Transient Voltage surge voltage suppressors are voltage clamping devices which limit the transient voltage to a safe value. Transient Voltage Surge suppressors are made of shunting elements which are sensitive to high voltage. They are made in the form of gas discharge tubes, silicon avalanche diodes or metal oxide varistors.
Transient Voltage Surge Suppressors differ from Surge suppressors in that they are specifically designed for transients and not for normal surges. Besides, Transient Voltage Surge Suppressors can only be used in the LV side whereas surge suppressors can be used at all voltage levels.
Since, Transient Voltage Surge Suppressors are connected between the line and the ground, the system should have an efficient earthing system for the Transient Voltage Protection to be effective.