OVERHEAD GROUND WIRES
The most effective method of providing protection to transmission lines against direct lightning strokes is by use of overhead ground wires as shown in Fig 6. For simplicity, one ground wire and one line conductor are shown. The ground wires are placed above the line conductors at such positions that practically all lightning strokes are intercepted by them (i.e. ground wires). The ground wires are grounded at each tower or pole through a low resistance as possible. Due to their proper location, the ground wires will take up all the lightning strokes instead of allowing them to line conductors. The degree of protection provided by the ground wires depends upon the footing resistance of the tower.
Written by John on March 20th, 2009 with
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