The ABB OTM125F4C21D380C is a 4‑pole motorized automatic transfer switch (ATS) / change‑over switch designed to automatically transfer electrical loads between two independent AC power sources — such as the utility mains and a standby generator — in three‑phase low‑voltage power distribution systems. This switch features a motorized operator for automatic source switching triggered by internal logic (C21D controller class) and also supports manual override via a handle or external control. A mechanical interlock ensures that the two sources remain electrically isolated and prevents them from being connected at the same time, enhancing safety and protecting equipment.
