Page 320 - CITS - Electrician - Trade Practical

ELECTRICIAN - CITS

8 Get the draw pulley from the ground and secure it on the cross-arm. Interlace the rope through the pulley and
send the other end to the helper.
9 Ask the helper to properly tie the O.H. conductor to the rope and lift the conductor to the cross- arm position.
While lifting the conductor both the end conductors should be lifted at a time first, and then middle
conductors to avoid the fitting of the cross-arm.
While tying, the conductor to the rope the helper should leave atleast 1 metre length of conductor
free at the end from binding.

10 Twist the end portion of the conductor over the main line conductor. (Fig 2)
11 Bind the shackle insulators with the one fixed at the last cross - arm

Fig 1 Fig 2

Ground clearance of overhead conductor should not be less than 4.572 m for low and medium voltage.
12 Get down from the pole after checking the binding.

TASK 3: Install the pin type insulator in LT
1 Climb the next pole following the previous procedure
2 Lift the conductor and keep it on the pin insulator. Ask the other helper to lift and stretch the conductor with wire
stretcher.
3 Fix the pin insulator to the cross - arm of the existing pole.
If the span is less, there is no need to use a draw pulley, pulling with the help of a rope is sufficient.

4 Bind the pin insulators as per procedure.
The binding wire must be of the same metal as the line wire.
Binding should be mechanically strong.
Bind the free ends of the binding conductor over the line conductor tightly in the opposite direction.
(Fig 3)
Alternatively the conductor can be placed in the side groove for binding the conductor with the pin
insulator as in Fig 4.

Binding should be tight without any gap.
6 Complete the binding by giving about 15 turns on both sides.
7 Cut the extra binding wire and round off the raised ends.
8 Repeat the procedure for the other pin insulator by the side of the same cross arm.
Check the bindings before getting down. No tool and wire should be left on the cross-arm.

9 Test by a Megger of 500 Volt for insulation between conductors and insulation resistance between conductors
and earth.

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CITS : Power - Electrician & Wireman - Exercise 110