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4967
10-03-2009, 09:08 AM
As a troubleman, the company I work for gets calls on underground lines of no power. The dispatchers sent me out to find the cause. I normally work alone. After looking around the riser pole, and finding no cause, the dispatchers will tell me to check existing or to install fault indicators. Please note : I am not told to open /or break the line . Then I'm:confused::confused: told to shoot the fuse. My questions are: How safe is this? What does OSHA say about closing in on a 95% or greater chance of the fault? What do other companys do?




















my questio













as a troulb

Pootnaigle
10-03-2009, 11:56 AM
Installing fault indicators is no big deal and they should be present in every transformer lokkin at the next transformer in the circuit.. If you get a flag it simply means fault current passed thru the indicator.At some point you will see one indicator with a flag and the next one normal. Your fault lies between these two.And you must always bear in mind that the fault could be a transformer rather than a faulted cable.
The only other method I am aware of is to isolate every transformer . refuse the lateral and start pluging them in one at a time until you blow the lateral fuse again. This process can be quite lengthy and is less than desirable. If you have lots of URD construction I would try and push for fault indicators to be installed at the same time the transformers are put in service..
You didnt mention what primary voltage this was But On voltages of 20 kv and higher I would feel safer with at least 2 men being involved with the actual switching.

gritter
10-03-2009, 09:25 PM
For us it all depends on what the riser fed ,Padmount,or under ground development Weather conditions also If its busy theyll ask us to refuse it and give it a "bump" Ear plugs and extendo stick comes out.if she blows back at ya then help comes out Then we start shootin trouble.we'll never open a vault ,pad mounts,or man holes with out help.
We have closed a gang switch in testing for a fault,with help.If it dont feel right dont do it and ask for help
stay safe

lewy
10-03-2009, 10:57 PM
As far as I am concerned any time you are trying to find a faulted primary cable it should be a minimum of 2 men. When I first started we would open up half way & try it, but this is very hard on equipment. Now we will Hi-Pot the cables or sometimes use a TDR. When Hi-Poting we will try & have at least 4 men then we can leap frog.

thrasher
10-05-2009, 09:57 AM
We will ride out the route of the line and look for a dig-in or someone who has backed into or over a padmount. If we don't see anything then we will try the fuse once just to make sure it didn't blow from a lightning surge or age/load melt it. If it blows then call a second man to bring the TDR out and check the line. BTW we have fault indicators any where the line splits, but not on straight in and out transformers, so that we can tell which section to test. Anywhere we have more than three transformers we install a loop-feed with a normal open point. This way most of the time we can get everyone on and then repair as planned work.

T-Man
10-05-2009, 12:19 PM
We'll close into a cable with a suspected fault but we do it from a distance, with extendo sticks, Now that we use fault indicators ( FCI ) we have them on the line to begin with so we can check them first like Poot discribed. We are now installing High Volt LA's on our 14.4 system so lightening will drain off rather than blow a hole on the last open terminator (supposed to anyway) In a loop with an open point we would do the first checks and try the fuse if it went and the FCI's showed the direction of fault then we would isolate, If there were no FCI's we would put them in and try it to find where. If there were none we split the section in half try again if the fuse held we would rectify the remaining cables one at a time till we found the fault. Two men for most of the switching part maybe one man to try the first fuse.

Closing into a fault is something we as Linemen will do wether we want to or not, so every time we go to close a fuse we need to be prepared for the blow. get distance, use current limiters take time to be one step a head of what may happen. Not thinking about a possible blow can get you in a lot of trouble.

Work smart and safe.

MI-Lineman
10-06-2009, 10:27 PM
We have trouble shooters do "emergency switching" and even "operational" switching alone. I don't agree but thats our policy. We can usually get help if we want it though. As for fault indicators and hipot adapters, I've had both lie either way. I will say the hipot on our von thumper works very well. We usually isolate at the first switch point and try the riser sometimes with a smaller fuse. If it holds then we put the correct fuse back in and start plugging in sections. I haven't seen a bad tub blow a riser yet as that's what the fuses in the tub are for. I've had guys try to tell me the tub did it but after they change it out and the riser still blows they figure it out!:rolleyes:

Underground circuits work just like overhead. The tub's bad....the trnsfrmr fuse will blow(if fused correctly) not the lcp behind it. Although our "BRILLIANT" engineers started drawing up single trnsfrmr spurs with a solid fuse(100amp) at the tub and the actual rated trnsfrmr fuse at the road!:confused: It only took a couple of lighting strikes and tub change outs for them to learn!:D

Figurehead
10-07-2009, 01:02 AM
We don't have alot of fci's in our system but will check what's there. Usually the riser's blown so we'll isolate it at the first pot/sectionalizer and close in. Now that primarys available we isolate each succeeding run and use phase sticks with adapters to identify the bad run. Kind of a pain to jump ahead, park, come back and test but it always works and works well. Rarely does someone close into a fault and then it's usually an "oops". Once the bad run is found, park, tag, close the loop up to it and go home. We''ll locate the fault with a VON, and excavate and repair.

JUS
11-26-2009, 12:11 AM
4967-
If there are fault indicators, Go to the last flagged indicator. The issue will be between this indicator and the next one. Isolate this span and restore power. Hi-Pot cable.

If there are no indicators, you will have to go to the middle transformer and stand off the out going phases. Shoot it. If it holds, split the remainder and repeat until you find the bad span. Then isolate it and Hi-Pot.

As far as closing in on a fault, wear your PPE and find yourself under your hard hat.

44kv
11-29-2009, 09:43 PM
fault indicators are ok we have alot of them but they lie or the last man out there 3am on saturday morn didnt reset the damn things. So we put a 3amp fuse in it and close in the xformers untill we find the bad run and all our underground primary and secondarys are in condut so its just pull one out and pull another in. But all are primary is loop feed so we can get everybody back on and leave it till a reg work day

T-Man
11-29-2009, 10:05 PM
Our permanant FCI's reset them selves once current passes thru them, after an alloted few minutes. So if the fuse is blown it's easy to find the fault, but if we have a momentary they don't help much, They will reset . . .

44kv
11-29-2009, 10:10 PM
damn i wish ours did, i guess we got the cheap ones lol!

T-Man
12-03-2009, 08:06 AM
Some of our FCI's are SEL ( Schwietzer) and others are Cooper. They reset on voltage in most cases I think I said current in another post. We also have some temporary FCI's our troubleshooters carry when they want to test energize a section in trouble, they place them to split the section up and re energize into the fault, then check the results to reduce the outage time. They isolate the troubled area and restore all that can be, then they take the tempprary FCI's down to use on another outage.

PA BEN
01-21-2010, 09:44 AM
If you don't have a Hi-Pot tool you can use a fault tamer cutout door.
http://www.sandc.com/products/faulttamer/default.asp
Always two people, look over the riser, bad lighting arrester? animal got into it? Isolate cable, you can pull the bayonet fuse's, isolate at the middle transformer after you pull the fuse's. Test the cable and move on from there.

MI-Lineman
01-21-2010, 04:48 PM
If you don't have a Hi-Pot tool you can use a fault tamer cutout door.
http://www.sandc.com/products/faulttamer/default.asp
Always two people, look over the riser, bad lighting arrester? animal got into it? Isolate cable, you can pull the bayonet fuse's, isolate at the middle transformer after you pull the fuse's. Test the cable and move on from there.

What? No mere BOOM BOOM?:eek:

500 KVA
01-31-2010, 02:45 AM
There's a portable unit called an easy restore that uses DC current/radar to TDR and hi-pot an U.G. cable. It will shoot through as many padmount transformers that there is on that run of cable. NO ISOLATING SECTIONS OF CABLE! It will show you every splice and transformer on that cable run. It will tell you how far along that run those objects are. It will also tell you where your fault is located.

Fault indicators cannot be trusted because you don't know if they were reset. The automatic resets can malfunction easily, and not reset. Phasing sticks misread, saying there is a fault quite frequently when there is no fault.

Closing in on a fault is risky business. It damages good sections of cable at a minimum. Be cautious about finding a fault because I have seen two seperate fault locations in a single section of cable at the same time. One causing a weakend spot to go bad simultaneously with the other.

I guess safe and accurate fault finding depends on how much money your company is willing to spend. Cheaper to isolate and give her a one shot test.

PK270
03-07-2010, 04:25 PM
500 - this unit works nicely. Dont have to spend most of the night with spots in your eyes or ringing ears. TDR's have come a long way in the last couple of years.

Liledgy
03-08-2010, 03:08 PM
My first 20 years were spent at a very large utility doing overhead urd and some transmission. . Anyway we always used feedthru bushing to hipot cable w/ sticks and then install elbow grounds. We also would use feedthru's to phase cable together before closing an open, if we were just going to park an elbow we still could use single parking bushings ( standoffs). I've long since moved on to other places but the place I work at now uses single bushing standoffs. When they hipot or phase together they pull cable off bushing, pull it back so probe is faceing up and another lineman sticks the female adapter of testing sticks into elbow. The other stick will then go into the transformer to hipot or to phase cable together. To me this is the most ridiculous work practice they have. The sad thing is that feedthru bushing are available. I refuse to test this way since feedthru's are available. My question is what are the practices at other major locations?

book2
03-23-2010, 11:26 AM
In the city we have about 75% underground and have had for a long time and we trouble shoot it, first we Always try a fuse first, then if it blows isolate half way and then try a fuse, if it blows isolate it in half again, then one at a time until it blows again. One troubleshooter will do the two first steps before a second (if available) troubleshooter shows up. Our company has started to use the radar machines as 500 KVA talked about, they work most of the time. But as the underground ages the neutral breaks down and the machine doesn't work as good. We have a lot of laterals of 10 or more transformers before the normal open which can be up to 1500ft. or more. We always have ppe in place and double stick or long stick when trying the fuses. we have a 4ft. shootgun for our single phase xfmrs, which allows switching in confined spaces, yes we have all parts and equipment blow at one time or another but with ppe in place 99% of the time you walk away with another story. It takes a long time working single and three phase undergroung outages to pick up some of the small things that come with it.
There are more things to discuss regaurding underground but my typing is limited. Be safe and use your ppe!

Troubleman72
05-11-2010, 09:48 PM
i ama troubleman for first energy we are installing fault indicators on all underground systems . first the fault indicators must see afault min of a 3o-35amp fuse or they may or may not see the fault . the fault indicators blink for approx 8 hrs till reset . i will get back to you about the make and model .
we also use fault indicators on overhead we use a couple of differnt models
the one we use the new ones see the fault and blink red and when then power is restored they blink yellow and red .these are led lights and very bright .now having said this the yellow is blinking for 8hrs when the power is restored and the red will still blink to show where the fault is also for 8hrs then the red will reset and continue to blink yellow

Troubleman72
05-11-2010, 09:56 PM
we run a one man touble crew when we get to the scene and the riser fuse is blown protocall is to go in about half way and pick a transformer or dogbox and install a fault inicator and also install the fiberoptic lead also so you dont have to take alot fo time opening the transformer . then go back to the riser and with dispatch's ok refuse and try . then if opens back up
call crew in and theywill thump the cable with the wizard and mark the spot dig up and repair..

jozmo
05-12-2010, 12:14 AM
My outfit had fault indicators installed on almost everthing . S.O.P was to try a fuse first . If it blew start checking fault indicators.

MI-Lineman
05-12-2010, 09:32 PM
we run a one man touble crew when we get to the scene and the riser fuse is blown protocall is to go in about half way and pick a transformer or dogbox and install a fault inicator and also install the fiberoptic lead also so you dont have to take alot fo time opening the transformer . then go back to the riser and with dispatch's ok refuse and try . then if opens back up
call crew in and theywill thump the cable with the wizard and mark the spot dig up and repair..

Never seen an indicator with a "fiber optic lead?" I take it's to hang under the door so ya don't have to open and close constantly????

Trbl639
05-13-2010, 01:06 AM
Never seen an indicator with a "fiber optic lead?" I take it's to hang under the door so ya don't have to open and close constantly????

Some of the new ones we were getting right before I retired had a fiber link...drill a hole in the side of the door and the end slipped in it, so you could see it.............most of my troubleshooting them was sectionalize, and bust a cap until you found the bad run..........They're still doing that cause only the newest UG areas got the fault locaters:)

FourQed
12-06-2010, 04:52 PM
Where I work URD Primary faults are generaly worked alone. It does not matter weather it is UG pole or switchgear. Go to first transformer and check for targets. If none use portable cable tester and test back to pole or switchgear. If you have a target tripped go to next transformer until faulted cable is found. Our cable tester shoots 12kv DC voltage through cable and will tell you most of the time when the cable is bad. On UG system will need at least two men to work manholes.
Live testing is usually last resort, if targets not working properly. Split loop in half and try fuse. If it blows open back up, close open point on other end and keep going backwards toward pole or gear.

Meat1
04-08-2011, 02:59 PM
We use fault indicators on the incoming cable in the tranx. They work well if they are reset after the trouble is isolated. Where I am it's very common for a troubleman to switch and isolate the trouble by himself. If the project feeds out if a cubicle we have flashing fault indicators and usually mechanical indicators on the cable itself. Our troublemen switch 3 phase and single phase alone all the time. Most underground faults are permanent so the troublemen know that it's a waste of time to just start busting fuses and trying to walk the trouble back to the normal open point. We are all pretty good about resetting the flags on our fault finders. There are times when we don't have a choice and we have to go through the whole project and reset all the indicators then run back to the pothead and bust a cap to see where we need to isolate but more often than not we can trust the flags. I would have to say that the troublemen where I work are some of the best at ud switching that I have ever been around.

hotwiretamer
05-04-2011, 10:22 PM
My first 20 years were spent at a very large utility doing overhead urd and some transmission. . Anyway we always used feedthru bushing to hipot cable w/ sticks and then install elbow grounds. We also would use feedthru's to phase cable together before closing an open, if we were just going to park an elbow we still could use single parking bushings ( standoffs). I've long since moved on to other places but the place I work at now uses single bushing standoffs. When they hipot or phase together they pull cable off bushing, pull it back so probe is faceing up and another lineman sticks the female adapter of testing sticks into elbow. The other stick will then go into the transformer to hipot or to phase cable together. To me this is the most ridiculous work practice they have. The sad thing is that feedthru bushing are available. I refuse to test this way since feedthru's are available. My question is what are the practices at other major locations?

We always use feed-thru's with our sticks when checking for bad cable.

reppy007
11-11-2011, 09:59 PM
Usually osha wont get involved unless theres a fatility,and i woudnt think they have anything to do as far as to shooting a loop or not.This i do know,if it blows or before getting on,anything you must get a urd switching order,that is one thing that will have to be shown if theres a serious accident.The decision to close or not is up to you,this is why you are working alone,you have that authority to make that decision.What happens next is also up to you,split the loop in half,pick up only the first span,or just pick up 3 or 4 pots.Everyone has a different approch,and theres alot of experienced urd guys on this website.A 12 kv loop has a greater chance of holding,while a 19.9 loop has a greater chance of blowing,use the method that you choose.Ive been there ,working alone on loops,sometimes couldnt get help due to the others were trying to get circuits on.Ive had lots of experienced though,gotten used to it all.But i can see that you are fairly new,due to the question of shooting or not,is the company your working for short on hands,or are they pushing the younger guys to work those positions?As far as fault indicaters go,ive never seen anyone install them on a loop that was out,sure when the loop is made up,ive seen that.Seen them installed on mostly loops that are hot.And havent ever seen a 1 man carry fault indicaters and told to install on a loop that is out due to trouble,most times he would locate and fix the fault,then get the lights on.

hotwiretamer
11-12-2011, 10:49 AM
Usually osha wont get involved unless theres a fatility,and i woudnt think they have anything to do as far as to shooting a loop or not.This i do know,if it blows or before getting on,anything you must get a urd switching order,that is one thing that will have to be shown if theres a serious accident.The decision to close or not is up to you,this is why you are working alone,you have that authority to make that decision.What happens next is also up to you,split the loop in half,pick up only the first span,or just pick up 3 or 4 pots.Everyone has a different approch,and theres alot of experienced urd guys on this website.A 12 kv loop has a greater chance of holding,while a 19.9 loop has a greater chance of blowing,use the method that you choose.Ive been there ,working alone on loops,sometimes couldnt get help due to the others were trying to get circuits on.Ive had lots of experienced though,gotten used to it all.But i can see that you are fairly new,due to the question of shooting or not,is the company your working for short on hands,or are they pushing the younger guys to work those positions?As far as fault indicaters go,ive never seen anyone install them on a loop that was out,sure when the loop is made up,ive seen that.Seen them installed on mostly loops that are hot.And havent ever seen a 1 man carry fault indicaters and told to install on a loop that is out due to trouble,most times he would locate and fix the fault,then get the lights on.

The problem with test-closing on half the loop is in our district it will sometimes bump the rest of the circuit, and the company don't like that.
Once our troubleman figures it to be a bad cable, others are called out to expedite getting the lights back on by testing, and switching/isolating the cable.
Our common practice is to energize the first piece of cable, and start our testing from there. Yes, we can still bump the circuit if the first piece is bad, but that's just the way we do it normally.

reppy007
11-12-2011, 11:34 AM
The problem with test-closing on half the loop is in our district it will sometimes bump the rest of the circuit, and the company don't like that.
Once our troubleman figures it to be a bad cable, others are called out to expedite getting the lights back on by testing, and switching/isolating the cable.
Our common practice is to energize the first piece of cable, and start our testing from there. Yes, we can still bump the circuit if the first piece is bad, but that's just the way we do it normally.

Thats interesting,that once he finds the bad cable,he just energizes the first span,still alot of work for a one man.I know different areas have different ways,and that is ok.We dont like operating the circuit either,but when closing a loop its just another common thing that might happen.Again it all depends on where and when the urd is out,sometimes we might have 5 loops out,sometimes 25 out and sometimes more.So basically they prefer us to give it a try after a storm.As for the troubleman,if he's alone,that makes his job more diffucult,Another guy working with you is a blessing ,ive heard dispatchers try to control the situation from their desk,and its a shame when a lineman will let them decide on what the lineman shall do or not do.

hotwiretamer
11-12-2011, 12:00 PM
Thats interesting,that once he finds the bad cable,he just energizes the first span,still alot of work for a one man.I know different areas have different ways,and that is ok.We dont like operating the circuit either,but when closing a loop its just another common thing that might happen.Again it all depends on where and when the urd is out,sometimes we might have 5 loops out,sometimes 25 out and sometimes more.So basically they prefer us to give it a try after a storm.As for the troubleman,if he's alone,that makes his job more diffucult,Another guy working with you is a blessing ,ive heard dispatchers try to control the situation from their desk,and its a shame when a lineman will let them decide on what the lineman shall do or not do.

We isolate and energize the first piece of cable before finding the bad piece. We take the chance that the first piece is ok. THEN, we test from that point on, and do it with at least two men, and in most cases three. Storms are different, as we might just test close the loop do to the fact it might have been lightning that took out the dip.
Our dispatch center tries at times to direct the lineman in trouble shooting, I always tell them I will let them know when we have found/isolated the bad cable and give them the info at that point.

rcdallas
11-12-2011, 03:04 PM
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hotwiretamer
11-13-2011, 10:27 AM
That's interesting; isolating and heat the first run from the dip. Here it's different from region to service center I'm finding out as to how it's shot.

Here it's you got a dip fuse blown and see no wildlife or anything obvious it's hi-pot the cable and energize nothing until.

Hi-potting the first piece is probably the best way to go, rather than rolling the dice and assuming it's not the first piece. Have you ever started at the normal open, and worked back towards the riser?

reppy007
11-13-2011, 11:17 AM
To cut your time in half id most likely try at least half the dip,or loop.IF it blows,id no longer have the backside of the loop ,and if it holds id work the backside.I dont remember how many times ive walked out a whole loop and found a fault on the far side,very time consuming,at least here where 99percent of the transformers are in the back easment.Had one that went out really often,customers started getting really pissed,this 12 kv loop had 22 transformers,mostly live-fronts,after being sent there with a van,and seeing nothing,and no luck with the thumper.I called for help,4 other guys showed up,this was only like 4am,so it was dark.We swarm the loop and split up looking inside each pot.We looked at all of them and this one guy goes to the last one,removes the red hood,and sees a possum staring right at him,damn i wished i saw his face when that happened.Seen a few like that with mostly overhead,like a squirrel taking out a over head transformer even when hes dead,due to the wind blowing his tail back into a high-side.

hotwiretamer
11-13-2011, 11:24 AM
To cut your time in half id most likely try at least half the dip,or loop.IF it blows,id no longer have the backside of the loop ,and if it holds id work the backside.I dont remember how many times ive walked out a whole loop and found a fault on the far side,very time consuming,at least here where 99percent of the transformers are in the back easment.Had one that went out really often,customers started getting really pissed,this 12 kv loop had 22 transformers,mostly live-fronts,after being sent there with a van,and seeing nothing,and no luck with the thumper.I called for help,4 other guys showed up,this was only like 4am,so it was dark.We swarm the loop and split up looking inside each pot.We looked at all of them and this one guy goes to the last one,removes the red hood,and sees a possum staring right at him,damn i wished i saw his face when that happened.Seen a few like that with mostly overhead,like a squirrel taking out a over head transformer even when hes dead,due to the wind blowing his tail back into a high-side.

I'm glad we have eliminated most of our live fronts. Critters love those damn things!
Your odds are no more than 50/50 closing in half the loop, so is closing in on the first piece. Dallas is right the correct way is to start at the dip, and test until you find the problem. Most of our URD is in the back easement also. Jumping fences, dealing with dogs, and having to actually go through peoples houses to get to our facilities in the middle of the night sucks!

reppy007
11-13-2011, 01:09 PM
Guess the one that surprised me when i was on a loop working alone was the one in which a transformer was inside of this big storage shed,in which i had to use a barrel stick to switch.We like other utilities have different zones,or areas,and all of them are different,meaning that they all have different proceedures on almost everything.Even seen a dumb-shit switching an elbow with his hand.Guess if you have live-fronts,then you most likely have seen the elbows with the small copper probe,the 19.9 non loadbreaks,they cause problems.Heres one for you,was on a loop in a black neighborhood,with the radar van backed up in the driveway,this was a high crime area,a large houston police officer drives up,pulling his gun on me,thinking we were robbing this house.I mean this guy was big,tall,he didnt even need a gun.Im thinking ,this guy cant be real and inform the other guy in the van,which happens to be black.We go to the front of the van and now the policeman is totally confused and shaking pointing his gun towards us.After giving him the dispatchers number he makes the call,cant blame the guy due that this was about 4am in the morning.

MI-Lineman
11-13-2011, 07:31 PM
How many times have any of you who try the cable first before findin it and repairin it have had to return months or even weeks later to repair the same damn cable maybe a couple of feet from the last bad spot? I've had a couple urd circuits go bad at least 3 times in a month or so in the last 2 yrs only feet form the last bad spot!

Wonder why that is???????:rolleyes: Fault current maybe??????? Ah the hell with it, SLAM'ER HOME!!!!:nightmare:

Pootnaigle
11-13-2011, 09:04 PM
Ummmmmmm I bleve there are 2 different priorities. The troubleman is charged with gettin them lights back on ASAP. The URD Crew that does the repair is more or less charged with protecting the integrity of the cable. I always went to the 2nd Xfmr and looked at the fault indicator if it was clear I shot the first span from the fuse. If Not I followed the indicators until I found a normal and an abnormal, Isolated that from both ends and closed in the fuse then the normal open. I wont say that in a few cases there musta been splices every few feet, But when that was recognized the cable was replaced.

MI-Lineman
11-13-2011, 10:40 PM
Ummmmmmm I bleve there are 2 different priorities. The troubleman is charged with gettin them lights back on ASAP. The URD Crew that does the repair is more or less charged with protecting the integrity of the cable. I always went to the 2nd Xfmr and looked at the fault indicator if it was clear I shot the first span from the fuse. If Not I followed the indicators until I found a normal and an abnormal, Isolated that from both ends and closed in the fuse then the normal open. I wont say that in a few cases there musta been splices every few feet, But when that was recognized the cable was replaced.

Well yeah I guess I gotta remember every area's different! We don't use fault indicators much here! Only if a circuit keeps cuttin out with no problem found? Plus they don't seem to be 100% reliable but then again what is?:rolleyes:

Not sayin guys here don't try it first but it drives me nuts when I'm diggin the same damn wire up over and over and no we aren't quick to change out cable with multiple splices! That costs money you know!:D

reppy007
11-14-2011, 01:42 AM
Anyone that has been around urd has seen these ,sometimes a loop that is short,or a loop thats pretty much straight,like on the same street,what i call an easy loop.Did i say easy,whoops,they can be the ones that seem to be a nighmare,once during and after a storm in which we had loops go out all night,another crew had 8 bad livefronts in the easement.Took them all night on just that one case.Oh heres a question for yall guys,ever had a urd loop feeding off some switchgear that held,i havent,told a guy not to try one,but he did,and it blew back.

Liledgy
11-15-2011, 03:29 PM
I came up useing feed thrus to park the cable, ( at dead front transformers) then use the sticks to hi pot. The place I'm at now bends the cable over at 90 degrees so elbow is now facing the sky, insert the stick with the female adapter into probe then put the other stick in the hot bushings of the transformer, f#%*ed up. The phase cable together the same way!! They then kick the cable below elbow and pull on the stick at the same time to remove it. Oh, and you also need a guy holding onto the shotgun to semi control the cable. This place needs to update their work practices. They shake their head and say I'm f#%*Ed up.

hotwiretamer
11-15-2011, 06:05 PM
I came up useing feed thrus to park the cable, ( at dead front transformers) then use the sticks to hi pot. The place I'm at now bends the cable over at 90 degrees so elbow is now facing the sky, insert the stick with the female adapter into probe then put the other stick in the hot bushings of the transformer, f#%*ed up. The phase cable together the same way!! They then kick the cable below elbow and pull on the stick at the same time to remove it. Oh, and you also need a guy holding onto the shotgun to semi control the cable. This place needs to update their work practices. They shake their head and say I'm f#%*Ed up.

Sounds Freakin' scary! WTF?
They don't believe in feed through parking bushings???

Pootnaigle
11-15-2011, 06:39 PM
UmmmmmmmmmThats skeery dude. Try n bring them folks into the future fore sumbody getz hurt.

T-Man
11-15-2011, 07:32 PM
That is plain dangerous, The outside of the elbow terminator is semiconductor and was one of the contributing factors as to why they flash over on 24.9 before they got the enhanced elbows. Years ago they used to use a neon voltage tester that looked like a pocket pen that had a neon tube in a little window that would glow on hot cable. They would stick it down the throat of the elbow and test the cable dead, but too many guys got flashovers on 4800 volts when the cable was still hot and it didn't take long and our company band them.

We had special clear plastic hoods made to go on the end of our phasing sticks, that would shield the probe from contacting anything while it was inserted into and being removed from the bushing. If I could draw it for you it would be easier to understand but they work great for avoiding drain wires, and weeds or long grass that can sneak up and give you problems

reppy007
11-15-2011, 07:40 PM
I came up useing feed thrus to park the cable, ( at dead front transformers) then use the sticks to hi pot. The place I'm at now bends the cable over at 90 degrees so elbow is now facing the sky, insert the stick with the female adapter into probe then put the other stick in the hot bushings of the transformer, f#%*ed up. The phase cable together the same way!! They then kick the cable below elbow and pull on the stick at the same time to remove it. Oh, and you also need a guy holding onto the shotgun to semi control the cable. This place needs to update their work practices. They shake their head and say I'm f#%*Ed up.
Thought i heard of a million ways to do things,make that one more.Seems like too many steps to troubleshoot urd,actually its easy,and easier when you have a van.Some guys stated that they heated up the first span,i guess that is there policy,ive never heard of that one,but at least someone made a decision.Ive always been sent to find and fix,so that may be why i cant see why they do it that way,butit is what it is.Im not the noisy type,but what company does it that way?I would say that is interesting,but it really isnt.

lewy
11-16-2011, 06:37 AM
I came up useing feed thrus to park the cable, ( at dead front transformers) then use the sticks to hi pot. The place I'm at now bends the cable over at 90 degrees so elbow is now facing the sky, insert the stick with the female adapter into probe then put the other stick in the hot bushings of the transformer, f#%*ed up. The phase cable together the same way!! They then kick the cable below elbow and pull on the stick at the same time to remove it. Oh, and you also need a guy holding onto the shotgun to semi control the cable. This place needs to update their work practices. They shake their head and say I'm f#%*Ed up.

They are just asking to get some one hurt. As far as phasing or testing we use the test points.

creecher874
02-11-2012, 06:07 AM
As far as I am concerned any time you are trying to find a faulted primary cable it should be a minimum of 2 men. When I first started we would open up half way & try it, but this is very hard on equipment. Now we will Hi-Pot the cables or sometimes use a TDR. When Hi-Poting we will try & have at least 4 men then we can leap frog.

I'm a big fan of hi-potting -- don't like having fuses blow back at me. In Dover, NJ, we have a model made by Hastings that serves as both a digital phase meter and a hi-pot (with the optional device). I agree on the man power. With 4 guys leap frogging, you can cover a lot more ground - especially when the weather's not cooperating. The Hastings is a bit quirky though. You have to learn it's idiosyncrasies. I've had it show wire as bad when it was really ok - usually in very wet areas. Also, if you're hi-potting from the riser to the first pot, make sure to cut any arresters off line - they'll give you a false "bad".

rob8210
02-11-2012, 07:34 AM
I had a couple of cases with underground that will make your head shake. First one was in an older subdivision, cable was getting due to be replaced, had it fault in 5 different places in 1 night. Lost use of any possible backfeeds and had to string about 8 spans overhead and build a temporary dip to get the power back on.

Another time I got called in to help a trouble crew to repair an underground loop, right after a 13 week strike. In a run of 17 transformers ( not normal) we had to heat er up span by span, found 5 bad elbows and inserts. Ended up taking almost 24 hours to get all the power back on. The normal feeds had been messed up during the strike and , of course, the maps were not very accurate!!

reppy007
02-11-2012, 09:32 AM
I had a couple of cases with underground that will make your head shake. First one was in an older subdivision, cable was getting due to be replaced, had it fault in 5 different places in 1 night. Lost use of any possible backfeeds and had to string about 8 spans overhead and build a temporary dip to get the power back on.

Another time I got called in to help a trouble crew to repair an underground loop, right after a 13 week strike. In a run of 17 transformers ( not normal) we had to heat er up span by span, found 5 bad elbows and inserts. Ended up taking almost 24 hours to get all the power back on. The normal feeds had been messed up during the strike and , of course, the maps were not very accurate!!

.......Kinda know how that feels Rob........ever get that feeling that you finally have it under control.........deep inside you know that your going to heat it up and head towards the barn.......then go home........when all of a sudden things get worse and your back where you started .........once again.:nightmare:........Ive had some bad ones but not as bad as that..........did know of a crew that had 8 bad pots on a loop after a long thunderstorm.

Hivoltrayman
02-11-2012, 11:21 PM
In BC we might attempt a close on a fuse at a terminal pole by ourselves, anything else we call a second Jman. The other nite, my partner insisted on closing in a fuse which promply blew, but we found the problem in 10 minutes after that thanks to a big black soot cloud on the side of a U/G Tx. I like to call more Jmen and use fault finder direct current sticks and locate the fault that way but a lot more time invoved. We always use 2 Jmen when switing in U/G appratus.

rob8210
02-12-2012, 07:05 AM
Our rules here actually do allow for a one man trouble crew but they are very very limited in what they can do. Most places have a 2 man crew. With underground it has been my experience the more the merrier, if you want to get power restored asap. I haven't had much to do with underground, especially troubleshooting , for quite a while, since I now work for a contractor and almost all the work is overhead construction.

lewy
02-12-2012, 07:14 AM
In BC we might attempt a close on a fuse at a terminal pole by ourselves, anything else we call a second Jman. The other nite, my partner insisted on closing in a fuse which promply blew, but we found the problem in 10 minutes after that thanks to a big black soot cloud on the side of a U/G Tx. I like to call more Jmen and use fault finder direct current sticks and locate the fault that way but a lot more time invoved. We always use 2 Jmen when switing in U/G appratus.

We could try it from the ground with 1man, but we need 2 men to operate elbows. Trying a fuse does work & sometimes you get lucky & find it right away, but sometimes you do not & it can create more problems & it is hard on equipment.

Street Lighter
02-12-2012, 07:55 AM
Always makes me cringe when I hear " Give it a Shot " . That poor lil' cable is 50 years old ! Kinda like me stepping into a kick boxing contest . Ain't gonna last long . :rolleyes: It's no wonder having to come back to a stretch that was just fixed . Had one that once the semicon was stripped back , the insulation was split open underneath . Had to go back a couple foot before we found good wire . This was after an OH trouble crew gave it a " couple shots '.

Do you come up to a blown OH line fuse and without patrolling it out , "Give it a shot " ? I would hope not .

I normally start poppin' tops , looking for whatever . Critters , elbows , connections , contanimation or whatever might could be a problem . As we go opening trf fuses . Takes a little bit of time but once you've made the circuit you've got an open court , so to speak . Now I can set up at a handy spot , Hi-Pot either direction/s , isolate the problem and get the lites back on all without the dreaded "BOOM" in the night . ( Hate when that happens )

Not everyone has a Thumper on site I know and DC Hi-pot might be all you have , just saying that sometimes by slowing down you'll go faster .

Priormilitary
02-16-2012, 09:32 AM
Here at the company I work for that is a 1 man operation. We have fault indicators in pretty much every pad mount transformer so that makes it a bit easier. Once I find the blown fuse, and no wildlife at the base of the pole, I will check the first pot for a target. If I have a target there and it is a long loop, I will split the loop half way and try the fuse one time. that will at least let me know weather the fault is in the first half or second half of the loop and I can get part service back. We have a cable reel tester that we use but it can be quitre time consuming as the cable has to be isolated between both pots to test it. We also have another cable tester thats called the EZ Restore. You can use that while the cables are still connected through the transformers and run a test on it. I prefer the old fashion way but some guys love the EZ Restore. One thing we do for safety since we are out there by ourselves - once I find a blown fuse, that door is coming with me while I run targets and I will give the operator a call to let him know my where abouts. We are supposed to hang a tag on the cut-out w/ our phone number in case a second man responds to the same call. Something else to think about - I have found that alot of times, check your map recors of your urd cable layout and find your longest run of cable. Alot of times that is your faulted section, and it saves you from running all over. Another thing too remember is that if you are running trouble on a 3 phase loop with 3 phase transformers, even if the cables have fault indicators on them... alot of times they will reset themselves from induced voltage or backfeed on 3 phase applications. Stay safe!!

reppy007
02-16-2012, 02:22 PM
Here at the company I work for that is a 1 man operation. We have fault indicators in pretty much every pad mount transformer so that makes it a bit easier. Once I find the blown fuse, and no wildlife at the base of the pole, I will check the first pot for a target. If I have a target there and it is a long loop, I will split the loop half way and try the fuse one time. that will at least let me know weather the fault is in the first half or second half of the loop and I can get part service back. We have a cable reel tester that we use but it can be quitre time consuming as the cable has to be isolated between both pots to test it. We also have another cable tester thats called the EZ Restore. You can use that while the cables are still connected through the transformers and run a test on it. I prefer the old fashion way but some guys love the EZ Restore. One thing we do for safety since we are out there by ourselves - once I find a blown fuse, that door is coming with me while I run targets and I will give the operator a call to let him know my where abouts. We are supposed to hang a tag on the cut-out w/ our phone number in case a second man responds to the same call. Something else to think about - I have found that alot of times, check your map recors of your urd cable layout and find your longest run of cable. Alot of times that is your faulted section, and it saves you from running all over. Another thing too remember is that if you are running trouble on a 3 phase loop with 3 phase transformers, even if the cables have fault indicators on them... alot of times they will reset themselves from induced voltage or backfeed on 3 phase applications. Stay safe!!

The old fashioned way works....can at times be time consuming........but if the cable is old,and there is a insert bushing not installed correctly........or a probe that isnt tightened correctly ....the fault current may create another fault other than the one you are trying to locate................Id learn the Ez Restore........and use it,even if it taked a little extra time......Id bet your getting paid by the hour............some stuff I didnt like .......but sometimes you have to suck it up and change with the times.:D

Liledgy
02-16-2012, 08:51 PM
Here at the company I work for that is a 1 man operation. We have fault indicators in pretty much every pad mount transformer so that makes it a bit easier. Once I find the blown fuse, and no wildlife at the base of the pole, I will check the first pot for a target. If I have a target there and it is a long loop, I will split the loop half way and try the fuse one time. that will at least let me know weather the fault is in the first half or second half of the loop and I can get part service back. We have a cable reel tester that we use but it can be quitre time consuming as the cable has to be isolated between both pots to test it. We also have another cable tester thats called the EZ Restore. You can use that while the cables are still connected through the transformers and run a test on it. I prefer the old fashion way but some guys love the EZ Restore. One thing we do for safety since we are out there by ourselves - once I find a blown fuse, that door is coming with me while I run targets and I will give the operator a call to let him know my where abouts. We are supposed to hang a tag on the cut-out w/ our phone number in case a second man responds to the same call. Something else to think about - I have found that alot of times, check your map recors of your urd cable layout and find your longest run of cable. Alot of times that is your faulted section, and it saves you from running all over. Another thing too remember is that if you are running trouble on a 3 phase loop with 3 phase transformers, even if the cables have fault indicators on them... alot of times they will reset themselves from induced voltage or backfeed on 3 phase applications. Stay safe!!
Prior military, you said you split it in half and try the fuse if the first indicator is tripped. What did the indicator read at the middle? If it was tripped, why not keep going, say, 3/4 of the way, or the next long run and check a target? Well at least your working on a system that spent their money wisely and installed fi's.

Pootnaigle
02-16-2012, 08:58 PM
Ummmmmmm we had FIs on all of our stuff even the laterals.It would be an all nighter to find a fault on most of our stuff otherwise. I really liked the ones that strobed . didnt even hafta open the cabinet.

rob8210
02-16-2012, 09:05 PM
The underground system I learned on had for the most part, fault indicators on the -2 side of each transformer. Now some of the older areas didn't so we got to learn a few different ways of troubleshooting underground.

mr1234uo
07-21-2012, 01:18 PM
use a grass hopper fault indicator very reliable. the close your cut out with a current limiter

birdog37
07-22-2012, 03:11 PM
Checking the fault indicators can be very useful tool.I would definitely utilize these if there out there.Also check area for a dig in is good,but as far as closing a fuse on a fault your subjecting your cable to more stress of fault current.At least check the map and if you have old cable isolate that section.Get the new back on.Call for the fault wizard.This machine is state of the art,very user friendly to a lineman.It will actually tell you how far out the fault is,get close ,isolate and then start your leap frogging using your capacitor sticks to find the bad cable.Isolate the cable by putting them on stand offs. Get everybody on you can.Now your ready to thump the cable with the same machine.Especially if its a radial,your going to have to dig it up so call for your emergency locates ASAP.No need for head phones this machine does it all.Fault wizard is a great lineman's tool.

reppy007
07-26-2012, 10:31 AM
Checking the fault indicators can be very useful tool.I would definitely utilize these if there out there.Also check area for a dig in is good,but as far as closing a fuse on a fault your subjecting your cable to more stress of fault current.At least check the map and if you have old cable isolate that section.Get the new back on.Call for the fault wizard.This machine is state of the art,very user friendly to a lineman.It will actually tell you how far out the fault is,get close ,isolate and then start your leap frogging using your capacitor sticks to find the bad cable.Isolate the cable by putting them on stand offs. Get everybody on you can.Now your ready to thump the cable with the same machine.Especially if its a radial,your going to have to dig it up so call for your emergency locates ASAP.No need for head phones this machine does it all.Fault wizard is a great lineman's tool.

there are several types of urd locating equipment out there,I used 3 types,my favorite was a german made machine,measured in meters...the biggest problem Ive seen with any of the vans,ect was the operators,some really werent good with underground,some didnt really know how to operate the equipment well,but they made management think they knew what they were doing,saying that,there were some others that were lots of help when you worked with them,very sharp guys out there.

birdog37
07-26-2012, 10:04 PM
As I said,this fault wizard is great.It is portable,user friendly.Keep the battery charged and ya carry it to where ever ya need to trouble shoot.With any luck its not from the dip to your 1st tub,then ya can thump a shot threw your xformers,get a distance roughly estimated within a distance of say 20 ft.Isolate to there, and then you can put it on a mode to get a good burn,then start your thumping process.This gives a thump about every 6 seconds.This is so the machine has enough time to build a charge,then it sends it.you can get right on top of it quickly to find the fault.Hope ya called in for your emergency locate so you can getter done. I'm sure there's a link out there somewhere on this time saving device and equipment saving device.

reppy007
07-27-2012, 03:40 PM
As I said,this fault wizard is great.It is portable,user friendly.Keep the battery charged and ya carry it to where ever ya need to trouble shoot.With any luck its not from the dip to your 1st tub,then ya can thump a shot threw your xformers,get a distance roughly estimated within a distance of say 20 ft.Isolate to there, and then you can put it on a mode to get a good burn,then start your thumping process.This gives a thump about every 10 seconds.This is so the machine has enough time to build a charge,then it sends it.you can get right on top of it quickly to find the fault.Hope ya called in for your emergency locate so you can getter done. I'm sure there's a link out there somewhere on this time saving device and equipment saving device.

we have heard of them.....so does yours have any type of screen where you can see the fault or is it just a thumper?

birdog37
07-27-2012, 07:45 PM
The info it gives is the distance to the fault in ft. and what voltage your raising it to.You can actually watch it build before it discharges while your thumping or when your in the burn mode.You may want to consider lowering the burn if your dealing with a 3 phase situation thou so you don't damage the other conductors in the same trench.

reppy007
07-27-2012, 09:33 PM
The info it gives is the distance to the fault in ft. and what voltage your raising it to.You can actually watch it build before it discharges while your thumping or when your in the burn mode.You may want to consider lowering the burn if your dealing with a 3 phase situation thou so you don't damage the other conductors in the same trench.

Cool ,as long as it gives you the distance,thats helps out alot,as you know you wont always be able to hear it thumping in the ground,for example if there is a pull hole/pull box and its full of water,usually you wont hear the thump,or if the original fault blew the concentric in the clear and the wire is in pipe,that too can be hard to find by thumping....and finally if the fault is near a busy intersection/freeway it might be impossible to hear a thump.Ive seen a few that had screens that you could actully see the wire,and the opening or a ground,that caused the outage in the first place.Anything beats the old way.

birdog37
07-28-2012, 07:52 PM
More great info. THX.

flashman
07-31-2012, 07:43 PM
Closing into suspected faults is a really bad practice. It damages the wires further and creates more work in the long run. We got away from that practice both for safety reasons and destruction of equipment.

UGL
09-04-2012, 06:44 PM
where I work we usually have fault indicators in our pad mounted equipment, and we run 1 man trucks. which sucks when you have more then two trans on a run. first we'll run down the targets if we get a section with that then we test it with a test box. if targets don't help clear up the trans put elbow is feed thru's go to the middle test both ways and slowly start sectionalizing. some guys will still try the fuse as their first step. I never thought it was good to close in on an unknown.

flashman
01-28-2013, 11:51 AM
I have done trouble calls in undeground circuits for too many years. I have see just about everything that could go wrong go wrong with underground circuits. Unfortunately it comes down to money once again. Safety should be paramount in our work as troublemen but to some companies and some cowboys out there it's full speed ahead at any cost to save a buck or earn one. OHSA states when working on energized conductors (energized is consider not grounded) within the safe work clearance two men should be utilized both of same grade to work on or near said voltage. I know the cowboys and companies have seen it all and done it all. The one thing they probablly haven't done is go down to the burn unit at a local hospital and see the people who have had accidents. Banging fuses into an underground wire that is faulte further weakens the entire wire. Test the wire for faults BEFORE you install a blown fuse if possible is the best way to do it. I don't expect your company or some of the cowboys out there will believe this.

mr1234uo
02-23-2013, 09:37 AM
we install grass hopper fault indicators then we close the cutout with a current limitor.