What this MCCB carries and where it fits
The Siemens SENTRON 3VA2063-5HN36-0AJ0 is a 3-pole molded case circuit breaker rated for 63 A continuous current, built around the ETU350 electronic trip unit. The interrupting capacity hits 187 kA at 240 V, 121 kA at 415 V and 440 V, and 79 kA at 500 V — numbers that tell you this breaker is sized for high-fault industrial distribution, not light commercial panels. At 690 V it still holds 3.4 kA, which covers most motor-circuit fault scenarios. The ETU350 is a basic electronic trip unit — no voltage trigger, no phase-failure detection, no communication module. It handles line protection (overload and short-circuit) with a fixed thermal-magnetic curve. The auxiliary contact version ships with 2 auxiliary switches plus 1 trip alarm switch (HP type), so you get status feedback and a separate alarm contact without adding a module. Temperature derating is modest: the breaker holds 63 A from 40 °C through 50 °C, then drops to 60.6 A at 55 °C, 58.3 A at 60 °C, 55.9 A at 65 °C, and 53.6 A at 70 °C. If your panel ambient runs above 50 °C, factor the derate into your load calculation.
Physical fit and panel integration
Dimensions are 105 mm wide, 181 mm tall, 86 mm deep. That 105 mm width is a standard 3-pole MCCB footprint — it drops into a SENTRON 3VA mounting base or direct panel cutout. The IP40 front protection means it's fine inside a closed enclosure; keep it out of washdown zones. Maximum power loss is 5.4 W — negligible for thermal budgeting in a typical distribution panel, but worth noting if you're packing multiple breakers in a small sealed box.
What the ratings mean for your BOM
The 63 A rating at 40–50 °C without derating is the headline number for feeder or main breaker duty. The 187 kA interrupting capacity at 240 V means this breaker can sit at the service entrance of a high-fault industrial panel without needing a current-limiting fuse upstream. At 415 V (common European distribution voltage), 121 kA still covers virtually all utility-transformer fault levels. The ETU350 trip unit is a basic electronic unit — it gives you adjustable thermal and magnetic settings but lacks the communications, ground-fault, or voltage-based protection of higher-tier ETU units. If your spec calls for Modbus monitoring or ground-fault alarm, this isn't the variant; you'd step up to a 3VA2 with ETU600 or ETU800.