The ABB AL9‑40‑00 is a 4‑pole AC magnetic contactor from ABB’s A‑Line (AL) contactor family, designed for switching and controlling three‑phase power circuits and motors. It is a compact, non‑reversing contactor used in industrial control panels, motor starters, lighting contactor applications, and general power distribution switching. The device uses a laminated magnetic coil and movable contact assembly to reliably make and break power circuits up to medium voltage levels.