A type of arrester barrier consists of two sphere electrode S1 and S2 which are connected, respectively, to the line and the arrester. The auxiliary needle is placed between the mid of two sphere and S1 and S2 What type of lightning attester is it?
1
Expulsion Type Lightning Arrester
2
Impulse Protective Gap Arrester
3
Horn Gap Arrester
4
Auto valve Arrester