Overview
The Allen-Bradley W53 thermal overload relay heater element is a precision-engineered eutectic alloy component designed for industrial motor protection and control circuits. Part of Rockwell Automation’s legacy 500 Line family, the W53 delivers Class 20 thermal trip protection for a wide range of motor applications in NEMA-style starters and overload relay assemblies. Its proven eutectic design ensures consistent tripping curves across ambient temperature variations, making it a trusted choice for maintenance technicians and system integrators managing legacy and new installations.
Key Features
- Type W eutectic alloy construction for stable thermal response and precise tripping curves
- Class 20 trip classification suitable for general-purpose motor applications
- Compatible with Bulletin 500 line starters and NEMA-style 592 overload relay assemblies
- Manual reset mechanism for safe shutdown and controlled restart
- Covers multiple frame sizes and full-load amp ratings (11.1 A to 11.5 A across sizes 00–2)
- Authentic Allen-Bradley / Rockwell Automation product with long-term field reliability
Technical Specifications
- Manufacturer: Allen-Bradley / Rockwell Automation
- Part Number: W53
- Type: Thermal Overload Heater Element
- Construction: Eutectic Alloy
- Trip Class: Class 20
- Heater Type: Type W (legacy 500 Line series)
- Reset Type: Manual
- Applicable Frame Sizes: 00, 0, 1, 2
- Full Load Amps – Size 00/0: 11.1 A
- Full Load Amps – Size 1: 11.4 A
- Full Load Amps – Size 2: 11.5 A
- Condition: New in Box
- Standards Compliance: NEMA
Typical Applications
The W53 heater element is commonly used in:
- Bulletin 500 and Bulletin 509 three-phase AC motor starters
- NEMA IEC overload relay assemblies (e.g., 592 series)
- General-purpose induction motor protection circuits
- Industrial machinery control panels and motor branch circuits
- Retrofit and replacement installations in legacy automation systems
Compatibility & Replacements
Compatible With
- Allen-Bradley / Rockwell Bulletin 500 line motor starters
- NEMA-style overload relay assemblies (e.g., 592 series)
- Bulletin 509 three-phase motor starters
- Manual and magnetic contactor assemblies using Type W heaters
- Industrial control systems using legacy 500 Line protection schemes
Replaces / Drop-In Replacement For
The W53 is the direct replacement heater element for Class 20 protection in 500 Line overload relay assemblies. Verify the specific frame size and full-load amp rating against your nameplate requirements before installation.
Works With
- Bulletin 500 and 509 motor starter assemblies
- NEMA overload relay accessories and trip mechanisms
- Three-phase AC power systems (standard industrial 460V, 380V, 220V)
- Manual and automatic restart control circuits
- Rockwell Automation legacy motor protection documentation and selection tables
