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gwolf001
01-06-2011, 02:57 PM
I work for a coop in central texas, durning a drought we experience alot of pole top fire on 3 phase pole with the primary voltage 14.400, and the pole are usually either a VC1-3 or any pole with (2) curved ridge pins on center phase. I'm wanting to see if anyone out there has experienced this same type of problem and what they have done to fix it. We have moved to a poly insulator but once they become dirty with dust i think they will track over also. would appreciate any feed back.

old lineman
01-06-2011, 05:38 PM
I work for a coop in central texas, durning a drought we experience alot of pole top fire on 3 phase pole with the primary voltage 14.400, and the pole are usually either a VC1-3 or any pole with (2) curved ridge pins on center phase. I'm wanting to see if anyone out there has experienced this same type of problem and what they have done to fix it. We have moved to a poly insulator but once they become dirty with dust i think they will track over also. would appreciate any feed back.

What's the additional cost of moving up to 25 or 35KV. insulators.
I'll bet a lot cheaper than replacing poles.
The Old Lineman

lewy
01-06-2011, 06:21 PM
We over insulate everything, I would also think it would help & depending on how bad the dust is, insulator washing as well.

gwolf001
01-11-2011, 09:25 AM
thanks for the reply
we have started building all new construction with the 35 kv poly instulator, i just don't know how long the poly will last in the texas sun. i don't want to start something that in 10 years will be worst then it is now.

topgroove
01-17-2011, 09:24 AM
http://www.valleycentral.com/news/story.aspx?id=567226 Officials are working to restore power to more than 4,200 homes and businesses in the three counties tonight.
Frank Espinoza with AEP Texas told Action 4 News the outages are being blamed on utility pole fires across the Rio Grande Valley.
Action 4 News confirmed that utility pole fires have been reported in the San Benito, Harlingen, Donna and Weslaco areas on Thursday evening.
Fire crews were called to put out the fires.
Espinoza said the fires were caused by drought and windy conditions, which caused dust to build up inside equipment on the poles.
The AEP Texas spokesman said it moisture in the air from the cold front had caused the dust to “cake” and cause a fire.
As of 8:45 p.m. Thursday, there were 3,227 customers with power in Hidalgo County.
Another 453 customers were without power in Cameron County while 554 customers were without power in Starr County.
Temperatures are expected to dip into the 40s tonight across the Rio Grande Valley.
Espinoza said AEP Texas crews are working to restore power as fast as possible.

Squizzy
01-19-2011, 08:25 AM
We get alot of Pole Top Fires here in West Oz. They do all sorts of stuff to reduce them, line washing towards the end of summer, also spraying insulators with silicon (prick of a job) also as The Old Lineman said over insulate all our 6.6,11 and 22kV lines are built with 33kV gear. Also ensure all hardware is tight often get fires on loose gang nail plates. The Old Guys also used to grease the pole bolts and believe it reduces the incidence of fires though I am not convinced on that one. We've been using the Polermeric stuff for years and haven't had any problems with UV destroying anything or noticed a spike in faults relating to the gear. Can only seem to recall seeing one poly that failed with a beauty of a burnt track over it. How is your stuff bonded over there? Bearing in mind all our new construction here uses steel arms for HV...

lewy
01-19-2011, 05:43 PM
We either dead end vertically on the pole or we only use steel arms which we do not ground. We over insulate all dead ends & we only use poly.

Highplains Drifter
01-19-2011, 06:47 PM
We get alot of Pole Top Fires here in West Oz. They do all sorts of stuff to reduce them, line washing towards the end of summer, also spraying insulators with silicon (prick of a job) also as The Old Lineman said over insulate all our 6.6,11 and 22kV lines are built with 33kV gear. Also ensure all hardware is tight often get fires on loose gang nail plates. The Old Guys also used to grease the pole bolts and believe it reduces the incidence of fires though I am not convinced on that one. We've been using the Polermeric stuff for years and haven't had any problems with UV destroying anything or noticed a spike in faults relating to the gear. Can only seem to recall seeing one poly that failed with a beauty of a burnt track over it. How is your stuff bonded over there? Bearing in mind all our new construction here uses steel arms for HV...


Squizzy, are you staying dry? I just talk to my buddy in Victoria and he is fine in his location. I'd figured you where working lots of time...but I see you had time to post. Let us know how the flooding has affected you...Drifter

Squizzy
01-19-2011, 07:02 PM
Yeah I am fine over here in Western Australia we had some fires 30 miles to the South of here which the South Metro Depot took care of. There are some receding floods in the Canarvon area about 600 miles to the North which we may be asked to go to. Queensland is 75% a disaster zone, New South Wales is flooding and about a third of Victoria is under water its not real good over there at the moment some of the Victorian towns are ones that were burnt out a couple of years ago in the Black Saturday fires that killed 173 people...

http://www.news.com.au/breaking-news/floodrelief

burnitup
01-21-2011, 12:21 AM
Bonding may help

Squizzy
01-25-2011, 09:53 AM
Yeah we used to do alot of bonding up until recently. Basically they would put gang nail plates between the King bolt and pole bolt of the HV arm and join it via a piece of 2.5 mm wire to a hose clamp around the bolts. Another gang nail plate above the Kingbolt of the LV arm joined to the kingbolt and to the neutral pin (seen a few pole fires start at this plate) Now we mainly use gang nail plates over the bolt holes till they change their minds again...

BillyMac
01-27-2011, 06:09 AM
Same here Squiz in QLD, gang nail plates on most Hv drilled bolt holes, king bolts,arm brace bolts,pin/insulator bolts ect. to help spread the leakage.
Narrow backs seem to think they there to stop the wood splitting.:rolleyes:

gwolf001
01-27-2011, 07:11 AM
Thanks all for your replys; we do not bond, we have it most of the time on 24.9 and it is on three phase poles and i have only seen it where it is on double support (curved ridge pins) on center phase, i have not seen it on a pole that has jusst one ridge pin, has anyone had an outside phase on cross arm catch on fire.
thanks

Squizzy
01-27-2011, 12:56 PM
Seen it a few times here. On the old wooden HV arms at various voltages the arm has a gang nail plate over the bolt hole at the end of it and the arm has shrunk as its dried out in the sun forcing the plate out and becoming loose the insulator then starts tracking and the end of the arm burns of. Had it one time and this old bloke accross the road was yelling abuse at us went over to what his problem was. The LV was a Tee off and the HV was intermediate the roadside phase burnt the end of the arm off and dropped over the LV, the HV then tracked down the neutral,down the nearest customers service to their earth stake which just happened to be this guys house right next to where he was standing watching the arm burn. He was in bare feet on concrete and copped the step potential and there was a dirty great splat mark on the patio roof where his coffee ended up lol:eek:

gwolf001
01-27-2011, 02:50 PM
thanks squizzy, I bet next time he will stay inside

lewy
01-27-2011, 05:13 PM
Yeah we used to do alot of bonding up until recently. Basically they would put gang nail plates between the King bolt and pole bolt of the HV arm and join it via a piece of 2.5 mm wire to a hose clamp around the bolts. Another gang nail plate above the Kingbolt of the LV arm joined to the kingbolt and to the neutral pin (seen a few pole fires start at this plate) Now we mainly use gang nail plates over the bolt holes till they change their minds again...

We use to have that on our 44. I remember taking that stuff off, I think it was at the pole ware the brace irons attached, but is has been a long time. We don't put any of that stuff up anymore.

Squizzy
01-28-2011, 10:07 PM
I did post a question some years ago on pole top fires and got differing answers. Basically if you bond everything together or use a steel crossarm you are putting a single conductor in a three phase magnetic field with each phase inducing a voltage in the single conductor is the resulting voltage Ac or DC? Remembering that any voltage in + cancells any - , would be an interesting experiment...

Squizzy
02-28-2011, 09:22 AM
Yeah they have changed our bonding now its a gang nail plate over any hole thats drilled in pole that has HV on it the plate obviously has a hole in the middle of it...

Meat1
04-09-2011, 05:23 PM
We use fiberglass arms on everything except deadends and we are getting some fiberglass buckarms to start using. We don't have the dust problems y'all have in Texas but maybe the fiberglass arms would help some. We also have fiberglass pole top pins. We use those alot on trouble if the top of the pole is blown out. I know they make different height pins also.

Squizzy
04-15-2011, 09:55 AM
Hey Meat, just curious about your fiberglass over there, we have trouble with it over here as the gel coat gets destroyed by the UV and then boxes and spreader bars become a furry mass of itchy sh!t when you have to disturb them couldn't imagine the gel coat failing on an arm and the crap job that would be to change out...

rob8210
04-15-2011, 08:15 PM
They used to have fiberglass 9" standoff brackets ( chicken wings). After a few years the sun would wreck the fiberglass and the bracket would become very brittle. They tend to break very easily, now.

Squizzy
04-17-2011, 08:55 AM
Rob, you are going to have to put some basic locality info on your profile thanks for the reply but no one knows even what country you are in...

lewy
04-17-2011, 05:08 PM
Rob, you are going to have to put some basic locality info on your profile thanks for the reply but no one knows even what country you are in...

I believe he is from Ontario Canada

Mc Klien
05-26-2011, 06:10 AM
We get alot of Pole Top Fires here in West Oz. They do all sorts of stuff to reduce them, line washing towards the end of summer, also spraying insulators with silicon (prick of a job) also as The Old Lineman said over insulate all our 6.6,11 and 22kV lines are built with 33kV gear. Also ensure all hardware is tight often get fires on loose gang nail plates. The Old Guys also used to grease the pole bolts and believe it reduces the incidence of fires though I am not convinced on that one. We've been using the Polermeric stuff for years and haven't had any problems with UV destroying anything or noticed a spike in faults relating to the gear. Can only seem to recall seeing one poly that failed with a beauty of a burnt track over it. How is your stuff bonded over there? Bearing in mind all our new construction here uses steel arms for HV...

yeappp . that was a brialliant idea but i know you are using wood pole and wood cross arm yet it has a factor of that easily burn while there is a leaking of your high voltage insulator maybe its pole top pin insulator or post insulator or a suspension insulator. the best thing to do is use a steel pole and steel cross arm then be sure that it is fully attached to the line ground which is the neutral or earth ground then be sure that your substation is in the right protection of all other over current of high voltage or in other words short circuit so that it is easly trip to the breaker or switching device.