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#3953 09/01/01 04:10 PM
Joined: Dec 2000
Posts: 4,294
Member
The other day I saw an Edison employee high up in one of the steel towers washing off insulators with a hose. There's a 1" Galvanized water line that runs up the tower. He had his pump truck down below, and a short length of hose and nozzle up above.
These transmission lines are up in the hundreds of thousands of volts, and he's perched right on the grounded tower!

What enables him to do this without becoming an instant french fry?

#3954 09/01/01 05:02 PM
Joined: Aug 2001
Posts: 151
D
Member
Well, ya know how a bird sets on a wire, or a squirrel runs along one....

Honestly, I don't know how. Maybe the line was dead?

Uh, why would they wash insulators? Ain't that what rain is for?

#3955 09/01/01 06:17 PM
Joined: Jan 2001
Posts: 1,044
Tom Offline
Member
Rain does not do an adequate job of cleaning the insulator.

What enables him to do this is the fact that water does not conduct electricity.

Tom


Few things are harder to put up with than the annoyance of a good example.
#3956 09/01/01 06:58 PM
Joined: Dec 2000
Posts: 4,294
Member
Is this water deionized or something?

#3957 09/01/01 08:01 PM
Joined: Oct 2000
Posts: 5,392
S
Member
distilled water is a very poor conductor, but knowing that i would still not be inspired to play hose tag with 100KV

they just don't make enough Coors...!

[Linked Image]

#3958 09/02/01 12:06 AM
Joined: Aug 2001
Posts: 151
D
Member
Rain does a pretty good job around here in the Midwest... of course it rains fairly often, and in more than sprinkles.

I've never seen insulators being washed, and I've seen utilities mowing treetops with helicopters, and maintaining the lines from a hydraulic boom suspended from that helicopter. What a ride.

#3959 09/02/01 10:17 AM
Joined: Aug 2001
Posts: 142
B
Member
Quote
Originally posted by sparky:
distilled water is a very poor conductor, but knowing that i would still not be inspired to play hose tag with 100KV

they just don't make enough Coors...!

[Linked Image]

Chemistry 101, water that does not have a ph of 7 will conduct electricity, a ph of 1 to 6.99 is acidic and 7.1-14 is basic, either side of the neutral point a 7.0 will conduct electricity. If distilled water is not at a ph of 7.0 it too will conduct electricity.

#3960 09/02/01 05:46 PM
Joined: Jan 2001
Posts: 1,044
Tom Offline
Member
Distilled de-ionized water is what is used. On the West coast, fog moving in from the ocean will deposit a layer of salt on the insulators. When I lived on the central coast, at night I could usually see, and hear, some arcing on the insulators. PG&E usually used a large tanker truck & washed them from ground level, no PPE involved.

I'm not going to dig out my old chemistry books, but for water to be acidic or basic, wouldn't it have to have something in it that isn't water?

[This message has been edited by Tom (edited 09-02-2001).]


Few things are harder to put up with than the annoyance of a good example.
#3961 09/02/01 07:04 PM
Joined: Aug 2001
Posts: 142
B
Member
Quote
Originally posted by Tom:
Distilled de-ionized water is what is used. On the West coast, fog moving in from the ocean will deposit a layer of salt on the insulators. When I lived on the central coast, at night I could usually see, and hear, some arcing on the insulators. PG&E usually used a large tanker truck & washed them from ground level, no PPE involved.


I'm not going to dig out my old chemistry books, but for water to be acidic or basic, wouldn't it have to have something in it that isn't water?

[This message has been edited by Tom (edited 09-02-2001).]

You should dig out the old chemistry book to make a blanket statement that water doesnt conduct elecctricity, is rediculous. AS I said if the ph is at 7 it will not conduct, going to either side of the neutral point causes it to conduct. Yes of course it would have to have something else in it, minerals appear quite naturally in nature aka hard water, or sulphur smelling water which we have a lot here in Ohio, acidic, tap water will conduct too. Even distilled water left out will become contaminated. As far as washing insulators I have never heard of it but we dont have rolling blackouts either.

#3962 09/02/01 07:40 PM
Joined: Aug 2001
Posts: 599
N
Member
Quote
Originally posted by bordew:
As far as washing insulators I have never heard of it
It's done all the time here in the west.
Quote
Originally posted by bordew:
but we dont have rolling blackouts either.

Don't speak too soon. Deregulation is a cancer and it is spreading.

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