What this 630 A MCCB carries — and where it fits
The Siemens SENTRON 3VA2463-6JP42-0AA0 is a 4-pole molded case circuit breaker rated for 630 A continuous current at 40 °C, fitted with an ETU550 electronic trip unit. This is a line-protection design — meaning it's sized for main feeder or large sub-distribution duty, not motor branch circuit protection. The 4-pole configuration covers three-phase plus neutral, common in North American and IEC panels where the neutral needs overcurrent protection or isolation. Breaking capacity is substantial: 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 9 kA at 690 V. At 690 V the rating drops sharply — this breaker is optimized for low-voltage distribution up to 500 V, not 690 V main service. The 242 kA at 240 V covers high-fault utility feeds in North American panels. The ETU550 is a programmable electronic trip unit with LSI (long-time, short-time, instantaneous) protection curves and communication capability. The communication function means it can integrate with a building management or power monitoring system via the SENTRON communication modules — useful for energy management or remote trip indication in critical feeders.
Temperature derating — real-world current capacity
The 630 A rating is at 40 °C ambient. Above that, the breaker must be derated: 600 A at 45 °C, 570 A at 50 °C, 540 A at 55 °C, 510 A at 60 °C, 480 A at 65 °C, and 450 A at 70 °C. If this breaker sits in a hot enclosure or near other heat sources, the actual continuous current it can carry drops significantly. For a 630 A feeder in a 50 °C panel, plan for 570 A maximum without nuisance tripping. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. The power loss at full rated current is 162 W maximum — factor that into enclosure ventilation if the panel is sealed or has multiple breakers.
Mounting dimensions and panel fit
Dimensions: 248 mm high, 184 mm wide, 110 mm deep. The 184 mm width is for a 4-pole frame.