What it is and what it does
The SENTRON 3VA1112-1AA42-0KD0 is a 4-pole switch disconnector on the IEC frame 160 platform, rated 125 A. It provides visible isolation for a circuit — no overload or short-circuit protection built in, so it's a pure disconnect for maintenance lockout or load-break duty where upstream protection is already in place. The unit ships with a shunt trip (left-mounted, 208–277 V AC 50/60 Hz or 220–250 V DC) and a 3-auxiliary-switch changeover block fitted. The nut-keeper kit is included for the mounting screws — a detail that saves time on the panel build.
Panel integration notes
Mounts on a DIN rail in the standard enclosure. The 4-pole footprint and the shunt trip add width — verify rail space before committing the back panel layout. The auxiliary switch block is pre-wired to a terminal interface; no loose flying leads to manage.