Square D thermal overload relay heater element unit B50

Description:

The Square D B50 Thermal Overload Relay Heater Element Unit is a calibrated thermal protection component used in motor starter systems to provide overload protection by converting electrical current into heat that operates the relay trip mechanism. It is designed to protect industrial motors from sustained overcurrent conditions by triggering a time-delayed trip based on thermal expansion.

Applications:

The Square D B50 heater element is used in Square D motor starters and thermal overload relay assemblies for industrial motor protection in conveyor systems, pumps, compressors, HVAC systems, and manufacturing equipment. It is commonly installed in motor control centers (MCCs), OEM panels, and industrial automation systems where accurate overload protection is required based on motor full-load current settings.

Technical Specifications:

• Manufacturer: Square D (Schneider Electric)
• Model: B50
• Product Type: Thermal Overload Relay Heater Element Unit
• Full Load Current Range: 27.1 – 36.1 A (depending on configuration and frame calibration)
• Trip Class: Class 20 thermal protection system
• Overload Type: Melting alloy / bimetal thermal sensing element
• Mounting Type: Plug-in heater element for overload relay base
• Function: Motor overload protection via time-delayed thermal trip mechanism
• Compatibility: Square D Type B / Type S overload relay frames
• Application Environment: Industrial motor control systems and MCC assemblies

Common Replacements:

• Square D B49 Thermal Heater Element
• Schneider Electric LRD Series Thermal Units
• Siemens 3RU11 Thermal Overload Heater Elements