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linemanfrog
05-01-2007, 12:27 PM
I just read an article in "Incident Prevention" magazine about equal potential grounding. It stated that AEP has changed the method for creating an equal potential zone (EPZ). Apparently they did some testing and found that the pole band or cluster bar does not energize the heartwood of the pole where a workers gaffs penetrate, and thus does not actually protect the worker adequately. They recommeded to place a pole bond that extends down a min. of 10 ft from the neutral (full length pole bond prefered from top of pole to a driven ground rod) and connect it to the system neutral, staples should be a max of 18 inches apart and firmly driven into the pole. I spoke with a AEP rep and they verified the testing methods they used and solutions they came up with to correct the problem. They no longer require the use of the pole band or cluster but do require what is stated above. Other than the cluster mount the grounds should still be installed nueutral first then to each phase.

What are your company standards on this subject? I also heard GA Power has changed to this standard as well along with others. Any information we can share with each other will go a long way.

BigClive
05-01-2007, 07:28 PM
You get the feeling that each new safety feature introduces it's own new dangers.

Trampbag
05-01-2007, 08:17 PM
You got it Clive.

Traveling around really shows the glaring discrepancies between jurisdictions where safety is concerned. For the first decade I thought it was because every area had it’s own special circumstances but slowly it began to dawn on me that those special circumstances have more to do with employers, or groups of employers, and our own worker representatives (be them unions or associations) collectively trying to distance themselves from any liability what-so-ever.

If the powers to be were concerned about trying to truly make the job safer we would be seeing fewer serious accidents, many fatal. We are not seeing any statistical proof that that is so, but what we do see is some safety geek department of yet another utility putting a new spin on a flogged to death idea.

We have had numerous threads in this forum discussing the fine points of EPG methods, FR clothing, safety glasses and a myriad of other safety topics amongst ourselves and what has been accomplished? For me it is only proved the point I made in the first paragraph, “…employers, or groups of employers, and our own worker representatives (be them unions or associations) collectively trying to distance themselves from any liability what-so-ever.”

If anyone has noticed I have been spending most of my efforts on this site in the “Politics and BS” portion because I’m doing more good there, especially in BS.

Until we get our collective heads together as Linemen and quit arguing about whether 5 staples or 6 per 10 foot length is going to make a difference in the safety of our people this trade is doomed to continually suffer the jobs site meat grinder we call a trade.

It makes me hold my head and scream the sound that is never heard.

Bull Dog
05-01-2007, 08:29 PM
couldnt agree more and besides hes in the wrong thread!

PA BEN
05-01-2007, 09:29 PM
Until OSHA gives the OK to just a ground wire, it's a pole band. Plain and simple. The company can add a ground wire to the pole and use the pole band too. The EPG tests Iíve seen this is the best way to do it.:rolleyes:

linemanfrog
05-02-2007, 03:36 PM
Actually guys I would consider this to fall under safety meeting (the heading of this thread.) I do agree that this subject has been beaten to death over the past few years. Some companies do not fall under OSHA actually but use OSHA rules and regs as guidelines. I think as a industry wide thought that Equal Potential Grounding has been accepted. These other companies are not saying that this is wrong by any means. They performed tests that show the current method (pole band/cluster bar) can be ineffective. I personally want to protect myself as much as possible and if there is a better, more consistent way to provide a safer work area then I am all about it. From speaking with the guy they are actually attempting to make establishing a EP zone easier (no pole band/cluster bar) as well as making it more reliable and safer. As stated earlier I would like to know what other companies are doing and if they are considering changing to a different method why are they doing so? We can be proactive and help change happen in directions where we would like to see it go, or we can sit by and watch while people who have no idea about our job make the rules for us. I personally choose to be proactive and ensure that things are in my best interest where ever and when ever I can. So with that being said, does anyone have any helpful information on this subject?

500 KVA
05-10-2007, 08:59 PM
Cluster Bar is the only way. Staples????? Come on!

You try to get IEEE to go along with that one. When they stop laughing they'll say NOPE NOPE NOPE!

That pole ground and staples are covering a tiny portion of that poles surface. The surface is where the current is going to travel. Skin Effect. It's not just in wire. The cluster bar covers the entire outside of the pole. Not just on or two corners.

Your hooks are going to travel through the surface wood into the deeper wood. The depth of the wood your hooks will penetrate will not be any more moist than the surface.

I think a pole ground can help. Grounded cases on transformers too, but you must have that cluster bar circling the entire outside of the pole. No compromising! I won't let you on my pole.

linemanfrog
05-11-2007, 08:11 AM
I agree 500 the ground wire and staples does sound very if'y but according to the artcile's author it has been thourghly tested again and again on all different treated pole types. These results have been duplicated by more than one company as well.

If these results are accurate and have been duplicated by more than one company then you never know what IEEE or OSHA may or may not do.

Go online to Incident Prevention Magazine and look at the article. It does a lot better job explaining it than I have.

PA BEN
05-11-2007, 10:27 AM
EPZ. How many Companies out there require grounding of your trucks and those of you that do ground your trucks, how do you set up your work zone to protect ground personal? IE; bounding the truck together, ground mats, barricades and what do you uas for barricades, etc?:cool:

fastlane
05-11-2007, 01:04 PM
Out here its the band and cluster.Whats interesting is when you are EPZing on the underground with the mats and barricading whatever trucks are tied to it then just one transformer down the road has school kids sitting on it,I guess they dont need EPZ.

topgroove
05-11-2007, 01:40 PM
The apprentice in WA that was recently killed would be alive today if the crew had praticed EPG

500 KVA
05-11-2007, 04:58 PM
grounding trucks gives a false sense of security. If your relays are set correctly and you get a large enough rise in fault current, a grounded truck will trip the circuit.

At the end of a long line it will see it as load and just pump more current to the circuit. Your gonna be crispy either way if you are in contact with that vehicle when it becomes energized.

Current will take ALL paths back to its source. Not only the best. ALL Paths! That means if you are in contact with a grounded vehicle when it is contacting a source of energy, and you are at a different potential, current is going to flow through you! You are in series with the circuit.

That poor apprentice wouldn't have been helped by EPZ unless the building was bonded to the truck, and there was a bonding mat to stand on as well. Touching a truck and a metal building is going to put you at different potentials. Then you will get a voltage rise and subsequent current flow. subsequent death!

Ground your vehicles. Hopefully no-one is touching it and standing on the ground too. As I said, a false sense of security!

You need to Look up! Talk to the operator. Wear your rubber gloves, and wearing 20 KV rubber boots would be an added plus. An epz mat bonded to the vehicle with a rubber blanket to make the transition on and off of the mat.

Use your brain! Don't be another person talked about in the past tense.

topgroove
05-11-2007, 05:26 PM
grounding trucks gives a false sense of security. If your relays are set correctly and you get a large enough rise in fault current, a grounded truck will trip the circuit.

At the end of a long line it will see it as load and just pump more current to the circuit. Your gonna be crispy either way if you are in contact with that vehicle when it becomes energized.

Current will take ALL paths back to its source. Not only the best. ALL Paths! That means if you are in contact with a grounded vehicle when it is contacting a source of energy, and you are at a different potential, current is going to flow through you! You are in series with the circuit.

That poor apprentice wouldn't have been helped by EPZ unless the building was bonded to the truck, and there was a bonding mat to stand on as well. Touching a truck and a metal building is going to put you at different potentials. Then you will get a voltage rise and subsequent current flow. subsequent death!

Ground your vehicles. Hopefully no-one is touching it and standing on the ground too. As I said, a false sense of security!

You need to Look up! Talk to the operator. Wear your rubber gloves, and wearing 20 KV rubber boots would be an added plus. An epz mat bonded to the vehicle with a rubber blanket to make the transition on and off of the mat.

Use your brain! Don't be another person talked about in the past tense.
Yes of coarse weíre talking grounding mattes and bonding the building the pole the truck everything the worker may come in contact with. The other option would be to rubber up the primary and maintain your minimum approach distance. Using a dedicated spotter. And have everyone in rubber gloves and EH rated boots. Letís face it, many times when the digger rolls out in the morning you donít have a bucket with you. As I understand it this pole set was mid span with the primary 25 feet from the ground and in close proximity to the building. Iíll Say IT AGAIN EQUIPOTENTIAL GROUNDING WOULD HAVE SAVED THIS MANS LIFE.

500 KVA
05-11-2007, 06:40 PM
How do you bond to a customers building? That is nonsense!

Bond to a pole too? With what? # 6 copper. Where do you run that? To a ground rod that you will be walking around and flirting with the step potential, or maybe wrapping around yourself as well.

How many mats do we put out? 20? 40? Lets wrap the building too.

Placing a shield around the top of the pole would work.

Rubbering the phases is a great idea as well. Cover everything up. That'll work fine.

Another way to do it:

Think about what is going on and what could happen.
Take a step back and look around. Do a tailboard. Talk to each other.
Look up. Don't assume anything.
Don't touch the truck, and try to keep away from the truck if possible.
Don't get between anything. The pinch factor if nothing else.
Wear rubber gloves and Boots. WEAR IT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

You can EPZ all you want in this situation. But if he would have followed Apprentice Lineman 201 then we wouldn't be discussing this at the moment.

topgroove
05-11-2007, 08:00 PM
Iím sure you could figure out some way to ground the building and ten mats would be enough. Using pole guards and rubber would work. The fact is some hands arenít using anything and we read about the fatalities all the time. Something needs to change. Wearing rubber gloves and boots would be the easiest way but I guarantee In the middle of summer a lot of lineman will say screw itÖ Iím just spotting the pole and the boom will be no where near the primary. You can say stay away from the pole and truck but many times the guy on the ground is trying to maneuver the pole in position. We had PAR contractors on the property a few years ago and they had a double fatality and five injured simply unloading Transmission arms. I donít know what the answer is but somethingís got to change or these fatalities are going to keep on happening

PA BEN
05-11-2007, 11:07 PM
Very good questions 500. We have a new policy, it’s mandatory to ground our trucks now. We’ve asked all the questions but have not got any good answers. We had a guy from AB CHANCE give training. Each job site is different. Each work zone is different. #6 copper for a ground, the substation could see it as load, touch step potential is a big one, what if there is a metal fence on the job site, the list goes on. We were legal the way we worked before. Cover, cover and more cover. The feeder is on one shot on all jobs, we use pole grads for every pole set, wear rubber gloves for ever pole set, wing out phases, documented tail boards on all jobs, stay off the trucks, safety watch we did it all.

PA BEN
05-13-2007, 06:36 PM
EPZ. How many Companies out there REQUIRE grounding of your trucks and those of you that do ground your trucks, how do you set up your work zone to protect ground personal? IE; bounding the truck together, ground mats, barricades and what do you uas for barricades, etc?

THE KID
05-13-2007, 10:53 PM
I went to the Incident-Prevention in Nashville. Our company wants us to ground our trucks. The problem is we have a Unidelta system and we only tie the transformer down at the sub. There is no system neutral to hook to and they said in Nashville that a screw down ground is no good. So I dont have a clue what to ground my truck to. Our engineer does not agree with what we were told in Nashville about a screw down ground and that we will still use it to ground our trucks.

Trampbag
05-13-2007, 11:35 PM
Hi Kid and welcome,

If you read the third post in this thread, mine, you will discover how I am feeling about this horseshit. You nailed it.

I worked for a company once that demanded that the trucks be grounded, had to have a ground rod, and bounded. They supplied screw in ground rods 3 Ĺ feet long for this purpose. The GFs used to visit the sites at least twice a day and always checked to see that we were following company policy. Because we were working on roads and sidewalks, both concrete, and were close to the properties which had concrete or brick walls there was absolutely no place to screw in the grounds. Of course it was a delta system as well. Bet you can’t guess what we had to do?

You betcha. We tied the trucks together and connected to the ground rod and threw it under one of the trucks. It complied with company policy.

Fat lot of f**king good that would do tripping the circuit. Pity the ground men that had a 60’ X 8’ kill zone to deal with if things went south.

Things would have been much better if the screw in ground rod had been shoved up the Safety Engineers ass.

I can now imagine someone coming on here and saying that cover up would stop an unnecessary fatality under this situation or asking if the crew was wearing their rubber gloves.

Just a thought.

PK270
05-15-2007, 09:41 AM
I am going to try and find a video that our safety dept. showed us on screw grounds. The video shows fault current applied to the screwed in ground rod. That joker looked like the space shuttle taking off. We are required to use them if we cannot reach the pole bond but we stay clear of that the same we do the truck.

False sense of security we had for a long time. There are a lot of opinions but what is the real answer to keep us safe, and will the right answer today be the wrong one tommorrow.

You are your brothers keeper on a line crew, cover all the asses on site.

blackley
04-01-2008, 09:01 AM
Ok Guys here's some straight skinny - Think with me on this one.

1. What linemans gaffs penetrate the pole into the hardwood - none right.
2. AEP & GP have both conducted test GP's test was at 480 volts

Ask these people what the numbers were if you repair the pole ground (staple it down) AND USE THE POLE GROUNDING CLUSTER

Prudent workers will do both. AEP's testing shows that if we repair the pole ground we improve safety & if we use both then we get the best of both worlds - Think about it - It's your life not some engineer's who has never climbed a single pole.

Do'em both and go home safely tonight!

mainline
04-01-2008, 08:20 PM
Here in the 1950's we still bracket ground on distribution. We are only required to use a pole band and EPZ on transmission. Our engineers actually told us that the neutral bracket acted in the same way a pole band did. They didn't have an answer for me when I asked what happens when the neutral is above where you could possibly put your feet. Silence and a blank stare followed that question. We get that a lot from engineering. It is a good idea to ground digger trucks, as for grounding bucket trucks, that is a crappy idea why would you want ground the chassis of a truck with an insulated boom. If you need to do that and expose your ground crews to an additional hazards you have bigger problems with your work practices than can be discussed here. I knew one of the guys who was killed in the Transmission accident on Grids property. He was a good lineman who was killed by a shitty operator. Wear your rubber gloves, put on pole guards, keep you body clear of the pole, keep clear of the truck. Most importantly have a plan, and if you change it in the middle, make sure everyone knows what the change is. Work safe.

wtdoor67
04-01-2008, 10:54 PM
I am alive. I will live for a few years longer maybe. The rest of you SOB's are gonna die of "FEAR OF EPZ!!!!!!!!!!!! OH MY GOD!!!! Don't worry, Swamp Rat and I and that one other retired guy will manage to get the lights back on.

I think cigarettes,bad whiskey and wild women have been the death of more linemen than anything.

If we don't get this EPZ crap settled we're gonna have to shut down the grid. Wait. Call GW Bush. We can probably get a bunch of illegals to put everything back up.

Oh Hell. He's got that damn fence they're gonna have to contend with. Maybe they can get around the virtual part of it okay.

lewy
04-03-2008, 06:40 PM
We also use a pole band, as well as a hubbard clamp on the neutral for all tangent and small corner poles. As far as grounding trucks if we are working on a de-energized line we will ground an rbd if we are sticking the steel in the air, but not bucket trucks. If you do not ground your rbd and stick it in the air it would be at a different potential if something happened.