For higher voltages, a string of suspension insulators is used. String efficiency of suspension insulatorsis an important part in using process by person thinking about.

Why the String efficiency of suspension insulators is important?
◆ Insulators for overhead lines are considered to be of basic importance to the transmission system, through their ability to insulate the power lines as well as their function in carrying the weight of the line conductor. Composite suspension insulator can be used on overhead transmission lines.
◆ For higher voltages, a string of suspension insulators is used. The number of insulator units used depends on the voltages of the lines. The voltage is not equally shared between the units in a suspension insulator string.
◆ The capacitances between each cap/pin junction and the tower and between the cap and pin of each unit determine the voltage distribution. Porcelain suspension insulators are normally used in insulator strings.
◆ Calculation of the voltage distribution can be made by different methods. In this article, these calculation methods and a formulation for each method are studied theoretically through computer programs in case of clean-dry condition.
◆ String efficiency comparison for each method is presented, and studying the equalizing voltage drops across insulators is also covered. 

Relative Articles:
◆Suspension insulators,IEC U70C suspension insulators
◆Cap and pin type suspension insulators
◆Voltage distribution in suspension insulators
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◆Electrical disc suspension insulators
◆Ceramic Porcelain suspension insulators