Insulators
To prevent a flow of electricity from the conductors through to the ground, the cable, bus bars, circuit-breakers and transmission lines are all supported or suspended on insulators. Insulators are made of non-conducting material such as porcelain or glass. The higher the voltage being carried by the conductor the longer the column of insulator needed to support it. To prevent columns of trickling rainwater forming a conducting path down the sides of the insulator special shapes are used. For high voltage conductors a number of skirt-shaped sections are used. The higher the voltage the greater the number of skirts.
Transmission lines from power stations are collected in switchyards at major centres such as Sheffield and Palmerston. From these places they carry electricity to major substations that service different areas where electricity is used.
Insulators, 110 000 volt
transmission line
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