509-DOD - Allen Bradley Magnetic Starter

509-DOD - Allen Bradley Magnetic Starter

If you’re running motors in a real-world environment—not a lab—you already know how important consistency is. The Allen-Bradley 509-DOD is one of those starters that earns its keep by doing its job reliably, without constant attention.

This is a NEMA Size 3 direct-on-line (DOL) motor starter designed for straightforward motor control and protection. It handles up to 90 amps of continuous current and supports motors up to 7.5 horsepower, making it a solid choice for common industrial loads like pumps, compressors, and conveyors.

What makes this unit especially practical is its temperature-compensated overload protection. Instead of reacting too quickly—or too late—it adjusts based on actual conditions. That means better protection for your motor and fewer unnecessary shutdowns.

You’re also getting factory-installed auxiliary contacts, which saves time during install, along with external reset capability and support for emergency stop setups. Internally, the use of silver alloy contacts and treated metal components helps extend the life of the unit, even in tougher environments.

Key Features and Benefits

• Built for consistent motor starting and protection in everyday industrial use
• 90A continuous current rating handles demanding equipment
• Temperature-compensated overload relay helps prevent overheating without nuisance trips
• Comes with 2 normally open auxiliary contacts already installed
• Supports emergency stop applications and external reset
• Silver alloy contacts improve durability and electrical performance
• Rated for up to 5 million mechanical operations
• Simple screw terminal connections make installation straightforward

Technical Specifications

• Catalog Number: 509-DOD
• Type: Direct Online (DOL) Motor Starter
• NEMA Size: Size 3
• Continuous Current: 90 A
• Service Limit Current: 104 A
• Max HP: 7.5 HP @ 115V (1-phase)
• Control Voltage: 110V (50 Hz) / 120V (60 Hz)
• Auxiliary Contacts: 2 NO (expandable up to 8)
• Overload Relay: Eutectic alloy, temperature compensated
• Trip Class: Class 30
• Max Inrush Current: 947 A
• Connection Type: Screw terminals
• Wire Size: 8…1 AWG
• Mechanical Life: 5,000,000 operations
• Operating Temperature: Up to 65°C
• Mounting: Vertical, rail mounting optional
• Enclosure: Open type
• Contact Material: Silver alloy

Material Compliance and Certifications

• Meets IEC 60947-4-3 (Class 2 coordination) standards
• Built to NEMA Size 3 specifications
• Corrosion-resistant treated metal components
• Suitable for installations up to 10,000 ft (with derating)

Where It Works Best

• This starter fits right into applications where reliability matters more than bells and whistles:
• Manufacturing equipment
• HVAC systems
• Pump and fluid handling setups
• Conveyor systems
• Compressors and general motor-driven machinery