What this 100 A MCCB is and where it fits
The Siemens 3VA2110-8KP42-0AA0 is a SENTRON molded case circuit breaker (MCCB) designed for line protection in distribution panels. It carries a continuous 100 A rating at 40 °C and holds that same 100 A all the way up to 70 °C — no derating needed for elevated ambient temperatures in a crowded enclosure. Four poles handle three-phase plus neutral, and the ETU850 electronic trip unit gives you adjustable overload and short-circuit protection curves. The interrupting capacity reaches 440 kA at 240 V, 330 kA at 415 V, and still 52.5 kA at 690 V — so it clears high-fault scenarios without cascading upstream. A communication function is built in, meaning it can talk to a higher-level control system for metering or remote trip indication — useful for a panel that needs to report breaker status back to a PLC or SCADA.
Panel fit and mounting
The breaker measures 140 mm wide, 181 mm tall, and 86 mm deep. That width is the standard 4-pole MCCB footprint for the SENTRON 3VA series — if you're swapping a 3VA2063 or 3VA2040 frame, the mounting holes and bus-bar centres should align without re-drilling the backplate. Front protection is IP40, so it's fine inside a closed panel but not for washdown areas. The undervoltage release is absent on this variant (no voltage-trip coil), and there's no ground-fault monitoring module — those are add-on options if your application needs them.
What the ETU850 trip unit gives you
The ETU850 is an electronic trip unit with adjustable overload (Ir) and short-circuit (Isd, Ii) settings, plus ground-fault alarm capability (though this breaker ships without the ground-fault monitoring module). It also supports communication — the 'Communication Function: Yes' flag means it's ready for a plug-in module or direct bus connection for remote monitoring.