500kV Refresher Training Part 2

Location : Ayer Tawar, Perak

Duration : 9th - 13th March 2009

The second session of our 500kV refresher training was held in Ayer Tawar, Perak. We pass by this place on the way to Lumut. The roads are now wider compared to few years back and drivers will feel safe using this road in any purposes. This second session of training was more challenging because we were dealing with energized transmission line.



Our meeting point was in Ayer Tawar substation where we would carry out the morning briefing and discussion regarding the work and tasks which has to be done for the day. The red and white painted structure is the transmission tower and those gigantic pillars are the busbars. The power will pass by the busbars, breakers, isolators and transformers before it could be distributed to the customers and industrial zones.





Part of the training was to replace upper string insulators at this tower. This tower carries the voltage of 500kV from Ayer Tawar to Junjung.It is a ST type tower and the angle of the tower is 45 degrees. Photos displayed below shows the process of and progress of replacing the insulators.



Handlines being placed and measurements are taken to ensure the appropriate location to assemble the boom. Boom is an assembly of 4 poles which will play the role of being like crane to hoist up the craddle and lower it down.

The final part of assemblying the boom is mounting the Gin Boom. The length of this Gin Boom is 19 feet and it plays the important role of controlling the craddle.



Boom assembly is completed and final checks being done to ensure the Boom is safe.







Lineman in position and waiting for the next task which is mounting the ladder. The 24 feet ladder will be mounted parrallel with the conductor in order to send hotmen to approach the 'live' conductor.




Ladder mounting in progress. There are two ways for hotmen to approach the conductor. One is by assemblying ladder and the other is by rope access where only insulated ropes used to swing hotmen towards the conductors. In this case, we decided to assemble the ladder.






The ladder will be hoisted up in level with the conductors by using 2/3 rope blocks and two control ropes will be tied both sides of the ladder to swing the ladder to left and right.







Aerial view of Boom from the tower.

Here is the hotmen in his position to start the task of replacing the insulators.



The arching horn has to be removed in order to mount the yoke which will be attached with strain poles to remove the insulator socket from it's clevis.



The dismantled arching horn will be lowered to the ground and will be fixed upon completion of the task.

Craddle been hoisted up and the process of changing insulators in progress.

The insulators has removed from the clevis and its ready to be replaced with the new insulators. The insulators prevent the current from flowing to the body of the tower and tests have to be done before replacing the insulators.