Whenever the conductors are dead-ended of there is a change in the direction of the transmission line, the insulator. used are the
Right Answer is:
Strain type insulators are used for handling the mechanical stress at the angle position of the line i.e Dead end, intermediate anchor tower, corner, sharp curve.
- Large tension is experienced by the line when there is a sharp curve in the line or it crosses a river or at the dead end. In such cases, the pin insulators are not useful.
- For low voltage lines, shackle insulators can be used but for high voltage lines, strain insulators are used.
- It consists of discs in a vertical position as a suspension insulator but the insulator itself is placed in the horizontal position as shown in Fig.
- When the tension is too high, two, three, or four strings of insulators are used in parallel. This insulator has very good mechanical strength and also good insulating properties.
These insulators reduce the excessive tension on the line under such abnormal conditions. For low voltage lines below 11 kV shackle insulators are used but for higher voltages strain insulators are used.