100 A MCCB with ETU350 — what the ratings mean for your panel
The Siemens 3VA2010-7HN42-0AA0 is a 4-pole SENTRON molded case circuit breaker rated for 100 A continuous current across the full ambient range from 40 °C to 70 °C — no derating curve to chase (–). That flat thermal performance is unusual for an MCCB this size; most breakers start backing off above 40 °C. It carries an ETU350 electronic trip unit, which gives you adjustable long-time, short-time, instantaneous, and ground-fault protection curves. The insulation voltage is rated 800 V, so it's comfortable on 480/600 V distribution without voltage derating concerns. The interrupting ratings are what drive the selection: 330 kA at 240 V, 242 kA at 415/440 V, 187 kA at 500 V, and 3 kA at 690 V (–). That 330 kA at 240 V is a high-fault-capacity figure — it handles utility-transformer secondary faults without needing a current-limiting fuse upstream. At 690 V the 3 kA rating tells you this is not a 690 V main breaker; it's a line/feeder breaker on lower-voltage distribution.
Footprint and panel fit
Dimensions are 86 mm deep, 140 mm wide, 181 mm tall (–). That 140 mm width for a 4-pole 100 A MCCB is compact — it fits a standard 600 mm wide enclosure with room for side-feed lugs or a shunt trip accessory. IP40 on the front means it's protected against tools and solid objects larger than 1 mm; fine for a clean indoor panel, but keep it out of washdown zones.