HV transmission lines during rain

[mbrooke]

I was working at a new NG turbine power plant and one day it was rainy and foggy. The conductors for the 315kV lines were arcing past the insulators and the arc was going to the steel on the towers.

We were told that was a normal condition for that type of weather.

Id say those insulators hadn't been cleaned ever. Either that they were undersized. In theory you can get away with a lot of corona communications aside, but its not a good idea.


Beginning of this video you can hear the noisy insulators, which I admit is on the high side but not that abnormal. Same thing in the sub but the transformers drown it out at certain points:

https://www.youtube.com/watch?v=T0m0tnCLSHY

 

[K8MHZ]

Id say those insulators hadn't been cleaned ever. Either that they were undersized. In theory you can get away with a lot of corona communications aside, but its not a good idea.


Beginning of this video you can hear the noisy insulators, which I admit is on the high side but not that abnormal. Same thing in the sub but the transformers drown it out at certain points:

https://www.youtube.com/watch?v=T0m0tnCLSHY

Your are probably right. The insulators were only about a year old and part of the first phase of construction. They were probably very dirty due to the dust from the traffic in the field next to them. We all had to drive through a field and park behind the plant to work there, and when we were building the second phase of it, there were hundreds of people there.

 

[Sahib]

Corona is mild but if there were arcing i.e flash over across the insulators, the insulators would have damaged.

 

[hurk27]

Corona is mild but if there were arcing i.e flash over across the insulators, the insulators would have damaged.

With glass insulators you would be surprised at how much arcing they can stand, glass is made of silicone or sand and does not have any carbon to cause carbon tracks like the old wood insulators or even plastic, but if the arc last long enough it can cause the insulator to crack or shatter, arcs can be as hot as the surface of the sun but it takes time to transfer the heat into the glass which is why most times the insulator survives the arc.

Some of the new ceramic insulators are even more robust against arcs as they don't crack or shatter from the heat.

Guess I shouldn't say new as they have been around for some time and are the most common type in use today.

 

[GoldDigger]

Glass is made mostly of silicon dioxide, called silica. Silicones, OTOH, are compounds of silicon, carbon, oxygen and hydrogen.
The distinction is important
The area around Santa Clara and San Jose where the modern electronics and computer industry began is Silicon Valley. The strip club area along Broadway in San Francisco where Carol Doda became famous was Silicone Valley.

Tapatalk!