The ABB B6‑40‑00 is a compact 4‑pole miniature contactor from ABB’s B‑series, designed for control and switching of single‑phase or three‑phase AC loads where space is limited. As a mini‑contactor, it combines a small footprint with sufficient capability for many low to medium‑power applications such as lighting circuits, heating, small motors, pumps, HVAC systems, or other general-purpose loads. Its 4 main poles (4 NO contacts) support switching of all phases (and neutral if needed), making it versatile for different wiring schemes. B6‑40‑00 features a relatively low‑consumption coil, silent (hum‑free) operation, and offers a variety of connection types (screw terminals, flat pins, solder pins) depending on variant — making it suitable for panel or DIN‑rail mounting, installation in compact control cabinets, or retrofit in existing systems.