Schneider Electric B6.25 Thermal Overload Relay

The Square D (Schneider Electric) B6.25 Thermal Overload Relay delivers precise, current-based motor protection for three-phase AC motors in industrial control systems. This plug-in thermal heater unit, part of the Type B Thermal Unit series, senses heat via a calibrated melting alloy or bimetal element and trips the starter to disconnect the motor when overload or phase imbalance occurs, making it suitable for HVAC equipment, pumps, conveyors, and manufacturing machinery that require reliable protection. Key specifications include a current range of approximately 3.98–4.89 A, a Class 20 trip, manual or automatic reset depending on the starter, and plug-in mounting for compatibility with Square D starters and overload relay frames; it is used with 3-phase AC motor starters up to industrial ratings. Commonly installed in motor control centers and automation panels, the B6.25 provides protection to small to medium AC motors from overheating in continuous-duty industrial environments.