63 A MCCB with ETU850 — what the ratings mean for a panel build
The Siemens SENTRON 3VA2063-5KP46-0AA0 is a 4-pole molded case circuit breaker rated for 63 A continuous current across the full ambient range from 40 °C to 70 °C — no derating needed up to that ceiling. The ETU850 electronic trip unit gives you adjustable long-time, short-time, instantaneous, and ground-fault protection curves, so it can be coordinated downstream of a larger feeder breaker without nuisance tripping. Breaking capacity is 187 kA at 240 V, 121 kA at 415/440 V, 75.6 kA at 500 V, and 3 kA at 690 V — the 690 V figure is low, so verify your fault current at that voltage before committing the BOM line.
Panel footprint and integration
The case measures 140 mm wide by 181 mm high by 86 mm deep — a standard 4-pole MCCB footprint that fits most DIN-rail or panel-mount enclosures without reworking the gland plate. Front-face protection is IP40, adequate for a clean indoor panel; no washdown rating, so keep it out of wet zones. Power loss is 5.4 W maximum at rated load — negligible for thermal budgeting in a crowded enclosure, but worth noting if you are stacking multiple breakers in a sealed box.