Protects against low and excess power (under-voltage/Over-voltage) that will certainly damage any refrigeration appliance’s compressor.

Protects your appliance by disconnecting the power when it goes below/over unacceptable level.
Additionally, there is a delay when power returns to normal. This will ensure that the appliance is not switched on-off repeatedly during fluctuations nor is it subjected to a massive surge normally experienced when power returns after power cuts.