What it is and what it does
The Siemens 3VA1110-4EF36-0DH0 is a SENTRON molded case circuit breaker (MCCB) designed for line protection in distribution panels. It carries a continuous current rating of 100 A at 40 °C, holds that rating flat through 50 °C, then derates to 98 A at 55 °C, 96 A at 60 °C, 94 A at 65 °C, and 91 A at 70 °C — so in a warm enclosure you lose about 9 % of capacity at the top of the operating range. Three-pole construction, with a rated insulation voltage of 800 V. Maximum power loss is 27.5 W — that's the heat you need to vent from the panel, not just a datasheet number.
Breaking capacity — what it means for fault duty
This MCCB interrupts 121 kA at 240 V, 75.6 kA at 415 V, 52.5 kA at 440 V, and 11.9 kA at both 500 V and 690 V. Those are the symmetrical short-circuit ratings that tell you whether this breaker clears a fault without welding its contacts or rupturing the case. At 690 V the 11.9 kA figure is the limiting factor — if your upstream transformer can deliver more, step up to a higher-rated frame.
Built-in undervoltage release
Factory-fitted with an undervoltage release (UVR) — part of the auxiliary release design. That means the breaker trips automatically when supply voltage drops below a set threshold, which is standard for motor feeder circuits where you don't want automatic restart after a dip. The auxiliary switch complement is two auxiliary switches plus one trip alarm switch HQ.
Panel fit and dimensions
Mounts on a DIN rail or direct-panel mount. Width is 76.2 mm (3 in), depth 70 mm (2.76 in), height 130 mm (5.12 in) — that's a standard 3-pole MCCB footprint. The 70 mm depth means it clears most shallow enclosures, but check the gland-plate clearance if you're back-paneling with a dead-front cover.