What it is and where it fits
The Siemens 3VA1110-1AA36-0CA0 is a SENTRON switch disconnector in a molded-case circuit breaker (MCCB) design — 3-pole, rated 100 A, with no overload or short-circuit protection built in. It's a pure disconnect, sized for the 3VA1 frame (160 A frame), and it carries an undervoltage release (UVR) coil rated 120-127 V AC 50/60 Hz. Rated insulation voltage is 800 V, operating voltage 690 V AC or 500 V DC, so it handles standard 400/480 V panels and some DC bus work. The 100 A rating holds flat from 40 °C all the way to 70 °C — no derating curve to chase in a warm enclosure. Termination is front-terminal clamp connection, which means you can land cables without pulling the unit off the DIN rail. Mechanical life is rated 15,000 operating cycles — typical for a panel disconnect that sees daily use but not continuous switching.
What the undervoltage release means on site
The UVR (undervoltage release) on this 3VA1110-1AA36-0CA0 is a factory-fitted auxiliary release that trips the disconnect when the control voltage drops below about 70% of its 120-127 V AC rating. That's a standard safety feature for conveyors, pumps, or any load that must not auto-restart after a power dip — the UVR holds the contacts open until the control circuit is deliberately re-energized. It does NOT have a leading contact (= No), so the UVR doesn't sequence ahead of the main contacts. If you need that for delayed dropout on a motor circuit, you'd spec a different variant or add an external time-delay relay. The UVR coil is 120-127 V AC only — don't feed it 240 V control power without a step-down transformer.
Lifecycle and sourcing reality
That said, the 3VA1 frame is a mature platform. If you're filling a BOM line or replacing a failed unit in a live panel, this order code is the direct drop-in. It's sourced through independent distribution — availability and current pricing confirmed at quote time against an RFQ.
Panel fit and physical constraints
Dimensions are 70 mm deep, 76.2 mm wide, 130 mm tall — standard 3-pole MCCB footprint for the 160 A frame. It mounts on DIN rail (implied by the MCCB design) and the front-terminal connection keeps wiring accessible without removing adjacent units. IP40 on the front means it's protected against tools and small wires but not washdown — keep it inside a sealed enclosure if there's moisture.