Power Lines and Climbing

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Ive often wondered lets say you take 500' of copper wire, tie it off to an earth anchor and stake it into the ground under a transmission line. Walk back 200 or 300' paying out the wire and leaving the slack at the earth anchor; tie the wire to a throw weight and shoot it in an arch over the wires.

The weight would pull the line away from you and cross the phase, grounding it all out. Quite the sight I imagine!
 
I'd have to look again to be certain but I think it was transmission lines, very near two hydro dams. they aren't huge metal towers like in your pick though but I still think they are transmission lines. I know one of the guys who was on-site and they fell a big fir across the lines, it blew and had the auto-recloser go a couple of times and then stayed dead. Apparently the cua on-site bucked the tree off the lines while it was what he considered to be safe but before hydro came on the scene. He lost his ticket for it, he was the company owner too and had knocked power out to a huge rural area so he obviously in haste made a very poor and unwise decision, although he didn't have to pay for it with his life.
 
Ya, that's the designation up here for working around power. I'm not one, and have no desire to be. I'm cool around a coated service drop, the crackle of unprotected high voltage scares me though.
 
It's amazing how that's how I got into this back in '77. Trimming power lines with no training, whatsoever.

I should have killed myself many times over...
 
Here HO just calls the utility and tells them we are going to remove the tree. Utility sends crew out and takes tree down to under conductors. Drop stub & done.
 
It all depends on the local laws. In my state, the law requires that the power company be notified before any work is done within 10 feet of any distribution line. They will inspect and they alone will determine what is allowed to be done and by whom and when. The power company has NO sense of humor and will levy heavy fees for non-compliance. The local county laws govern any work on the power drop, requiring a licensed electrician. Certification, license, and insurance are also required by law.
 
Nick, it looks like your pic shows transmission wires on top and distribution wires below. Am I right? Alabama Power at times does this along streets in town, running 44KV on top, 7.2KV below. I'm not sure where the defining line between transmission/distribution lies, but we always defined distribution as the lines that distributed the power to homes, therefore the 44KV would be classed as transmission lines, though not near as large as the ones on towers.

*Edit: I see you're calling them primary and secondary distribution. I suppose it's six of one, half-dozen of the other....

I have climbed a few times in situations where I could have stretched out and touched the primary, always in yard situations where we weren't getting our normal 15' clearance. In yards, we were pretty limited to what the customer agreed to. In the case of the hard-headed ones who wouldn't grant much clearance, we assured them that if/when the tree(s) in question ever caused an outage, their power would not be restored until the problem was resolved. It usually worked, but not always.

Alabama Power is usually pretty good about dropping service lines, though they are often running late. I have dropped the service myself on four occasions that I can recall, and have had to put them back up twice. Once, the reconnect was done hot, as I had no way of killing the transformer. With the new radio transmitting meters, self-dropping is a thing of the past, as the computer sees immediately when the meter goes off-line. I looked at a job with Carl the other day where I may have to climb the pole and drop a service wire to a yard light. It'll depend on how accommodating the light company is.
 
Now that line clearance is not my job, no closer than necessary. I have been within 7'-8' feet a few times in the last couple of years, but it's not a normal thing. Alabama Power has pretty good clearances.

I took a sweet gum down for a guy several years ago where I had to work back overhang off a 3-phase. The light guys sat in their truck and watched after they dropped the service for us. Same crew was running late (45 minutes) the next morning, which led to me dropping it myself. (Two-day job). Overhang is not uncommon in yards.

To give a firm answer, I guess I'd say 5' would be my personal minimum distance on 7.2 KV primary, which is our common voltage.

As far as coated/uncoated, I don't put much trust in the coating on service drops, as I've seen too many times where squirrels have gnawed thorough it. Not only that, the ground/support cable is bare, and in the unlikely (but totally possible) scenario that something (limb falling, car clipping a pole, etc) caused a short, that bare wire will be a live wire with primary voltage for a split second. Back when I worked with Asplundh, there was a bucket crew trimming for the phone company. After trimming, the bucket operator was pulling hangers off the phone cable. He was leaning over it, with his belly on the cable. A car clipped a pole some distance away, and it fried him. Our GF brought pictures to show in the next safety meeting. It blew a hole in him, burned the boots to his feet, and "melted" his leather gloves to his hands. It was tough to look at.
 
Just remember that the "coating" isn't insulation - it's protection for the wire itself.

It's amazing how many people don't know that. I hear people all the time calling it insulation.

I was trimming some limbs back for a man a few months ago, with a couple of them being out over the coated drop. I saw several places where the squirrels had really gnawed on it, and then when I got a limb up off of the line (storm-broken hanger), I saw a place where one of the hot wires was literally hanging by a thread. I mean ONE strand of it was left intact. Between squirrels and the limb rubbing on it, it was barely hanging on. I could also see burned places where it had been grounding out, melting away at the coating. I asked him if his lights had been flickering. He said they had been for a few weeks, but he thought it was just the power. I told him to call the power company asap so they could get it fixed before it single-phased any of his stuff.
 
For clarification on this "coating " term .The tri plex going from the transformer to the house it is indeed insulation ,cross link polyethlene . A real real old service might be three individual lines on insulaters .Older stuff with insulation not to be trusted .

Some of the older promary lines might have ratty looking rubberized cotton ,this was termed "weather proof " not even used any more .This stuff you don't trust because you're dealing with voltages of up to 7200 volts to ground ,not the 120-240 on a residentual house service .

Not to sound like a smart alec but on this distrubution stuff but if you don't feel safe just don't do it .You seldom get a second chance .
 
More . Last summer Tom's brother in law who is also in the tree biz had one of his idiots run the lower boom of a nearly new Altec into the primarys spanning two phases .It burned up the main lift cylinder ,all the hoses and I think even the hydraulic pump .Did like 40 thousand in damages ,luckily covered by insurance .That doesn't pay for the loses of the truck being out of service for 6 weeks though during prime season .

So to cut to the chase you have to be carefull even in a bucket truck because stuff can happen .
 
For clarification on this "coating " term .The tri plex going from the transformer to the house it is indeed insulation ,cross link polyethlene . A real real old service might be three individual lines on insulaters .Older stuff with insulation not to be trusted .

Some of the older promary lines might have ratty looking rubberized cotton ,this was termed "weather proof " not even used any more .This stuff you don't trust because you're dealing with voltages of up to 7200 volts to ground ,not the 120-240 on a residentual house service .

Not to sound like a smart alec but on this distrubution stuff but if you don't feel safe just don't do it .You seldom get a second chance .

Far be it from me to argue with you, Al, you being my elder and all, but per Alabama Power, we were told to regard it as coating, even on tri-plex. I suppose they didn't want anyone getting overly confident and getting zapped. I'm not sure what they're take is on the cover as a definition, coating or insulation.

My service in underground, straight buried tri-plex. A friend of mine who works for Alabama Power said they have loads of trouble out of it as it gets older, shorting out underground. I've decided if I ever have trouble and have to have it dug up, I'll buy the conduit to run it from transformer pole to the house, just to prevent having to dig up the yard again. When they put mine in, the Asplundh crew that did it said their trencher was tied up somewhere else. They used a backhoe with a 24" bucket to put mine in. Talk about messing up the yard!
 
The "coating" on service drops is just a thicker coating than transmission lines. I presume they do that because they are closer to the ground. It's akin to insulation, but it isn't classified as that.
 
The problem with buried aluminum tri plex or quadra plex is the fact that aluminum is known as a sacrifing metal .If you get just one little tiny pin hole in it buried in the ground over time it will kind of disolve through galvanic action .

As far as terminoligy regarding conductors I can well imagine the utility companys just generalize so as not to make people over confident about working in the proximity of the lines .As such it might be a liability issue should they speak otherwise and somebody gets zapped .

I've never done any tree work around power lines but I've got hours and hours of air time working on the lines themselves .Ha ,the first time I "gloved " 4160 it must have taken me 20 minutes to get my nerve up .--memories ---:lol:
 
Now you get into distrubution lines every so often you might see 4 conductors on a "star" type spreader .It's not used that often nor generally for miles and miles ,usual short runs of maybe a few miles .Those are and have to be insulated for the voltage at hand because the conductors are only about 6 inchs apart .

They also make tri or quadra plex in high voltage which again is normally used for short spans off the main line .So again it's the terminoligy the power companies want to use .
 
Yup.. line drop. But if you are uninsured and don't get a line drop... best not..

If I was uninsured I wouldn't do any treework at all.

One bad mistake and you are screwed for life.

I can't even bid on State Forestry logging contracts without carrying insurance to 1 million $ liability.
 
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