What the ratings mean for fit
The Siemens SENTRON 3VA2010-8HN42-0AA0 is a 4-pole molded case circuit breaker (MCCB) rated for 100 A continuous current across the full ambient temperature range from 40 °C to 70 °C — no derating required up to that ceiling. That 100 A figure holds steady at every 5 °C increment through 70 °C, so the thermal curve is flat within the operating envelope. The breaking capacity is 440 kA at 240 V, stepping down to 330 kA at 415 V and 440 V, 220 kA at 500 V, and 53 kA at 690 V. For a panel designer, that means this breaker can sit at the service entrance on a high-fault installation and still coordinate downstream without cascading upstream. The ETU350 electronic trip unit gives adjustable N-conductor protection (OFF, 50%, 100%) and an adjustable response time (tr) from 0.5 s to 17 s. That adjustability matters when you're coordinating selectivity with downstream breakers — you can dial in the time band to match the load's inrush without nuisance tripping. The 20,000-cycle mechanical endurance is per the latching count; this is a line-protection breaker, not a switching device for frequent load cycling.
Panel integration and mounting
The 3VA2010-8HN42-0AA0 measures 140 mm wide, 181 mm high, and 86 mm deep. That 86 mm depth is the dimension that determines gland-plate clearance and whether the breaker fits a shallow enclosure without a protruding deadfront. The front face carries IP40 protection — suitable for a clean indoor panel, not for washdown environments. No communication module is integrated; this is a standalone line-protection breaker without fieldbus or measurement functions.