630 A MCCB with ETU850 — line protection for main feeders
The Siemens 3VA2463-6KP32-0DL0 is a SENTRON 3VA2 molded case circuit breaker (MCCB) sized for main feeder or large branch protection. Rated continuous current Iu is 630 A at 40 °C, with a published derating curve that drops to 450 A at 70 °C — critical for panels running near the thermal limit. The ETU850 electronic trip unit gives adjustable long-time, short-time, instantaneous, and ground-fault (via external module) protection curves, making it a fit for coordinated selective schemes in industrial distribution. Interrupting capacity is voltage-dependent: 242 kA at 240 V AC, 187 kA at 415/440 V, 121 kA at 500 V, and 40 kA at 690 V. At 690 V the 40 kA rating still covers most transformer-fed fault levels in 690 V mining or marine distribution. The 3-pole construction and rated insulation voltage of 800 V suit solidly-grounded or impedance-grounded systems up to 690 V line-to-line. Auxiliary contact block ships as part of the order code: 2 auxiliary switches, 1 trip alarm switch, and 1 electrical alarm switch (HQ type). The integrated undervoltage release (UVR) is factory-installed — no field wiring of a separate shunt trip. Communication function is present on this variant, allowing integration into a higher-level monitoring or SCADA system.
Physical fit — panel cutout and mounting
Power loss at rated current is 164.5 W maximum — account for this in enclosure thermal calculations, especially when grouping multiple breakers in a sealed cabinet. Ambient derating is already captured in the continuous current table; no additional margin needed if the enclosure ambient stays below 40 °C.