What this MCCB is and what it does
The Siemens 3VA2110-6HN32-0KC0 is a SENTRON molded case circuit breaker (MCCB) rated for 100 A continuous current at 40 °C, with a rated insulation voltage of 800 V. It's a 3-pole line-protection device fitted with an ETU350 electronic trip unit — that's the microprocessor-based release that gives you adjustable long-time, short-time, and instantaneous protection curves, plus ground-fault alarm capability if you ever add the module. The interrupting ratings are serious: 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and still 5 kA at 690 V. That means it handles high-fault-current scenarios without cascading upstream — useful when you're feeding a panel off a large transformer or a utility service with stiff source impedance.
Built-in shunt trip and auxiliary contacts
This variant ships with a shunt trip (STL) release integrated — part number 3VA9688-0BL33 for the trip coil itself — and two auxiliary switches (HQ configuration) already wired in. The shunt trip lets you remotely trip the breaker from a PLC output, E-stop circuit, or fire-alarm panel. The two auxiliary switches give you status feedback (open/closed) without needing an add-on block. No undervoltage release, no communication module, no phase-failure detection on this build — it's a straightforward remote-trip + status package for a distribution panel or motor control center.
Thermal derating and panel fit
The breaker holds its full 100 A rating up to 50 °C ambient. Above that it derates linearly: 96.25 A at 55 °C, 92.5 A at 60 °C, 88.75 A at 65 °C, and 85 A at 70 °C — the maximum operating temperature. If your panel runs hot (say, a non-ventilated enclosure near a furnace line), you'll need to account for that derating in your load schedule. Physical dimensions are 181 mm high, 105 mm wide, 86 mm deep — standard SENTRON 3VA2 footprint, so it drops into the same mounting base and bus-bar system as other 3VA2 frame sizes. Power loss at rated current is 10 W max, which is modest for a 100 A MCCB; helps keep internal panel temperature down.