• Thermal overload relays protect motors from overheating caused by excess current. • They trip only after unsafe current persists, not for harmless temporary overloads. The blog explains how it works, compares manual and automatic reset options, and highlights benefits like easy installation, phase-loss protection, and. TL;DR: Thermal overload relays are essential motor protection devices that prevent electrical equipment from overheating by monitoring current flow and automatically disconnecting power when excessive loads persist. In combination with contactors, they provide reliable protection against overloads and phase failures for motors.