The surge arrestor consists of a semi-conductor valve element that opens at certain conditions At normal conditions of the system,the surge arrestor has infinitely high resisance between the protected conductors and earthing circuit.At voltage increase due to atmospheric nature or system failure,the valve element opens and leads the excessive voltage to the grounded circuit. After reversion of the normal voltage the valve element closes.The arrestor can endure high momentary overloading.

■ protection of heavy-loaded electrical circuits from overload
■ used to protect not only particular consumers/circuits,but also the whole panel
■ remarkable with high reliability of current characteristics
■ control:automatic switching off at exit failure and recovery after eliminating th danger

* Rated operating voltage Uc:the operating voltage of the surge arrester 275/440v;50Hz
* Surge voltage Up:the voltage created in surge arrester terminals at rated discharge current running:according to the tables
* Rated discharge current In-the rated value of discharge current with a sinusoid 8/20 us,which can be repeatedly led to the ground:according to the tables
* Full discharge current lmax-the peak value of the discharge current with a sinusoid 8/20 us,which the surge arrester can bear once:according to the table
* Constant operating current:up to 800 uA for 1p,2p ,3p,up to 600 uA for 1p+N,3p+N
* Indication for damaged surge arrester
* Offered in types:1p;1p+N;3p;3p+N

■ Fiexible or rigid conductors with corresponding section