Questions on different practices?

[Ryan Zito]

I'm a journeyman from First Energy( Ohio Edison ), out of Akron, Ohio. I'm on the executive board of our Union, and also on the Union Safety Committee. We recently had a blow out with the company over what we felt was a safety violation based on our past work practices. A apprentice lineman B was given a direct order by a foreman to make repairs on underground primary cable that was faulted. The cable was grounded, but there was another energized cable in the ditch with the faulted cable. They were approximetely 3-6 inches from one another. The other cable also had gone bad in the past because there was a splice in the enegized cable where the faulted cable was excevated. Our work practices have always been not to get in a ditch with enegized underground conductors. We have recieved a standoff of all such activity after a lengthy safety invesigation with upper company officials. Being a safety committee member, I can foresee this problem comming up again. I have seached many of the OSHA information and other company information, but info is vauge at best. I would appreciate any info either way, of what your people or companies do.

Thanks,
Ryan Zito ryanzito74@yahoo.com

[Lineman North Florida]

Seeing as how one primary cable had already faulted and had a previous splice in it, there is a very good chance that that is the reason for the second burnout, hence possibly doing damage to the other cable again, I would'nt care what the company said it's a matter of working safe and if they wanted it fixed I would have de-energized the other cable, tested for dead and grounded and then spliced it.There is no reason that I can see for anyone to want you to do it any other way, I can only guess that by killing the other cable it was going to take some lights out, but so be it, it's not like it's going to take a long outage to do a URD splice anyway. Sounds like you know the right thing to do,stick to your guns and keep those apprentice's safe.

[Edge]

I'm a journeyman from First Energy( Ohio Edison ), out of Akron, Ohio. I'm on the executive board of our Union, and also on the Union Safety Committee. We recently had a blow out with the company over what we felt was a safety violation based on our past work practices. A apprentice lineman B was given a direct order by a foreman to make repairs on underground primary cable that was faulted. The cable was grounded, but there was another energized cable in the ditch with the faulted cable. They were approximetely 3-6 inches from one another. The other cable also had gone bad in the past because there was a splice in the enegized cable where the faulted cable was excevated. Our work practices have always been not to get in a ditch with enegized underground conductors. We have recieved a standoff of all such activity after a lengthy safety invesigation with upper company officials. Being a safety committee member, I can foresee this problem comming up again. I have seached many of the OSHA information and other company information, but info is vauge at best. I would appreciate any info either way, of what your people or companies do.

Thanks,
Ryan Zito ryanzito74@yahoo.com

What your saying is straight up man... Local 71? they started that ratty **** sub tecs and operators as foreman on linecrews... just cuz the cable is insulated and jacketed does not mean that it aint still HOT... yeah concentrec neautral is a great thing but WTF man theres a splicle right there in the ****ed ditch where they are working??? thats madness... does anyone up there know about step potential?... how do they know that the old "repaired" cable is good after they just dug it up? oh wait lemme guess you're walking in die boots... yeah thats what your gonna do if you touch anything with any other part of you body WHILE WORKING IN A FUGGING DITCH!!!

I'm sorry man but the people that are oppsed to killing the other circuit are fuggin idiots and should be out there some time ... let them put THEIR life on the line... see how they react...

fight it brother fight it... you're doing the right thing and that "foreman" .... send his ass down the GD road....

Edge

[loosescrews]

the municipal i'm at puts everything in conduit and all cables are in there own pipe. we put in four for three phase .on the others always the spare. nothin around here is direct buried to many problems around here. as far as workin on any of it we kill it all. we have a few left where all three in the same pipe but now that's a thing we don't do.to many problems being all together.

[US & CA Tramp]

OSHA regulations on maintaining the Minimum Approach Distance (MAD) have been tested in court for this type of action, and have been upheld in favor of the worker to maintain the MAD from the cable.

If the foreman or company can not guarantee the cable is affectively grounded then tell the apprentice or lineman to cut the cable outside of the ditch with hot cutters and install blankets on the hot phase with sticks from outside the ditch. The company or Foreman won't like the time involved but the lineman will not be refusing to do the job. It is the lineman’s right to use all the protective cover he or she sees fit.

[US & CA Tramp]

Like said above, you already know it's wrong-don't do it. I've seen the aftermath of a blown slice in an open trench and no amount of cover will do a **** bit of good if it was to fault with a man working next to it.


I did not see your previous post, but I guess the point I was trying to make was too subtle.

When dealing with management there is sometimes a fine line between refusing work for safety concerns, and insubordination. It is not insubordinate to use as much safety equipment as you feel is necessary, but to just refuse work as you suggest is considered insubordination. I would hate to hear of someone loosing their job by just refusing work before all of their options are explored.

I know from experience how difficult it is sometimes to protect workers as discussed in the origin of this thread. Just a friendly word of caution to think before we act

[tramp67]

Careful inspection of the energized cables, along with applying any protective barriers, such as an insulating blanket, and if the person working near the energized cable requests it, some 3/4" plywood over the covered energized cable should give you a reasonably safe work area. There's always some inherent risk to our trade, we just need to find ways to minimize the exposure to the risks. We can't just go ahead and de-energize everything we come across. The hazards our trade presents, and the knowledge to minimize the risk and work in a safe manner in the vicinity of hazardous conditions is what we are trained for and paid to do. If everything was done de-energized, we might as well give all the work to narrowbacks and operating engineers.
It seems like one person gets all worked up about something "unsafe", and then everyone goes into panic mode, especially with underground cable. It's a normal practice to work in underground vaults with energized cables, we work on padmount transformers with energized primary in the enclosure, we work on overhead lines next to and on energized primary circuits. We manage to do it safely by minimizing the risks and exposure to the hazardous voltages. The same can apply to working in a trench with both energized and de-energized cables. The biggest issue is to verify that the cable we are about to work on is indeed de-energized and grounded, usually the best method is with a cable spear or remotely operated hydraulic cutter. Covering the energized cable with a blanket, and a sheet of plywood or a fiberglass pad, if you have one, should be more than sufficient to protect you from the energized cable.
I've noticed that a lot of linemen tend to be very complacent about pad mount equipment, and the lack of wearing PPE when working on and around this equipment. There's a much greater hazard to a worker standing in front of an open padmount transformer with the steel enclosure acting as a blast wall, aimed directly at the lineman, than the hazard of working next to an energized cable in a trench, open to the great blue yonder.

[Bull Dog]

I did not see your previous post, but I guess the point I was trying to make was too subtle.

When dealing with management there is sometimes a fine line between refusing work for safety concerns, and insubordination. It is not insubordinate to use as much safety equipment as you feel is necessary, but to just refuse work as you suggest is considered insubordination. I would hate to hear of someone loosing their job by just refusing work before all of their options are explored.

I know from experience how difficult it is sometimes to protect workers as discussed in the origin of this thread. Just a friendly word of caution to think before we act

Management can kiss my patutie. Its my life and I will do it the safe way period. More than a few times I have had to tell my manager in no uncertain terms its not safe and I am not doing it. Never had a problem. We had a guy digging in a ditch with energized cables and he got a blast. Its just plain stupid to do it period. Insubordination that is a joke right? You in management cause you sound like one.

[Lineman North Florida]

Careful inspection of the energized cables, along with applying any protective barriers, such as an insulating blanket, and if the person working near the energized cable requests it, some 3/4" plywood over the covered energized cable should give you a reasonably safe work area. There's always some inherent risk to our trade, we just need to find ways to minimize the exposure to the risks. We can't just go ahead and de-energize everything we come across. The hazards our trade presents, and the knowledge to minimize the risk and work in a safe manner in the vicinity of hazardous conditions is what we are trained for and paid to do. If everything was done de-energized, we might as well give all the work to narrowbacks and operating engineers.
It seems like one person gets all worked up about something "unsafe", and then everyone goes into panic mode, especially with underground cable. It's a normal practice to work in underground vaults with energized cables, we work on padmount transformers with energized primary in the enclosure, we work on overhead lines next to and on energized primary circuits. We manage to do it safely by minimizing the risks and exposure to the hazardous voltages. The same can apply to working in a trench with both energized and de-energized cables. The biggest issue is to verify that the cable we are about to work on is indeed de-energized and grounded, usually the best method is with a cable spear or remotely operated hydraulic cutter. Covering the energized cable with a blanket, and a sheet of plywood or a fiberglass pad, if you have one, should be more than sufficient to protect you from the energized cable.
I've noticed that a lot of linemen tend to be very complacent about pad mount equipment, and the lack of wearing PPE when working on and around this equipment. There's a much greater hazard to a worker standing in front of an open padmount transformer with the steel enclosure acting as a blast wall, aimed directly at the lineman, than the hazard of working next to an energized cable in a trench, open to the great blue yonder.

Not to start a contest with you tramp but I would hate to be the one to test out that plywood method if a cable faulted under my feet,especialy a cable that had layed side by side over or under another cable that had just faulted, and I sure would hate to be the one to get in the ditch and do that close inspection. I understand about all the hype and everyone getting worked up about stuff being unsafe and all,I deal with it all the time, but lets face it this aint overhead where you can spot a broken tie wire or a badly flashed insulator while working out of an insulated bucket truck, I think these guys have a legitimate concern, I am all for doing all you can hot, I'm old school, I just don't think this is one of those times, did'nt say it could'nt be done just don't think it's worth the risk.

[tramp67]

Not to start a contest with you tramp but I would hate to be the one to test out that plywood method if a cable faulted under my feet,especialy a cable that had layed side by side over or under another cable that had just faulted, and I sure would hate to be the one to get in the ditch and do that close inspection. I understand about all the hype and everyone getting worked up about stuff being unsafe and all,I deal with it all the time, but lets face it this aint overhead where you can spot a broken tie wire or a badly flashed insulator while working out of an insulated bucket truck, I think these guys have a legitimate concern, I am all for doing all you can hot, I'm old school, I just don't think this is one of those times, did'nt say it could'nt be done just don't think it's worth the risk.

If the energized cable looks like crap, or has old splices in the vicinity, I'd definitely be leery of it. But if, after a good visual inspection of the energized cable, it looks in good shape, I personally wouldn't have a problem with being in the same trench with it. Certainly would use a remote cutter to make sure the cable being worked on is de-energized. I just don't understand why it would be such an unsafe thing to do, when nobody ever questions working in underground vaults with multiple circuits of primary cable, many cases lead, and the majority of the cables are spliced. In a vault, if something blows up, you might as well kiss your @ss goodbye, and you are almost never going to find a utility that will allow you to de-energize all the cables in a vault.
Sure, if it's a fairly easy outage to take on the adjacent cables in a trench, and you aren't going to be putting many customers out of power, by all means try to kill everything in the trench. I guess it would have to be a judgment call, as we all know no two jobs are alike. But I do feel that the risk can be minimized with a little bit of effort. Just my opinion.

[Lineman North Florida]

If the energized cable looks like crap, or has old splices in the vicinity, I'd definitely be leery of it. But if, after a good visual inspection of the energized cable, it looks in good shape, I personally wouldn't have a problem with being in the same trench with it. Certainly would use a remote cutter to make sure the cable being worked on is de-energized. I just don't understand why it would be such an unsafe thing to do, when nobody ever questions working in underground vaults with multiple circuits of primary cable, many cases lead, and the majority of the cables are spliced. In a vault, if something blows up, you might as well kiss your @ss goodbye, and you are almost never going to find a utility that will allow you to de-energize all the cables in a vault.
Sure, if it's a fairly easy outage to take on the adjacent cables in a trench, and you aren't going to be putting many customers out of power, by all means try to kill everything in the trench. I guess it would have to be a judgment call, as we all know no two jobs are alike. But I do feel that the risk can be minimized with a little bit of effort. Just my opinion. He stated Tramp in his original post that the energized cable had faulted before because there was a splice next to the faulted cable, that would be one of my reasons for concern, I agree with you about the vaults and manholes, had a dispatcher close a breaker in on me one time on a faulted trayer gear while I was putting the pump in the hole to pump out the water and it was'nt pretty and I was lucky, that's why I like OVERHEAD.

[Mike Honcho]

Ryan, I have to assume this is a lateral feed, with one source so you are unable to loop the other phase's and open and Isolate the phases in the ditch. In the first place you should not be even thumping your faulted cable in a ditch with other energized cables are present, you could thump into a cable next to it, it could fault, and return that fault current to your thumper and blow it and you up. The foreman in this case is way out of line, the journeyman in this case are way out of line. Check with your Thumper manufacture, they will help with your case, also you must have a EP zone with grounding mats, and you must have your primary neutral macked out to spice any cable.

[mainline]

With a faulted cable we often thump it and that will definitley make the faulted cable apparent when it is dug up. The majority of them are burned right off. I'm kind of puzzled how you jumper out the neutral on a jacketed primary cable with out handling it. Maybe I misunderstood. When we have live cables that we are sectionalizing to work on. We isolate the cable that we are going to cut into, test tag and ground both ends. Then we use a impulse phase tester to identify the cable. After the cable is identified we drive a ground rod and use a piercing ground before we cut the cable. At this point I would feel comfortable working in the trench as long as the other cables are in good condition. If the other cable was known to have faulted recently, or there were splices in poor condition I would strongly suggest getting an outage so the work can be completed. It really is a judgement call on the JLs part, though it is hard argue that dead and grounded isn't the absolute safest way.

[lewy]

Any time we have to dig around energized primary we use a sucker truck to expose the cables ( always under hold off ) . If we are repairing a faulted cable & there are energized cables in the same trench we will isolate, if on a loop feed, if not & the cables appear fine we will take appropriate measures to make the trench safe. If the cable have splices & we do not think they are safe we would make arrangements to have an interuption to change them. Before we cut any cable after we have identifyed it we spike the cable.

[Mike Honcho]

A few thing's, first most of the direct buried cable that is the ground is old and not jacketed, thus the concentric neutral is macked out with a ground that will fit over the cable, you can still spike the cable before macking it because you did not cut it yet. If it is jacketed cable you must strip the outer jacket, mack the neut before cutting. Second, After Identifying, Isolating, testing and grounding your faulted cable, If you choose to ground at both ends, and your concentric neutral is bad, then when making your splice you can make your primary a better path for current return thus you can get in series, because now it becomes the primary neutral for return. A solution is after grounding both ends is to remove the ground and park one end on a isolating bushing, and leave the other end grounded. Third, if you are a journeyman, you can choose to do it as you wish, but you should not put an apprentice in a ditch with energized cable's to have him splice it.

[tramp67]

A few thing's, first most of the direct buried cable that is the ground is old and not jacketed, thus the concentric neutral is macked out with a ground that will fit over the cable, you can still spike the cable before macking it because you did not cut it yet. If it is jacketed cable you must strip the outer jacket, mack the neut before cutting. Second, After Identifying, Isolating, testing and grounding your faulted cable, If you choose to ground at both ends, and your concentric neutral is bad, then when making your splice you can make your primary a better path for current return thus you can get in series, because now it becomes the primary neutral for return. A solution is after grounding both ends is to remove the ground and park one end on a isolating bushing, and leave the other end grounded. Third, if you are a journeyman, you can choose to do it as you wish, but you should not put an apprentice in a ditch with energized cable's to have him splice it.

Most of the faulted cables I have run across that haven't failed at an elbow or pothead have burned themselves in two, jacketed or not. Which makes the process of macking out the neutral before handling the cable an impossibility. A better solution would be to isolate, tag, ground, identify, and spear the faulted cable. Then, with it being in a common trench with other, energized cables, wear the appropriate rated rubber gloves, and you are then isolated from the cable. Preparing and keeping a jacketed cable's neutral macked until you made your final neutral crimps would be very time consuming, cumbersome, and would involve compromising the integrity of the cable and the newly built splice.
I've never had a problem with thumping a faulted cable that was in close proximity to other energized cables, even with them in the same duct. Also have never had problems with thumping through transformers. The manufacturers caution you against using their equipment near energized cables more for liability purposes than anything. Yes, you do have a very minimal chance of a cable burned in two arcing to an adjacent cable, but the energy would be absorbed by the concentric neutral on that cable. Unishield cable might be an exception, since there is no real neutral conductor, the few small strands in this type of cable primarily serve the purpose of a bleed wire for the semicon shield. Fortunately, there isn't that much unishield cable out there, and it pretty much was used in three phase feeder tie applications without much phase imbalance on the load. In which case, you would typically have all three cables de-energized whenever one faulted.

[Ski_Digger]

Just hope your not cutting the cable with short handle cutters, bettter be useing a 8ft cable cutter so your outside the trench. Don't understand why you would do that splice with energized cable in the trench. I can not understand a reason for it.
Sound like time to plow some new cable and junk the old out.
Be safe brother URD is a kill. I have seen cut off energized pri. cable in the ground.
Ski

[tramp67]

Just hope your not cutting the cable with short handle cutters, bettter be useing a 8ft cable cutter so your outside the trench. Don't understand why you would do that splice with energized cable in the trench. I can not understand a reason for it.
Sound like time to plow some new cable and junk the old out.
Be safe brother URD is a kill. I have seen cut off energized pri. cable in the ground.
Ski

Always use a cable spear or remote cable cutter to verify the correct cable is being worked on. I don't think I would want to be at the end of the handles of a manual cutter and accidentally chop through an energized cable!:eek:

[Mike Honcho]

That may be your experience, but that is not the only experience out there. Many faults are not blown into, in fact some are vary small pin hole size that are hard to locate. Yes some are blown into, some are bolted fault's. As far as thumping cable in a energized ditch, I wish I had the pictures to show you what a blown up UG thumper van looks like. As far as thumping cable in conduit, really make's no sense, do you dig it up, cut your conduit, splice then what? A UG slice is not a strain splice, Splice bodies are bulky, how do repair the pipe, why not pull in new? Isn't that what a duct system is for. As far as thumping through transformer's, There are alot of older home's that use the water line as there service ground, There are many horror stories out there like the lady getting dropped while turning on her faucet. As far as splicing in a ditch with other energized cable's in it, Is it done, yes, should it be in my opinion no, Ya talk about rubber glove's, what about step potental. If you have thumped a faulted cable, and have never burned into the other two where you have end up spliceing all three anyway, consider yourself lucky I guess, Alot of the point's I was making in my first post was what should be done, reminder's about bad concentrics, blown up van's, people getting dropped by step potential with out going into to much detail. If it help's some apprentice say no to the Journeyman or Foreman that told him to splice that cable in that energized trench, good, he has no business doing that, he can make that call when he top's out. But to me it is a bad work practice. As I said before do what you want. When thumping the cable, is it AC or DC?

[tramp67]

DC, most of my experience with thumpers are the ones powered by a 12volt deep cycle battery. Same goes for TDR, and highpot testing. DC voltage, equipment powered by a battery on distribution voltage cables. Regarding the conduit question, there's a lot of places out there where part of the cable runs through ducts, or conduit, part of the way, may or may not pass through a vault, and continues on as direct burial, with no elbows or other disconnecting means at the place of transition from conduit to direct bury. Same thing with direct buried running up risers. It isn't the best way, but we don't live in a perfect world, and some utilities will run a single phase riser up the same Uguard or conduit as a three phase, or another, single phase riser. Side by side, one energized, one de-energized and being thumped. Prudent thumping dictates using the lowest voltage and current necessary to cause breakover, thereby minimizing further stress and damage to the cable, also minimizing the possibility of damaging another cable. Obviously, there's more than one way to tackle any project, and company safety policy has a lot to do with it, along with the many variables to any job, and the experience of the crew, along with the equipment available.

[tramp67]

A thumper van? Wow, that brings an image to mind! Picture a brown chevy van, with the tinted bubble windows on the sides, the interior wall to wall, floor to ceiling brown and gold shag carpeting, a striped mattress on the floor, covered with stains from who knows what....:eek: Sorry, LA, I just couldn't pass that one up!!!:D

But really, always new things to learn. A thumper van sounds like a WWII vintage piece of equipment, I think I saw a picture of one in about the 3rd or 4th edition of the Lineman's and Cableman's Handbook. Do you really have any equipment nowadays to test underground primary cable that requires it's own van? It would be interesting to see, as it's something I've never run across yet.

As far as thumping through transformers, the few thumper manuals that I've actually read cover to cover state that it is perfectly safe to thump through transformers, and it is basically a waste of time to disconnect each transformer, stand off the primary, move the thumper, .......

Back to the AC or DC question - I guess maybe that's where the thumper van comes into play? I never tested or thumped cable using AC, and really don't understand how it would work well or the reasoning behind it, not to mention the tremendous stress it must impose on a cable. After all, underground primary cable is basically a long capacitor, and to subject it to an alternating current under fault conditions is proven by the cable manufacturers and EPRI to be very damaging to the cable, much more so than the DC current. Maybe that's where the exploding thumper vans come into play? I don't know everything, never claim to, but this one just seems too far out for someone to be doing, with all the technology out there today.:confused:

[lewy]

We always TDR the cable before we thump & we will TDR through transformers but once we have a good idea where the fault is ( TDR will tell you approx how far away fault is ) We will then thump the cable between the open points, do not see why you would thump through a transformer, if your thump-er is DC would it not go to ground through the winding? I have never heard of a thump-er powered by a 12 volt battery , we power ours either with a cheater cord or a generator. We also put it on a voltage low enough to just jump across the fault , I have thumped a lot of cable & when standing over it you can sometime hear it & feel it & have never had or heard of a problem with step potential.

[Mike Honcho]

I have worked for four different utilities, They have all had thumper vans where the equipment is installed in them, new and old, there are also portable unit's same equipment, portable unit's has a battery back up for remote location's, but all are run of a 120V inverter or portable generator, portable generator's are alway's the last resort because they are loud, hard to here the thump. As Lewy states you scope it in the Arc Reflection Mode, Yes you can see through transformers, but you have laterals alot of times, fault indicator's if installed should have already been looked at prior as part of the trouble shooting. As far as AC or DC, Your newer devices have a DC HI POT feature, you can also use you phasing set with the DC hipot adaptor for trouble shooting, but you should Isolate lightning arrestor's and transformer's when doing so. When putting your thumper in the direct mode or Thump mode to hear your fault it is actually an AC Voltage with a Square sine wave, again check with your manufacture of the thumper being used. I would also reiterate that no manufacture will approve the use of a thumper when eneregized cable's are in the same trench. A utility will not purchase a piece of equipment and say it is alright to use against manufacture's recommendation's. Again going back to Ryan's original post, there was a faulted cable in a trench with energized cable that was spliced 3" away, now to me a couple of thing's could have happened there, either when the first cable faulted, when thumping that cable, it damaged the integrity of the wire next to it, causing it to fault later, or when excavating the first fault they damaged it when digging it up or back filling it with out useing proper fill. There are other example's but that would be my guess. As far as step potental, you must work in place's where your concenrtic neutral is in good shape, again I will state that is not always the case. I have been on many faults where the concentric is completely corroided, as certain soil's are extremely corrosive to unjacketed primary that was plowed in 30 to 50 year's ago. When can you tell if your concentric is bad, when scoping it, your radar dosen't give you a good siganal, even when you try from both end's. If you have thumped a cable, and not isolated your transformer, and not seen light's go on and off everytime you thump, again consider yourself lucky, I have seen it happen, don't take my word for it, talk to your equipment's trainer's, dig as deep as needed, but ask about these question's, ask about step potental. Or keep on doin what your doin, it's your call.

[tramp67]

I have worked for four different utilities, They have all had thumper vans where the equipment is installed in them, new and old, there are also portable unit's same equipment, portable unit's has a battery back up for remote location's, but all are run of a 120V inverter or portable generator, portable generator's are alway's the last resort because they are loud, hard to here the thump. As Lewy states you scope it in the Arc Reflection Mode, Yes you can see through transformers, but you have laterals alot of times, fault indicator's if installed should have already been looked at prior as part of the trouble shooting. As far as AC or DC, Your newer devices have a DC HI POT feature, you can also use you phasing set with the DC hipot adaptor for trouble shooting, but you should Isolate lightning arrestor's and transformer's when doing so. When putting your thumper in the direct mode or Thump mode to hear your fault it is actually an AC Voltage with a Square sine wave, again check with your manufacture of the thumper being used. I would also reiterate that no manufacture will approve the use of a thumper when eneregized cable's are in the same trench. A utility will not purchase a piece of equipment and say it is alright to use against manufacture's recommendation's. Again going back to Ryan's original post, there was a faulted cable in a trench with energized cable that was spliced 3" away, now to me a couple of thing's could have happened there, either when the first cable faulted, when thumping that cable, it damaged the integrity of the wire next to it, causing it to fault later, or when excavating the first fault they damaged it when digging it up or back filling it with out useing proper fill. There are other example's but that would be my guess. As far as step potental, you must work in place's where your concenrtic neutral is in good shape, again I will state that is not always the case. I have been on many faults where the concentric is completely corroided, as certain soil's are extremely corrosive to unjacketed primary that was plowed in 30 to 50 year's ago. When can you tell if your concentric is bad, when scoping it, your radar dosen't give you a good siganal, even when you try from both end's. If you have thumped a cable, and not isolated your transformer, and not seen light's go on and off everytime you thump, again consider yourself lucky, I have seen it happen, don't take my word for it, talk to your equipment's trainer's, dig as deep as needed, but ask about these question's, ask about step potental. Or keep on doin what your doin, it's your call.

Check out this link. Maybe you should talk to your utility about moving into the 21st century in equipment. I have used this particular unit, and similar ones made by Biddle, etc., all battery powered. I have taken them to remote areas on the back of an atv, by boat, and by bush plane, not to mention wheeling them into back lot lines in town. They perform very well, have always been able to locate faults in thump mode, and have had pretty good luck with the TDR capability of these units. And yes, the manufacturer specifically states that their equipment is designed to thump through transformers, as the specs on this link state. The manufacturer rep that I have done training with years back claims there is no problem with using these units to thump near adjacent energized cables. I'm still not sure why you would have an entire vehicle devoted entirely to fault locating, unless it was someone's full time job?? I've never seen any modern equipment large enough to require a van to carry it, not even hipot and ratio testing equipment for station transformers - the equipment for testing station transformers that I've had experience with fits in those neat hard sided "suitcases". Usually seems like the cables take up more space than the test equipment. But, I'm sure there's all kinds of equipment out there that I've never seen or used, just as you must not have run across equipment like this.

http://www.hipotronics.com/pdf/5250brochurenewpic.pdf

http://www.iupcorp.com/iupcorp/iup2003.htm

I'll stand by my experience with thumping through transformers and near energized cables unless I'm working somewhere that a company safety manual prohibits it, as I've never had a problem and have been trained by manufacturer reps that it is an acceptable practice, at least with the types of equipment I'm familiar with. Maybe your truck mounted test equipment does not allow testing this way, it's the stuff you are familiar with. As always in linework, there's always more than one way to do a job, and more than one tool to do it with.

[Mike Honcho]

I do not see anything in that link that recommend's or approve's thumping cable next to energized cable's. I am familiar with unit's like you have posted.
http://www.cablemasterinc.com/product_details_hdw_smartthump.html

I never stated you can not look thru transformer's, I do not know why you would actually thump thru them when in the Direct mode. Loop feed's in my experience have normal open's, fed from different sources, thus only having a partial outage, but I am confussed on your methods, Do you go to your first transformer or switch cabinet, shoot the hole line, then thump it leaving custmers out til you find your fault?

But getting back to the original post, an apprentice splicing a faulted cable with engergized cable's 3"to6" away. If it is your recommendation to thump cable next to energized cable that is your call, if it is your recommendation to splice faulted cable in an energized trench again that is your call, if your supplier recommend's thumping cable in an energized trench with multiple cables, again that is there call.

If my recommendation's are opposite, that is my call. As I stated before do as you see fit.

[Ski_Digger]

Mike H.
Like you said, I totaly agree with ya.
You got to find the fault what ever way a company does it.
Splicing cable with other cables energized in the same trench, Man a lot of bad things can go wrong real fast. I can not see any reason to do that.
We always open and ground on both ends and isolate the cable.
Like you said I also have seen the cable burnt right off and glassed over, or the other end of it just a pin hole in the cable.
If there is three open concentric cables in the trench you could have a lot of current flow in the ground. With two "Hot" you could have a difference path for that neu. conductor.
I have spliced cable were you moved it and the Neu. has fallen apart. That is why we never splice with energized cable in the trench.
What it comes down to is urd sucks builder overhead:)
Work safe and wear your glove.
Ski

[Mike Honcho]

Ya Ski, I have done it myself, did'nt like it, multiple circuit's Sub get away's, I have also seen guy's do it. don't want to take the time to switch it out, But they were Journeyman, not some apprentice.

[linehandjlc]

i was working for a coop (1st mistake)who has a pretty nice urd system (all swithes are under oil) and is 70% u/g (2nd mistake) due to the resort area they are in (3rd mistake). i swapped crews for the first time after six months of being employed moving over to the maint. crew, (which was run by a six year journeyman who hasn't worked anywhere but there and thinks nobody does any linework but there) i knew there were going to be problems when i realized the lack of equipment this foreman had @ his disposal, (most likely because the company dosen't trust him not to destroy it). i was comfortable with my previous foreman recognizing that he was a lineman of 20+ years who had applied himself. he warned me about some of the practices there were not up to industry standards, especially the foreman that i was preparing to rotate to. it only took one week for me to see what he was talking about. what do you all think about a company pulling and snapping elbows then floating them never actually grounding and then working on the cable bare handed, claiming that due to the high resistance here in the mountains it creates more of a danger to ground????? yet this only pertains to their u/g system, their procedure for o/h grounding is legite. i didn't buy it @ all, stood my ground. but, i'm an apprentice who's obviously lacking confidence due to exposure. comments?