Switch disconnector, 100 A, with undervoltage release
The Siemens 3VA1110-1AA36-0DA0 is a SENTRON switch disconnector in MCCB design — 3-pole, rated 100 A continuous across the full ambient range from 40 °C to 70 °C, so no derating curve to manage in a warm enclosure. It carries 690 V AC and 500 V DC operating voltage, with an insulation voltage rated at 800 V. The built-in undervoltage release (UVR) is wound for 208-230 V AC 50/60 Hz, which drops the load if control power is lost — useful for safety isolation or emergency-stop circuits where a maintained disconnect is required.
The 100 A rating is flat to 70 °C — no thermal headroom lost as ambient climbs, which is unusual for a molded-case device and simplifies panel coordination. The UVR (undervoltage release) is the only auxiliary release fitted; there are no auxiliary switches or communication functions on this variant. Front terminal connections with clamp terminals accept standard copper cable.
Front terminal access means wiring from the front without reaching behind the panel. The UVR coil draws its control voltage from a separate 208-230 V AC circuit; verify the control transformer taps before commissioning.