What this MCCB carries and where it fits
The Siemens 3VA2010-6HN32-0AJ0 is a 3-pole SENTRON molded case circuit breaker (MCCB) rated for 100 A continuous current at 40 °C ambient, with the ETU350 electronic trip unit set for line protection. It delivers 242 kA breaking capacity at 240 V AC, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 4 kA at 690 V — numbers that tell you it handles high fault-current headroom on the low-voltage side of a transformer or a generator feeder, but derates sharply above 500 V. The 86 mm depth and 105 mm width footprint fits standard MCCB panel cutouts; the IP40 front protection means it's suited for enclosed distribution boards, not open washdown zones.
Thermal derating and the ETU350
The 100 A rating holds flat from 40 °C to 50 °C, then steps down: 96.25 A at 55 °C, 92.5 A at 60 °C, 88.75 A at 65 °C, and 85 A at 70 °C. That matters in a crowded panel or a nacelle cabinet where internal ambient climbs — you size the load to the derated figure, not the nameplate. The ETU350 electronic trip unit gives adjustable thermal-magnetic or purely electronic protection curves; it ships without an undervoltage release or ground-fault module, so if you need those functions they're added via auxiliary releases. The 2 auxiliary switches plus 1 trip alarm switch (HP type) provide status feedback for a PLC or SCADA input.