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View Full Version : urd question for troubleman and experienced lineman



billfoster67
05-28-2006, 04:11 PM
I was trained as a construction lineman, IBEW. Then went to Edison for a year and a half. I have been with really trained people. And I have learned a lot.

I know about fault current and how to calculate fault current. I know it can damage anything- and make things go catostrophic.

I was on this loop wagon trouble truck. There was an outage on a simple URD loop system. Dip to Normal open. The guy brought no tester with him. I don't think there was too much troubleshooting equipment. He was just plugging into a fault. And did it a few times until he found the right cable.

I told the loop wagon foreman that I really don't think that is to smart. When now a days you can buy a handheld tdr. Instead of degrading all the cans and cable with fault current. I don't want the next guy or myself someday plug in a load break elbow and look like Freddy Kreugger after I do it.

I know its a simple question. But what is the best and safest way of trouble shooting a URD loop with normal open.

At Edison who trained me on the vault systems, we would find the problem, isolate, fix, and switch to get the system normal. If it took us to jump in 15 vaults with a half milliion customers out we would do it.

I need some ammo for argument for this foreman. He says we need to get customers on! This is how we've been doing it for years! Meggering takes too much time! Know one knows how to use the TDR! Just ignorance.

Can some one give me the best way to find a fault without just plugging away. Some advice on how to do it efficiently. I would appreciate it. I am not a URD guy.

Bull Dog
05-28-2006, 05:09 PM
Chance makes a hypot tester that screws on to there phasing sticks. Works real good to find falted cable. We quit using the system you are using there years ago. Like you said too hard on equipment and dangerous. You are right the formans wrong. Check into chance falt testers easy to use and will save lots of time over the method your doing. One of there reps would be happy to splain it all to ya. Now you will also get there lights on faster instead of knocking out half the city which is usually what happens when you start banging the breaker! Yes I am an experienced lineman and TS. Good luck wif that foreman.

grey dog
05-28-2006, 11:20 PM
The TDR is a safe way to go the newer ones are a lot smaller and easier to use.It does take money up front, but the pay back is in time and shortened outage times, longer cable lifetime and less transformer stress. That what to say to the white hats.
Fact is. It is all of those things and safer. With good training, VERY IMPORTANT and PRACTICE. Usually you can pinpoint your fault. Isolate and restore service on a looped system. While the guys with the chance tools will be looking in the bushes and behind fences for a tub down the line. The days of recon by fire should be over.

tramp67
05-29-2006, 12:14 AM
My experience on the ol' loop wagon with a co-op way up North involved throwing the thumper on the suspected loop. You can tell if you are on the right cable, and you are all set to locate your fault in one shot. We thumped through transformers with no problem, and there isn't enough current to harm any elbows that you pull while the thumper is doing its' thing. We had a TDR, but it was on the fritz and spent more time in the repair shop than on the loop wagon. So we pretty much had to rely on the thumper by itself. :)

zapped74
05-29-2006, 09:32 AM
In my part of the world for the most part it is all residental and we go can to can checking fault indacators, resetting and looking for a white target. Isolate between the last red and the first white go to the source dip and plug it in, if all goes well hi-pot with phasing sticks to verify fault then go to the EMC and close in the back half of the loop. Takes time but you or the equipement doesn't get hurt. :D

Koga
05-29-2006, 09:40 AM
On all out going cables. When you get to the transformer where the fault indicator is not showing a fault, open up on each side of the bad cable, close your normaly open and shoot the dip.If you have 6 or seven transformers on the bad side of the loop,start at the 3rd transformer.If its good work away from the dip, if not work toward the dip.

Koga

dirtdobber
05-30-2006, 08:30 PM
about this if your fault burned your conductor into you could always ohm the cables. the thumper is a good way to go or better yet hy-pot works well. just remember all L.as must be off line first before hy-potting or they will blow. when hurricane charlie came thru FLA. we did a lot of closing in on faults to restore as many homes as quickly as possible but hard on the equip we always closed in on a fused dip so with 20 ks fuse. :eek:

LINETRASH
05-30-2006, 11:18 PM
'far as I'm concerned, a sectionalizer is the only way to go. 'least thats what we call 'em.

Say I pull up on a trouble call, loop section out, I dont find any dead critters at the base of the pole. If of course the loop is fed from overhead. Dont really matter.

Lets just say the one is blown. I call the dispatcher and advise him that I have a loop out. Then I get my trusty loop books with the correct adresses for the tx's. (well, sometimes correct)

I'll look at an indicator or two, but they will lie to you if not installed right. And they damn sure dont work worth a shit if the tx or cable was replaced and the crew left 'em in the dirt. (thanks fellas)

Anyway, I get my trusty machine off the truck, a super delux VON brand arc reflection sectionalizer with thumper mode. Its a heavy beast but has turf wheels so it aint to bad.

I go the the halfway point between the normal open and the end thats out and set up.

Using a feed through for elbows or a hot line clamp attachment for live fronts, I shoot it both ways.

When I find the fault, I ask the dispatcher for footages as the machine will give a distance to the fault. If he has footages, I will go to where he thinks it is and confirm.

If he dont have the footages, I'll go ahead and park the elbow where I'm shooting from and refuse the blown switch or normal open, whichever the case may be, and get a section of the loop up.

Then its time to go huntin'. It usually takes me one or two more set ups to find the fault, which I switch out and restore all load.

Sometimes its tricky, 'specially when its actually a bad tx took out the loop, but I always find it.

I do all this without creating fault current which blows off elbows and damages cable and equipment by banging in on a fault.

I'm currenty trying to get a new machine thats on the property which gives tx footages, shows what tx's the fault is between and is much smaller. When I get one I'll tell you all about it, 'less someone else is already using one, and can share.

duckhunter
06-02-2006, 03:37 PM
We will generaly pull the load elbow at the first enclosure past the dip pole. Re-fuse and hy-pot till we find the bad conductor, then we use the thumper. We would not expose conductor or other equipment to the faults, that is how idiots do it, in my opinion.

Bull Dog
06-04-2006, 10:49 AM
They are idiots or just havent figured out how to test cable correctly. We use chance tester. When we find the bad one we Isolate and tag at both ends. Close in at both ends of loop to pick up load and come back in the am to thump and repair. No way do we just try it like we used to! Any utility still finding faulted cable that was should get new Managers to teach them the right way to do it. If its a radial we have to dig it up and splice but most of our urd is looped. By the way i am right across the big lake from you good luck and be safe.

CHICAGO HAND.
06-04-2006, 02:21 PM
Just Hi Potted A Cable At The Pole The Othor Day All Three Tested Good Closed Them All In When The Last One Was Closed It Blew Instantly At The Ring Cut For The Semi. When Will I Learn To Start Wearing Ear Plugs And Use The Extendo To Close.

scammy
06-05-2006, 07:42 AM
I dont touch anything untill I test it with a anologe tester,number one ,you are alreaddy grounded ,number 2 you cant see underground I have been blessed to have such good leaders to teach me , also never trust the salsbury,, it only tells you what you ask it ,,,,,,,,,,,example ,is there 7200? no it says ..............but there is 3000! the salsbury is good for checking nite lites to see if its hot ,,,,,,,,,but not primary ,,,,test with a anologe tester and then ground it ,,,,,,,,,and dont take anyone elses word that its dead ,,,,,too many times been wrong,and the guys dont take it wrong ,,,,they expect you to check again,,,,,,scammy

ScooterTrash
06-09-2006, 09:50 PM
we spent alot of time a couple of years ago puttin in fault indicators, but they will lie. I keep a set of hastings phasing sticks with a hi-pot adaptor. works pretty good

PSE Lineman
06-21-2006, 11:47 PM
Anyone ever heard of arc reflection? That's how we do it in the Northwest.

Special ED
04-12-2008, 05:46 PM
We will generaly pull the load elbow at the first enclosure past the dip pole. Re-fuse and hy-pot till we find the bad conductor, then we use the thumper. We would not expose conductor or other equipment to the faults, that is how idiots do it, in my opinion.


Exactly how ive done it for years.

THE KID
04-15-2008, 10:20 PM
How many of you put URD in conduit from TX. to TX. in a resident neighborhood?

Special ED
04-15-2008, 10:39 PM
Hey Kid:

I know in Louisville they have started installing conduit between cans in new developments. Makes outages and pulling new cable in a breeze! Now if they would just get rid of all them damn subgrades and update their small world prints which they have been working on updating for the past 2 years. lol

johnbellamy
04-16-2008, 12:11 AM
Blown dip fuse: Go to transformer in the middle, park incoming elbow on parking bushing, on the way back to dip, open transformers, pull bayonet fuses and do visual inspection.

At dip pole, test and ground U G, isolate lighting arrestor, unground U G, Use DC hi pot adapter on phasing set to hi pot cable, If cable shows good , reground UG reconnect lightning arrestor, unground U G, energize dip, refuse transformers on the way back to the middle where you have it stood off.

Park cable going out of transformer on a feed through , re-energize transformer, then cut the next piece in half, open and pull fuses and hi pot to the next parked cable, and repeat process, once you have identified bad section of cable, isolate it, and close normal open.

Then use your U G thumper to find fault in cable, If you have the Arch Refection Mode on your thumper, Use it, it won't damage the cable and it will give you a rough distance on your radar to have guys spread out to listen when you put it in the Direct or thump mode.

Fault indicators work great if they are installed correctly, I trust them unless they prove otherwise.

Trbl639
04-17-2008, 03:50 AM
If there is nothing obvious at the dip pole, we bust a cap on it.........if it holds we go home.........if it doesn't, and it is a loop, we check to see if the loop is open where it is supposed to be,,,get another trblmn and sectionalize it and bust a cap until we find the bad section..........if it's a 'one lunger', call for the UG crew or a crew to bring the Thumper..we've got the Arc Reflection Thumper........

some of our newer subdivisions have the primary in conduit xfmr to fmr......all new services are conduit from ped/pot to the meter.........

lewy
04-17-2008, 06:47 PM
If there is nothing obvious at the dip pole, we bust a cap on it.........if it holds we go home.........if it doesn't, and it is a loop, we check to see if the loop is open where it is supposed to be,,,get another trblmn and sectionalize it and bust a cap until we find the bad section..........if it's a 'one lunger', call for the UG crew or a crew to bring the Thumper..we've got the Arc Reflection Thumper........

some of our newer subdivisions have the primary in conduit xfmr to fmr......all new services are conduit from ped/pot to the meter.........

If by blowing a cap you mean refusing that is the old way of doing things, been there done that
real hard on the system sometimes causes more trouble, we also hi pot now with 2 crews you can leap frog much safer, easier on equipment & much quiter

Trbl639
04-19-2008, 10:14 PM
If by blowing a cap you mean refusing that is the old way of doing things, been there done that
real hard on the system sometimes causes more trouble, we also hi pot now with 2 crews you can leap frog much safer, easier on equipment & much quiter

Yep, that's what mean! I'm in a small town...2 trblmn...nearest crew is 35 miles....our UG crew is just a 3 man crew, that works both ovhd and UG..just rotate from the ovhd crew to the UG about every year....if they got no UG work, they are building ovhd............sometimes, especially on a weekend/holiday, a crew might be 2 or 3 trblmn thrown together to get-r-done!!! We just keep the earplugs handy..most of us oldtimers can't hear anyway!!!!!!!

CenterPointEX
05-04-2008, 06:03 PM
We use an HDW radar coupled witha thumper... You first radar the loop... If you have a ground or open at a shorter distance that what the map shows to the open point, you can usualy drive right up to the problem.. We have maps with distances etc. on our loops... If it does not show up with just the Radar, then you thump it with DC at graduating steps until you get it to break over on the open... When it does you can see on radar screen where it goes to ground, then you simply measure the disitance on the map and Isolate that span... If you want you can hook up the thumper to the isolated span get an aproximate distance and then go listen for the thump... x marks the spot... dig here.

west coast hand
05-14-2008, 12:00 AM
A big problem with there system they don't fuses in more then one place and they still us deadbreak elbows. Riser poles with no cutouts. I have spliced 750 and 1000 potheads and no cutouts on the poles, so yes you have to go to 10 places to isolate load. you can also megger or hypot the cable to find faults.

Mad Jack
05-28-2008, 12:47 PM
Plugging an elbow into a fault is a good way to meet your maker (dead) or put you into a position where you wish you had (burned). Get the customer on as fast as possible is great. But if the lineman (troubleshooter) is injured how much longer will those customers be without power. This isn't a race, do it safe or don't do it at all. We normally us fault indicators on our urd with some of which have an extention (fiber optic) to bring the light to the outside of the cabinet. All one has to do is drive down the line and where the blinking lights stop is where the trouble section is found.

Trouble in Texas
06-14-2008, 10:29 PM
Most of our xmers don't have fault indicators inside them, so depending on the size of the loop, which can be from a few to around 20, we'll divide the loop up in half or thirds and throw out a few fault indicators then close the fuse. We'll go check our indicators and usually narrow the hunt down to maybe 3 or 4 xmers, then we'll put indicators in the last few xmers to find out where the problem is. Lift on both sides of the fault, tag xmers, close the n/o and fuse. Most of the xmers in Fort Worth are in backyards with gates locked and maps with wrong information, but a lot of the new subdivisions have the xmers installed by the curb.

west coast hand
06-16-2008, 10:52 PM
I work on edison property for years as a contractor and we always meggered or fault guarded the cable after isolating cable. people that have never worked on edison property its very different system pothead poles with no cutouts almost all elbows deadbreak and maps almost always wrong and its so overloaded most 750 and million cable average 400 to 500 amps and alot of lead and old cable.

Cheezer
07-14-2008, 10:36 AM
There are many ways to troubleshoot urd and it's up to the troubleman. We either set out indicators or split the loop and then we try a fuse. Hard on the system-you bet, but that's the way they want it. Nothing like throwing a 200E into a fault and getting everybody calling in off of that feeder! I don't like throwing bigger fuses into a fault, so I'll try the first piece and hy-pot the rest of it. On 19.9 loops, which can be 30 tubs before the normal open, we sometimes use the oil switches to test the cable. Again, very hard on the equipment, but that's the way it's done here. We had a TDR on loan from somewhere but it was very unreliable. According to some of the posts this may seem like caveman mentality, but this is the way it's always been done here, and I don't see it changing anytime soon.

PSE Lineman
07-20-2008, 12:59 AM
You come up to a term pole or switch can and the fuse is blown on the 1/0 concentric cable. Call for the arc van and 2 more bodys. Go to the first vault with a latteral and test all 3 ways from there. ( testing and grounding is a given here) You thump one direction and listen for the "snap" of the thumper. If it "ticks" it is not that direction. When you hear the snap, you put the thumper into arc mode, turn on the arc reflection box and it will read the length to the next open (end of that line, not to the fault) Then you push the next button, thump it once in arc mode and that tells you the length to the fault. Then you have your pals go the distance and listen for the thump on direct mode, they mark the spot, you isolate, pick up as much load as you can if not all of, then call a crew to dig it up and fix it. None of this shit of leap froggin, hi-pottin' and pulling bayonet fuses. Every once and a while you have to "bust a cap on it" to find out which way to even head when there are more cables than you can count on your fingers and toes. That would be in a switch cabinet. They won't even let us have 200 e fuses. All we have are 150 and smaller. Thats the way you do it, money for nothin' and the chicks are free!!!

Trbl639
07-20-2008, 03:15 PM
When we get there, and there is nothng obvious at the dip, we just bust a cap on it........if it doesn't hold, we call for back-up and try to sectionalize and if we can't get the customers back on, we call for the UG crew----or whoever they can round up.......and we go from there.

When sectionalizing..we never plug-in hot..we pull it off, unplug the elbow, park it, and close the dip..until we find the bad run.......

And MY KEEPER just called and I gotta go on a TRBL call:mad::mad:

JPSURF
09-17-2008, 04:38 PM
I work on edison property for years as a contractor and we always meggered or fault guarded the cable after isolating cable. people that have never worked on edison property its very different system pothead poles with no cutouts almost all elbows deadbreak and maps almost always wrong and its so overloaded most 750 and million cable average 400 to 500 amps and alot of lead and old cable.


Who do you work for?

JP