole MCCB footprint that fits most Siemens SENTRON switchboard mounting bases without adapter plates.