Allen-Bradley 509-B0D Size 1 27A Motor Starter

Allen-Bradley 509-B0D is a NEMA size 1, three‑pole motor starter (Series B) built to switch and control small three‑phase motors. It uses a 120 V control coil and is designed for 50/60 Hz power delivery, with a line‑voltage range of 115–575 VAC and a maximum motor voltage rating of 600 VAC. The unit has a continuous current rating of 27 A and is specified for motor loads in the 2–10 HP range depending on the supply voltage, with typical ratings of about 7.5 HP at 200–230 VAC and 10 HP at 415–575 VAC. This makes it well suited for on/off control of modest three‑phase motors in industrial equipment. Applications include drives for conveyors, pumps, and fans where a compact, reliable contactor is used to interface a 120 V control circuit with higher‑voltage motor circuits. The 509‑B0D is compatible with standard three‑pole wiring configurations and is manufactured by Allen‑Bradley, a brand under Rockwell Automation, providing a proven option for integrating into control panels and motor starter assemblies.