OVERHEAD TRANSMISSION LINES (OHTL) GROUNDING

 

OVERHEAD TRANSMISSION LINES (OHTL) GROUNDING

 


In general, a protection system must be provided for the transmission towers, as well as a safe environment for the personnel working on these towers. A grounding wire is used above the tower. And it has several names earth wire, shield wire, skywire, static wire. Its type can be steel or OPGW wire.

Lightning Protection

An important use of earth wire on transmission lines is lightning protection. It is a grounded wire or more placed above phase conductors for the purpose of intercepting direct strokes in order to protect the phase conductors from the direct strokes. to take these direct lightning strokes and shield the conductors. The lightning current is expected to follow a path along the shield wire, down the tower, and through the tower footing resistance to the ground. So Tower footing impedances should be obtained as low as is economically justified.

(OPGW) Ground Wire


OPGW ground wire is a dual functioning cable are grounding and telecommunications purposes. The conductor is constructed with a central optical fiber core surrounded by helically laid aluminum-clad wires, aluminum alloy wires, galvanized steel wires, or combinations thereof.

 

 

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