Hydraulic LRD Thermal Overload Relay, Boksburg

We supply and fit in all types of hydraulic LRD thermal overload relays for all trucks. The device shown is a thermal overload relay, which is designed to protect electrical motors from damage caused by overcurrents. While the query mentions a "hydraulic" LRD relay, the device is a thermal relay that operates based on heat generated by current flow, not hydraulic pressure.
On a truck, a thermal overload relay would be used to protect an electric motor from overheating and failure. It works by monitoring the current drawn by the motor. If the motor draws excessive current for a prolonged period, which can happen if the motor is stalled or overloaded, the relay's internal bimetallic strips heat up and bend, tripping a contact that cuts off power to the motor. This prevents the motor windings from burning out.
This type of relay can be used to protect various motors in a vehicle, such as those for:
Power windows
Wipers
Cooling fans
Pumps (e.g., for hydraulic systems, although the relay itself is not hydraulic)