What this SENTRON switch disconnector is for
The Siemens SENTRON 3VA1110-1AA42-0DC0 is a 4-pole switch disconnector in an MCCB-style frame, rated for 100 A continuous current. It provides visible isolation for a circuit — no overload or short-circuit protection built in, so it's used ahead of separate protective devices where you need a lockable disconnect point. The built-in undervoltage release (UVR) rated 208-230 V AC 50/60 Hz automatically opens the switch when control voltage drops, which is common on safety circuits or emergency-stop chains where loss of control power should kill the load. Two HQ auxiliary switches give status feedback to a PLC or panel lamp.
Ratings that decide the fit
Rated continuous current Iu is 100 A — that's the maximum load it can carry continuously without overheating. The rated insulation voltage Ui is 800 V, and max operational voltage hits 690 V AC 50/60 Hz or 600 V DC. On the short-time withstand side, it holds 2 kA for 1 second and the same for 0.5 seconds — that tells you the fault current it can survive closed before a downstream breaker clears it. Power loss maxes at 38 W, which matters for thermal management inside a sealed enclosure. Front protection is IP40 — fine for a dry panel, not for washdown.
Panel fit and connections
Dimensions: 130 mm high, 101.6 mm wide, 70 mm deep. Main circuit connects via busbar connection at the front terminals — no rear or plug-in option here. The UVR and two HQ auxiliary switches are factory-installed; no field wiring of separate release modules. Operating temperature range is -25 °C to +70 °C, storage from -40 °C to +80 °C. The MCCB-style frame means it mounts on a panel plate or DIN rail adapter, not a standard 35 mm rail directly — check the mounting kit included (nut keeper kit per the description).