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-   -   Roofer fatally shocked from overhead wires. (http://www.diychatroom.com/f18/roofer-fatally-shocked-overhead-wires-184737/)

sirsparksalot 08-04-2013 11:37 AM

Roofer fatally shocked from overhead wires.
 
This got me to wondering how, since the POCO's overhead wires are insulated (the ungrounded conductors, anyway), how this happens. It wasn't reported that any of the wires broke loose.

??

At any rate, this should serve as more warning for us electrical DIYers.

http://www.14news.com/story/23038392...-roofing-house

joed 08-04-2013 11:53 AM

Not all wires are insulated, especially older services. Many times there are bare section near where the connections where made. A metal ladder could have scraped off the insulation.

Oso954 08-04-2013 12:00 PM

Your title is assuming a "fatal shock". It is just as likely that the two story fall was the fatal event.

mpoulton 08-04-2013 02:43 PM

The splices at the weatherhead are often very poorly insulated, or not at all. Also, the article doesn't say the shock was from the service entrance cables. Could have been contact with nearby primary, as often happens to painters and siding installers. Could have been random abandoned wires up there (old AC unit?). I had a commercial jobsite where someone had removed two rooftop units and left the cut-off flex whips laying on the flat roof. They were 480V 3ph, and hot! Looked like it must have made quite a show in the rain.

kbsparky 08-04-2013 05:18 PM

Most medium and high-voltage distribution wires are NOT insulated. That is why they are mounted on insulators.

dmxtothemax 08-05-2013 06:57 PM

Assuming that low voltage conductors are insulated (I don't believe so),
What condition was the insulation ?
If it's been out in the weather for a long time,
Then it's condition could well be poor.
Also banging into it with sharp edged roofing iron,
Would easily penetrate that insulation.

In Australia very little of the overhead conductors are insulated,
I would assume USA is simulair.

PoleCat 08-05-2013 07:05 PM

The original drops in my neighborhood are bare wire. Most have been updated but there are still quite a few of the OEM. My next door neighbor had them running through his oak tree and when it rained the light show was spectacular! I finally talked him into getting them replaced, freebie courtesy of Dayton Power & Light;

mj12 08-05-2013 09:29 PM

so what exactly happens to painters and siders? I ask, what should not by touched near a house, what are common electrical precautions to take?

MTN REMODEL LLC 08-05-2013 09:39 PM

Quote:

Originally Posted by dmxtothemax (Post 1225541)
Assuming that low voltage conductors are insulated (I don't believe so),
What condition was the insulation ?
If it's been out in the weather for a long time,
Then it's condition could well be poor.
Also banging into it with sharp edged roofing iron,
Would easily penetrate that insulation.

In Australia very little of the overhead conductors are insulated,
I would assume USA is simulair.

Quote:

Originally Posted by PoleCat (Post 1225548)
The original drops in my neighborhood are bare wire. Most have been updated but there are still quite a few of the OEM. My next door neighbor had them running through his oak tree and when it rained the light show was spectacular! I finally talked him into getting them replaced, freebie courtesy of Dayton Power & Light;


DMX and Pole.... I have no experience with these conditions/situations....

Just curiosity.... how are the wires/servoices held apart from each other.... just a safe distance as strung, or with some kind of insulator for standoff????

Tia

mpoulton 08-05-2013 10:14 PM

Quote:

Originally Posted by mj12 (Post 1225648)
so what exactly happens to painters and siders? I ask, what should not by touched near a house, what are common electrical precautions to take?

Painters and siders often use long poles or handle long pieces of material. Where primary (high voltage) lines run near a house, they can accidentally contact a line with something. The result is always horrible. This is not as much of a risk in most newly built areas, but old buildings were often constructed with less clearance from power lines. The wires from the utility to the house are only 120V, so not as much of a hazard as the 7200V primary but still responsible for many injuries and deaths. A mild shock on a rooftop can cause a fatal fall. Anyone who is not electrically trained should stay well clear of all overhead wires. They are not reliably insulated, as a rule.

dmxtothemax 08-05-2013 10:16 PM

Quote:

Originally Posted by MTN REMODEL LLC (Post 1225651)
DMX and Pole.... I have no experience with these conditions/situations....

Just curiosity.... how are the wires/servoices held apart from each other.... just a safe distance as strung, or with some kind of insulator for standoff????

Tia

Safe distance apart !

Stand off's usually only used in windy or cyclone prone area's

Kyle_in_rure 08-05-2013 10:19 PM

Quote:

Originally Posted by MTN REMODEL LLC

DMX and Pole.... I have no experience with these conditions/situations....

Just curiosity.... how are the wires/servoices held apart from each other.... just a safe distance as strung, or with some kind of insulator for standoff????

Tia

In my area, older bare wire services are simply held further apart. It's like the two 120 legs plus the neutral you see feeding street lights, except further apart.

sirsparksalot 08-05-2013 11:01 PM

Quote:

Originally Posted by Oso954 (Post 1224987)
Your title is assuming a "fatal shock". It is just as likely that the two story fall was the fatal event.

Yes, you are correct; that doesn't, however, answer the full scope of my post.

sirsparksalot 08-05-2013 11:09 PM

I was thinking of the lines from the pole to the weatherhead. I've cut and restored several of these for service upgrades, using split-bolt connectors. And they are always insulated, except, of course, for the neutral.

Depending on our POCO to come out and restore anything is usually an exercise in futility.

ddawg16 08-05-2013 11:35 PM

The report is lacking some information, but as one poster said, it sounds like maybe the fall is what killed him.

That's assuming he caught the low voltage wires going to the house.

I would be really surprised if he was able to reach the medium voltage wires.

When I built my garage...I wanted to push it back to the property line....one of the topics came that came up...because my garage is 2-story...they wanted to make sure no one could touch the medium voltage lines from the roof of the garage...I believe the min distance is 8'.


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