Overview
The Square D B36 overload relay thermal unit is a plug-in thermal heater element engineered for use with Square D motor starters and overload relays. This thermal unit uses melting alloy sensing method with plug-in mounting and is classified as Motor Tripping Class 20 with standard trip type. Ideal for maintenance technicians and system integrators, this lot of 20 units provides essential replacement components for maintaining motor control systems in industrial facilities, HVAC equipment, and process machinery.
Key Features
- Full load amperage range of 17.5 to 24.6 amps
- Melting alloy sensing method with standard trip type
- Plug-in mounting for quick installation
- Rated for 600V maximum operating voltage
- Lot of 20 units for bulk replacement and inventory stocking
- Authentic Square D B Series thermal unit
Technical Specifications
- Amperage Range: 17.5 to 24.6 A full load
- Motor Tripping Class: Class 20
- Voltage Rating: 600V AC maximum
- Sensing Method: Melting alloy
- Trip Type: Standard trip
- Mounting Style: Plug-in
- Operating Temperature: 40°C ambient
- Manufacturer: Square D (Schneider Electric)
Typical Applications
Designed for use with thermal overload relays, magnetic motor starters and motor controls, the B36 thermal unit is commonly applied in:
- Three-phase induction motor protection
- HVAC compressor motor control circuits
- Industrial pump and fan motor protection
- Machine tool motor circuits
- Commercial and industrial automation systems
Compatibility & Replacements
Compatible With
- Square D magnetic motor starters (Size 0 and 1)
- Square D B Series thermal overload relays
- Square D Class 8536 and similar motor control products
- NEC Article 430 Part C compliant applications
Replaces / Drop-In Replacement For
The B36 thermal unit directly replaces other B36 heater elements in Square D motor starter assemblies. Verify the original thermal unit amperage rating matches the 17.5–24.6A range before ordering.
Works With
- Square D motor starter enclosures and control panels
- Magnetic contactor-based motor control circuits
- Standard industrial electrical distribution systems
- Applications requiring NEMA compliance for motor protection












