Schneider Electric B50 Thermal Overload Relay

The Schneider Electric Square D B50 Thermal Overload Relay Heater Element Unit delivers calibrated thermal protection for industrial motors by converting live current into heat to actuate the relay's time-delayed trip. Designed for Square D Type B and Type S overload relay frames, this plug-in heater element supports a full-load current range of 27.1–36.1 A (configuration and frame calibration dependent) and uses a melting alloy/bimetal sensing element with Class 20 trip protection. Commonly installed in motor control centers (MCCs), OEM panels, and industrial automation systems, it protects conveyors, pumps, compressors, HVAC systems, and other manufacturing equipment. Common replacements include Square D B49, Schneider Electric LRD Series thermal units, and Siemens 3RU11 thermal overload heater elements.