Allen-Bradley 509-A0D Full-Voltage Motor Starter

The Allen-Bradley 509-A0D is a Bulletin 509 full-voltage, non-reversing motor starter designed for across-the-line starting and protection of three-phase AC motors in industrial settings. Built as a NEMA Size 0 open-type unit, it combines an electromagnetic contactor with an overload relay assembly (42185-800-01) and an auxiliary contact block (595-A) driven by a CB236 coil rated for 110V AC at 50 Hz or 120V AC at 60 Hz. Connection and mounting are panel-mount with an open-style enclosure for indoor industrial environments. It is commonly used with pumps, conveyors, fans, compressors, and mixers where reliable full-voltage motor starting and overload protection are required. Status: Legacy / Replacement component within the Allen-Bradley Bulletin 509 family.