what is the line components of transmission line

Here present the line components of overhead transmission line.

The line components of overhead transmission line the electric power is transmitted through a bare conductor generally made up of A.C.S.R.(aluminum conductor steel reinforced). This conductor is kept above certain height from the ground to maintain clearance between them to avoid the arcing grounds.

This Fig. Shown the components of the overhead transmission system.


  • Conductors: conductors are used to carry electric power from sending end to receiving end. Conductors used for transmission and distribution purpose are made up of copper, aluminum or A.C.S.R.


  • line supports: line supports are used to maintain the clearance between conductors and ground line supports are of either wooden, steel, RCC construction depending on the application.
  • Insulators: insulator provides very high resistance path between line conductor and earth/support. Also it provides support to line conductor. According to system voltage, pin type, suspension type, shackel type or strain type insulator are used.
  • Cross arm: it provides horizontal clearance between the two conductors. It is a mounting accessory of line support which provides platform for insulators.
  • Stay sets: stay set provides support to the end pole or coener pole. These are braces of iron wire wound spirally.
  • Ground wire: it is run on the top of the pole/tower throughout the length of line. Ground wire protect the transmission line from lightening strokes.
  • Lightening arrestors:  L.A. are used to protect the line components from high voltage discharge. One terminal of L.A. is connected to the line and other terminal is earthed. 
  • Fuses and isolating switches: these are required to isolate different sections of overhead line.
  • Miscellaneous items: such as phase plates, danger plates, anticlimbing wires,(guard wires), 'V' guards etc.






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