Overview
The Allen-Bradley W58 is a eutectic alloy thermal overload heater element engineered for use in Bulletin 500 line motor starters and overload relays. Built to deliver Class 20 operation, this Type W heater element provides reliable, consistent protection across motor control applications. The W58 is the standard choice for general-purpose industrial motor protection.
Key Features
- Type W eutectic alloy construction — proven, thermally stable design for predictable trip behavior
- Class 20 operation — recommended for general industrial applications
- Bulletin 500 compatible — fits standard 500 Line overload relays and magnetic motor starters
- Multiple amperage ratings — supports Size 00–0 (17.2 A), Size 1 (17.6 A), and Size 2 (17.7 A) configurations
- Authentic Allen-Bradley OEM component — trusted quality and long field history
- New in Box condition — sealed, ready for immediate installation
Technical Specifications
- Part Number: W58
- Manufacturer: Allen-Bradley (Rockwell Automation)
- Type: Type W Heater Element
- Material: Eutectic Alloy
- Application: Bulletin 500 Line Starters and Overload Relays
- Trip Class: Class 20
- Current Rating (Size 00–0): 17.2 A full load
- Current Rating (Size 1): 17.6 A full load
- Current Rating (Size 2): 17.7 A full load
- Amperage Range: 16.2–20.5 A
- Weight: 0.10 lbs per unit
- Condition: New in Box
- Series: W Series
Typical Applications
The Allen-Bradley W58 is ideal for:
- General-purpose three-phase motor protection in industrial machinery
- Machine tool drives and production line equipment
- Pump and compressor motor control circuits
- HVAC and facility motor starters
- Replacement of failed or worn heater elements in existing 500 Line installations
Compatibility & Replacements
Compatible With
- Allen-Bradley Bulletin 500 Line magnetic motor starters
- Allen-Bradley Bulletin 500 overload relays
- Type W thermal overload relay circuits
- Motor control centers (MCCs) using 500 Line components
- Industrial motor protection systems rated for Class 20 trip operation
Replaces / Drop-In Replacement For
The W58 replaces failed or original W58 heater elements in Bulletin 500 overload relays. Verify exact heater number for your application’s amperage range before ordering. Consult the Allen-Bradley Bulletin 592 heater element selection chart for correct sizing.
Works With
- Bulletin 500 and Bulletin 509 overload relay platforms
- EtherNet/IP and Modbus industrial networks (when integrated into networked motor control systems)
- Any facility motor control architecture using Type W thermal protection elements
- Manual and automatic motor starters
