Schneider Electric B45.0

This Class 20 Thermal Unit is designed to protect motors, controllers, and branch-circuit conductors from excessive heating caused by prolonged motor over-currents. The unit responds to overload conditions within 20 seconds or less, ensuring the safety of the motor and other branch circuit components. Its one-piece construction ensures durability and reliability. The motor current passes through a small heater winding within the thermal unit. Under overload conditions, the heat causes a special solder to melt, allowing a ratchet wheel to spin free and open the control circuit contacts and motor contacts.

This thermal unit is suitable for use in various applications where motor protection is required. It is compatible with Class 20 fuses or circuit breakers, providing additional protection against higher currents due to short circuits or grounds.