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mainline
02-05-2007, 08:13 PM
I am looking for any information you guys can provide me on the safety procedures that you follow during conductor pulls, specifically, conductor pulls done in energized distribution space. What are your accepted grounding procedures ie. ground rod, system neutral, do you barricade your trailers, do you use an insulating mat to mount and dismount reel trailers and pullers. I am looking of any, and all procedures. Any information, especially in the grounding area would be appreciated.

boogerman
02-05-2007, 08:41 PM
These are some of our rules for stringing wire. All equipment is to be grounded to ONE drivin ground rod located away from the working area. A running ground is to be placed between the first structure and stringing equipment.A insulated platform is to be used if you have to adjust brakes on tensioning end. High voltage rubber shall be worn when operating equipment. Now this one is a little contraversial, wire is to be grounded after deadended before next wire is pulled.If wire is being pulled over energized wire it should be covered or de-energized and grounded. hope this helps.

mainline
02-05-2007, 09:24 PM
Thanks Boogerman. We have basically the same rules except for the insulated platform. What do you use for that. Is it shop made or purchased. A word of warning about the driven ground rod, they won't always open a recloser. We had a screw up pulling p-line during reconductoring which led to the rope being wrapped around the old wire. The lineworker following the bird couldn't see it till the wire got there. It energized the supposedly grounded trailer and truck attached to the trailer. It burned a perfectly good set of shoes on both. The ground rod was driven in about four feet till it hit ledge. If you can get to it go to the system neutral, its safer. Any info on the platform would be greatly appreciated.

tramp67
02-06-2007, 12:28 AM
If possible, a platform on the wire trailer and on the puller is best. The person operating each piece of equipment needs to stay on the equipment, thus it puts you in the same potential as the conductor being pulled, ie. bird on a wire. The grounding of the equipment and the rolling ground are for the purpose of operating the fault protection on the system, be it a recloser on one shot, a fuse, or a circuit breaker.

dwalla-walla
02-06-2007, 05:41 PM
We have gotten away from using a temporary ground rod. Our people tell us you create opportunities for alot of step potential this way. We ground all equiptment in the work area to the system neutral, use a traveling ground on the pulling end, and use a grounding block on both ends even though our bulletins say you only need one. Everyone has to wear overshoes and people operating the brake from the ground must wear primary gloves while standing on a tested blanket. After the pull, that blanket must be sent off to be cleaned and tested again. We always must use a recloser or station breaker. We are not allowed to use a fuse as protection.

boogerman
02-06-2007, 09:14 PM
The platform we have is made of fiberglass about 4 feet square with legs 6 to 8 inches tall. I would guess A B Chance would make something possibly Hastings also. We don't have much use for them now as our machines are the Shermin Rilley hyrdraulic machines real nice machines easy to run and control. We to must wear overshoes. I'll throw those questions out about the grounding location choices.

mainline
02-06-2007, 09:25 PM
Thanks guys, this is an excellent resource. I am in complete agreement about being on the trailer. I told my boss after our incident happened that we should junk any trailer that you can't stand on to operate. Our new sherman and reilly bullwheel trailers force you to, but some of the old ones don't have an adequate platform. It seems that everyone out there uses running grounds. Is there anyone out there using arbor grounds, thats what we use and I am wondering if they are as effective. Boogerman thanks for the info on the platform, and the comment about the overshoes I never even thought of that. Are the over shoes tested on the same schedule as your rubber goods?

TXsplitbolt
02-06-2007, 10:01 PM
Hey man we do the same the thing as yall but we also ground down our set up dollies (the first set to get wire) to the main line and only on one shot from sub

old lineman
02-06-2007, 11:05 PM
There's lots of interesting theories but none seem to afford the protection we were taught to achieve.
First of all everyone would be best off if they fully understand the Equipotential Zone (EPZ) concept.
I would like to look at it from the TENSIONING END and the PULLING END.
Before the tension machine is brought into place a ground mat should be laid down. We found that galvanized welded corn crib fencing was the choice. It can be purchased from TSC, Agway or any agriculture supplier. I think it comes in rolls 6'X60' and is reasonably priced.
Cut it into 3 pieces and lay it onto the ground then pull the tension machine onto it. Place the tongue right to the end of the grid area. That way you should have about 15' of grid behind the machine.
That area is used for splicing and gripping conductor while changing reels.
Normally we place 3 individual sections of fencing and slide one over the other until the desired width is aquired. Two- three feet of clearance on each side of the machine is good.
The 3 sections are bonded together. Once the tension machine is in place there should be a plastic fence erected around the perimeter. The only area to access the equipent is about 3' wide usually near the tongue.
If the truck is used for an anchor then it has to be disconnected from the tension machine and reconnected using a strain insulator. A short fiberglass rod is ideal or use an insulator, this is just to break up continuity. otherwise the truck needs to be barricaded, too much work.
The access area should have a piece of plywood laid down and an old blanket placed on top of it. The plywood if cut into three pieces and cable ties are used as hinges works really well. this allows it to be folded.
The blanket can be an old defective blanket. There is no need to use a good blanket and risk damage. Nothings energized here.
This is done to eliminate step potential for anyone walking into the area or out.
Tension machines have a grounding bar near the rear of the machine. This is where all the grounding clamps should be connected. One from each section of the grid, one from the travelling ground (running ground), and one goes to the system neutral. Never use hot line clamps
If you set your machine up like this you have created an Equipotential Zone. There is no need to wear rubber gloves to do any activity within this zone.
Boogerman said his company says that they have to. I can't understand why. This is exactly the same as the operator of a digger derrick standing on his platform (the bird on the wire). Perhaps his company also has these guys wear rubber gloves too. I think not.
As for an insulated platform, I can't see the purpose. Why would you try to separate yourself from the conductor. If for some reason it becomes energized the potential will be different than the worker. Super dangerous.
You should become energized at the same instant then the potential difference will be zero.
NO POTENTIAL DIFFERENCE, NO POSSIBILITY OF AN ELECTRICAL SHOCK.
That's the same as bare handing which can be done on every voltage on the planet.
One driven ground rod is a fart in the wind.
You should drive at least 4. They should measure 25 OHMS.
As you leave the reel end and head to the first structure the first traveller has to be gronded to the system neutral.
Along the run every fifth traveller should be grounded also. Use at least #3 copper. 1/O high flex is best.
On the pulling end the machine only needs to be grounded to the system neutral unless your pulling the new conductor with the existing conductor or the new conductor is going to be pulled right down to the puller.
Dwalla-walla puts the travelling ground on the pulling end.
I can't imagine this, it's only rope there unless a hardline is being used on transmission as the pulling medium. Then both ends are set up the same way
The travelling ground should be allowed to roll out on the conductor to about 10-12 feet otherwise it floats back and forth causing the conductor to gallop in the run.
Hope this helps.
The Old Lineman

tramp67
02-07-2007, 12:01 AM
Old Lineman's setup sounds great, but I have yet to work for a contractor that would go through the time and expense of as elaborate of a setup as that. Kudos to any employer that would allow such a setup! I like to use the anchor vehicle with the outriggers down, bucket digging into the ground if it's a backhoe, etc. A direct metal/metal connection, safety chains as well, and then you have another path to ground, granted it isn't a perfect ground setup, but neither are most other grounding methods we run across in the field. I'm sure most of you have seen the A.B. Chance video on grounding where their driven ground takes off like a rocket on a fault, at least I know the digger truck will stay put, even if it starts smoking! If you do isolate the anchor vehicle with a link or insulator, you need to remember to disconnect wiring and safety chains, and be aware of the difference in potential between the truck and the wire pulling equipment. The best bet, in my opinion, is to keep everything connected, with grounds, and barricade the equipment, make sure nobody touches the vehicle or equipment during stringing operations. The attached metal platform on the puller and tensioner is by far the safest for the operator of that equipment. The only times I have been fortunate enough to use grounding dollies on structures has been on transmission lines pulling next to a parallel transmission circuit. Rolling grounds, with a good connection, mechanically and electrically, and properly attached to the conductor with enough spring pressure, and bonded to the tensioner, is a better approach than the arbor ground. If you are using the arbor ground, you need to attach a ground from the conductor end on the reel to the arbor, and you are introducing another hazard to the operation. If the conductor does become energized, your ground will possibly whip out, and get caught on something, and then get ripped off or cause injury. The rolling ground is away from the person operating the tensioner, and is visible during the pulling operation. If it hangs up or gets somehow knocked off, stop the pull and reattach it while using rubber gloves. Attaching your equipment grounds to a system neutral would be great when possible, but many times you are set up too far away from a system neutral for this to be practical. As long as you stay on the platform, if something goes wrong, you can watch the world burn down around you and you will still be safe. There's lots of good information and ideas bouncing around from this discussion, and remember, there's always more than one way to be safe, and the setups are always different.

mainline
02-07-2007, 06:23 PM
Old lineman your setup ideas are excellent, though I doubt they are widely applied. My company requires us to use rubber gloves on pullers, reel trailers, and digger trucks all of which have to be grounded. I think this is because of a difference in potential between your hands and feet if you happened to be touching the brake controls when a trailer became accidentally energized. I like the barricading idea, we have already decided outside of company policy to do this on our own. We will also test driven grounds from now on. I don't know about the arbor ground being effective as a running ground, but in ten years I have never seen the tail pop out and whip around. We use a bolted connection on the wire tail then staple it to the reel. Thank you all you have provided me with a lot of food for thought. Just out of curiousity old lineman what is the setup time involved, and do you actually use this on roadside distribution, or mainly on transmission. Thanks again for the ideas.

old lineman
02-07-2007, 08:19 PM
Old lineman your setup ideas are excellent, though I doubt they are widely applied. My company requires us to use rubber gloves on pullers, reel trailers, and digger trucks all of which have to be grounded. I think this is because of a difference in potential between your hands and feet if you happened to be touching the brake controls when a trailer became accidentally energized. I like the barricading idea, we have already decided outside of company policy to do this on our own. We will also test driven grounds from now on. I don't know about the arbor ground being effective as a running ground, but in ten years I have never seen the tail pop out and whip around. We use a bolted connection on the wire tail then staple it to the reel. Thank you all you have provided me with a lot of food for thought. Just out of curiousity old lineman what is the setup time involved, and do you actually use this on roadside distribution, or mainly on transmission. Thanks again for the ideas.

This set up can be used for either/or. For someone not familiar it may seem over the top but look at it from a safety point of view and break it down.
We all know step potential is a potential killer ---the fence prevents random entry and the designated area is covered with a blanket.
Fence $100 and use it for years.
Blanket was scrap anyway.
Corn crib roll of fencing $80 and use it for years.
Time is money 1 hour set up and 1/2 hour break down.
Travelling ground you have to have anyway no extra cost.
Grounding the travellers, do it when they are positioned, extra time only minutes per location.
I still don't get the rubber glove thing. How would you think there would be a potential difference between hands and feet if everything is bonded together. Can't happen. That logic goes against all electrical theory.
You seem to be hanging on to the ground rods. Why?
An electrical connection to the system neutral eliminates the need for ground rods. If the system is Delta then go ahead with the ground rods.
If the neutral is crap back it up with ground rods.
In my little corner of the world safety is above everything else. It can't be compromised.
The Old Lineman

mainline
02-08-2007, 06:55 PM
old lineman, your right about safety being more important than money. You seem to be a pretty knowledgable so maybe you can fill me in a little on equipotential grounding. If the grounded trailer you are standing on becomes energized you are okay if you stay on the trailer. This means that in essence the trailer itself is your equipotential zone. As long as you barricade the trailer so that no one can approach it, and the operator remains on the trailer during pulling operations you have basically the same setup without the danger of the large energized mat. If this is incorrect please let me know. I think I gave you the wrong idea, we typically use a system neutral, and in the future I won't use anything but the system neutral.

old lineman
02-08-2007, 08:47 PM
old lineman, your right about safety being more important than money. You seem to be a pretty knowledgable so maybe you can fill me in a little on equipotential grounding. If the grounded trailer you are standing on becomes energized you are okay if you stay on the trailer. This means that in essence the trailer itself is your equipotential zone. As long as you barricade the trailer so that no one can approach it, and the operator remains on the trailer during pulling operations you have basically the same setup without the danger of the large energized mat. If this is incorrect please let me know. I think I gave you the wrong idea, we typically use a system neutral, and in the future I won't use anything but the system neutral.

I know that you and I could wrap this discussion up in a matter of minutes talking face to face, but it's a lot longer by posting. The reason I try to explain it in detail is because I know that thousands may become more informed.
My time is worth it if one person prevents an injury. Rusty does his part and I try to do mine as others do.
To your comments.
We all understand that a digger derrick has either an operators platform or a turret mounted seat. Either way the operator is on the machine and not bridging to the ground or another potential.
Thus he is within an equipotential zone (EPZ). We all also understand that should the truck become energized he would become energized along with the truck is but he will remain uninjured because everything he touches is the same potential.
Now if we talk about a tension machine the operator often stands beside the machine while it is paying out conductor. He does this because of inattention to the EPZ concept, becuse he's tired of the noise, the seat becomes uncomfortable or what ever.
If this worker has the radio hand set in his hand he is bridging between two potentials.
Something happens in the run and he's an injured or dead worker.
Let's see the comparison if the crew took the time to place a ground mat under everything and everything was bonded together then grounded to the system neutral or ample ground rods if there is no neutral as would be the case on a transmission stringing operation,and the same scenario occurred.
NOTHING because there is no potential difference.
Hope this helps.
The Old Lineman

boogerman
02-08-2007, 08:49 PM
Hey Mainline, our overshoes are never tested. they are good for 20,000 volts out of the box, and only visually checked for wear and punctures. The company hands them out as needed no questions asked. (at my shop). They were a pain at first but kinda caught on.

mainline
02-09-2007, 11:07 AM
Tramp 67, to answer your question my company has an almost exclusively wye distribution system. I can't think of a circuit that is delta. In the event that we ran into a delta system or were working on a transmission circuit I would use a tested driven ground. That would be pretty rare for us. Old lineman I understand your logic and I agree. If staying on the puller, and reel trailer accomplishes the same thing I think I would prefer to barricade them, and use them as the epz. I don't think you could run our sherman and reilly puller from the ground, and you would be foolish to do so. The puller is also equipped with a radio. Our reel trailers are now coming with bullwheels that force you to be on the trailer. I will bring this up in our discussions as we are going through a policy review because of our incident.

tramp67
02-09-2007, 10:57 PM
I don't know if you use a portable radio on the wire trailer, but since most of your work is distribution, you probably don't have any problems with getting out of range with a portable radio. If you need a more powerful radio, as you use in your trucks, the investment of a radio in a case, with room for a headset and a gel cell battery, and the use of a magnetic antenna, is something that you should be able to convince your company to have for the wire trailer so you don't have a headset cord going into your truck. That would basically using your body as a grounding jumper to your truck - yikes!! You are correct, staying on a platform on the tensioner or puller puts you in an equipotential zone, as does old lineman's mat and bonding method. It is easier to maintain a barricade around a piece of equipment than around a large mat, as the entire mat needs to be treated as something that can be energized at system voltage and can be lethal to anyone making contact with the mat anywhere along its perimeter.

dwalla-walla
02-10-2007, 08:05 AM
Sorry Tramp, I have never worked on a delta system before. Our's is a wye. Everywhere I have been on storms has been a wye system also. On storms I have worked for Entergy in La., Duke Power a few times, Dominion in Va., Mississippi Power, and Alabama Power. All wye where I was. Here in Georgia it's wye. Old Lineman, what we'll do with the traveling ground is to barely get tension on the wire, way before it to the first block on the pole, then put the traveling ground on. This limits the jumping and shock load to the rope and ground. Not saying our way is better. That is our cat skinning technique.

mainline
02-11-2007, 07:10 AM
tramp67, We use the hard mounted radio with a headset on the puller. It has its own box and antenna. I would never run one from the truck for the very reason you mentioned. I like the trailer instead of the mat because it is more compact. A lot of places we pull you wouldn't have room for a four arbor trailer a mat system, barricades, and all the rest of the crap though I agree with old lineman that the system they are using is very safe if uused properly.

lewy
02-26-2007, 07:02 PM
I agree with the old lineman any time we tension srting that is the only way to go . we apply the mats at both ends some companys only put the mats at the wire end, but we put them at both ends that way not relying on the insulated value of the rope. The only thing I think you left out is you have to set up the tension on both machines to make sure the wire does not get too much sag in it .