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Electriceel
06-06-2011, 11:24 PM
We seem to be having more than our share of fuses pulling apart.
I was taught that any fuse less than 25 amps to wrap it counterclockwise to avoid stretching it.
Seems that since I learned from the school of hard knocks, that the college idiots never were told this from their instructors so they are assuming that their instructors (whom a lot of them failed as lineman) are right.
Any other ideas?

Pootnaigle
06-06-2011, 11:45 PM
Are you sure they are falling apart or could they be melting?The actual fuselink is located near the button and an examination mite just show evidence of heat.
As far as what direction to wrap one I always wrapped them clockwise so that as the tension nut was tightened the fuse tail didnt try and backoff.

T-Man
06-07-2011, 05:53 AM
Wrap clockwise,(all wire under a nut should be wrapped clockwise unless you have a reverse threaded stud) and just enough tension on the link to hold the spring loaded flapper in place so the door or Throttle will stay closed. When the fuse let's go the flapper releases and the door drops. Sometimes the steel tail of the fuse link will corrode and break right at the flapper, all the rest of the time they melt on overlaod or blow on a fault to ground.
Added info: always refuse with the proper size to keep the co-ordination correct up the line. Your application engineers should know how they want that line fused along with the reclosers and breakers.

loodvig
06-07-2011, 06:42 AM
I've always done it clockwise. AND not too tight. But I have found some where the tail of the fuse was just under the nut and not under the washer! So when the nut was tightened it pulled on the tail.

MI-Lineman
06-07-2011, 06:59 PM
Never heard that.

Always went Clockwise on all fuses. Tightened em as much as ya could with your fingers, then just a "cinch" a bit with your channelocks.

Maby a real Lineman can tell ya better.:D

What's that supposed to mean?:rolleyes: If you're sick of the BS from some of the "real Lineman" then stop tryin to start a feud again? "Lead by example" remember?;) Don't blow your cool now!!!

Anyways, I never seen'em pull apart either and not too snug and tighten clockwise. Maybe you all got a bad batch if it's happening all of a sudden?

6/8

topgroove
06-07-2011, 07:56 PM
I've refused thousands of times and have never seen a fuse link pull apart. Try it yourself... stick it in the vice and try and pull it apart with your slack blocks. I suppose if your determined you could pull it apart, but its not gonna come apart all by itself in the fuse holder. I have seen lightning strikes where the fuse link looked like it was cut clean. and Always always wrap it clockwise:)

MI-Lineman
06-08-2011, 05:22 PM
I thought I always said "A real lineman should know and understand theory" and you disagreed? I never meant to say you weren't "a real Lineman" just cause you don't?:D Well I think I did once when we was feudin but I believed I apologized? Never gonna let it go are you?:rolleyes::D

I say I'm right with the bad batch?

Pootnaigle
06-08-2011, 05:41 PM
If they are actually breakin I spoze I wud hafta side with MI. Never personally seen it myself.But Swamp was correct also it needs to be wrapped clockwise regardless of fuse size.I have heard that if that tail isnt tightened properly( IE too lose or too tight) that it wont work properly. I dont know if thats true or not. I sure as hell never used a torque wrench on one.

T-Man
06-08-2011, 06:11 PM
Poot, I don't think it matters how tight but may matter how loose. In the days just before me, the fuse cutout was a spring on top and a spring on the bottom. You had a fuse with two rings one at each end, You would hook one end in the bottom spring and the other with a switch stick in the top spring, picking up load or fault like that. . . I look around and see if I can find a picture of one of those or I'll visit the training center and get a pic that way.

Pootnaigle
06-08-2011, 06:30 PM
Ummmmmmmm we called them bad boys butterfly fuses n I hated em. No door involved just the fuse link hung tween top n bottom under tension

T-Man
06-09-2011, 03:14 PM
Heh, heh, heh....
I know Mike....just pullin your chain man.:D I never took it to heart. Not a hell of alot gets to me. And yes you did appoligize.

I wish I could remember who posted it,.... but one Lineman on here said there was ENTIRELY too much math education and theory in todays apprenticeships. THAT I agree with. Teach Basic theory...They're gonna be LINEMEN for gods sake! Teach em how to read PRINTS!!:D All Linemen know...ENGINEERS are the GODS! We just the Mules.:rolleyes:



We use to call em "Grasshoppers"....miserable things. Especially at night on a trouble call.:mad: The ones with the rings on both ends, right?

You got the picture. I never had to refuse one of those in the field, but I can see they would be pretty crumby in the dark and rain and then if there was a fault a good flash to blind ya for a while at the least.

Most likely you found them on 2200, 2400 or maybe 4800 so the load vs voltage could be a pretty good arc. I'd rather slap on a Hot Line Tap than make up one of those.

Pootnaigle
06-09-2011, 03:29 PM
Ummmmmmm I stand corrected you are absolutely right they wuz Grasshoppers, and miserble thangs at that.I've done em wif a shotgun but I aint even sure itz possible with a long stick.

T-Man
06-09-2011, 05:43 PM
Back in the day I had a switch stick that was 4 feet long. I could hook it on my belt and not have it get in the way, then use it for closing cutouts and opening and closing switches. This was of course before all the rules changed and I had to get rid of my stick and copper hook and all the other stuff deemed unsafe.

From the ground you'd be a super lineman if you could install a fuse in a grasshopper in my opinion. I did know a guy that could install a door and close a fuse box with an extendo stick all the while dressed in a lime green leasure suit, bell bottoms and all. He came to work each day dressed like one of the Bee Gees. . .

Pootnaigle
06-09-2011, 06:12 PM
Ummmm yeah I hadda lil 8ft extendo for the bucket truck. Handiest tool ever. Naturally outlawed for opening or closing anything, But I kept mine hid and when It got found I told em I used it with a saw attachment.( I maybe fibbed)
As far as those old box style Explosion proof cutouts I hated them damn thangs with a passion. I bleve in my hole career I managed to refuse 2 of em from the ground.More often than not the eye was broken off of the door. Bleve it or not those thangs are still being sold and used in some non utility applications. It wouldda been nice to have welding goggles for grasshopper fuses. cause it was damn sure hit n miss a bunch.

Koga
06-09-2011, 09:15 PM
add , be sure and give the top of the cut out barrel a twist with the pliers. A tiny little slack in the the fuse cord , plus a top of the barrel not tight and ya got yourself a problem down the road.


Koga

wtdoor67
06-09-2011, 09:18 PM
You can put them in with an extendo. Did it plenty. Not as hard as removing or installing a hotclamp with an extendo.

I had seen grasshopper cutouts some and thought they were obsolete. Got to wide and wonderful Wyoming and they still gottem new in the box. I think they were Kearneys, and I remember they were 50 amp cutouts. Although the system had plenty on 3 phase installations we only used them for single phase transformers. 7200 and below.

Tripolinks I think they were actually called. Didn't like putting them into a fault at night as you had to look at the damn things to close them.

One thing though. If you didn't have the proper size fuse, you could just add increments until you had enough amps. If you needed a 40 you could put in two 20's. Just one on each side. Or you could just stack them, one on top of another.

Should have collected some of that stuff.

MI-Lineman
06-09-2011, 09:28 PM
They still use'm at a muni (TriCounty) here!

wtdoor67
06-10-2011, 10:27 AM
They still use'm at a muni (TriCounty) here!

Cheap, you know. Everyone is supposed to wear safety glasses anyway.

duckhunter
06-10-2011, 08:00 PM
I think sometimes fuses get weak from minimal blast of overcurrent, like lightning, and just let loose in an high load situation. You get lot's of calls where the member says they heard a bang and these ones nothing.

I agree with the lightning that burns one clean too.

PSE Lineman
06-13-2011, 09:57 PM
The fuses for "grasshoppers" are called trip-o-link fuses direct from the box. You don't have to look at them when you refuse. I use a 12 ft stick, one solid and one extendo that rides in my bucket with me at all times in a scabbard with a water tight lid. Which ever I use, I get it close, duck my eyes under the brim and swat at it. If it's gonna blow, it'll do it then. Also, if it starts percolatin', you just have to let go and not have to try to get it open in a hurry. When you figure out it's going to hold, then you can put it in to stay by just letting it rest on it's little keeper, not tug it into the top fork. That way you , or the next guy can get it out easy for another new fuse. I also have been able to put them in from the ground with the big extendo when you can't get to the pole with a bucket. Done 'em in the dark with a flashlight too, with a little help from the customer holding it. As for the fuse wrap, I stated to wrap 6, 10 and 15 amp fuses counter clockwise so they won't tighten tighter with the nut with the built in washer. The nut and washer are one unit and over tightens the fuse when you turn it ever so slightly. You just have to hold the tail tighter with your thumb. The spring has enough tension to have a little slack for fuse breakage. Too many times I have refused a 6T with only a few amps on them with no reason for coming apart. Our cutouts (not grasshoppers) are chance, the ones that split down the middle or burns up on the stud where it hangs with the arm to break the fuse to open under load without a load buster. No, they aren't changing the cutouts out, went over that a few years ago. We still find them, collect the date on it and call the engineer and then toss it. They seem to be 95, 96 and 97's. DAMN, i'm getting off topic!!! Wait, we're talkin about fuses that are used by cutouts so I guess i'm OK!!....maybe....

Divemaster
06-14-2011, 11:44 PM
Twenty years ago when I got into this trade, my foreman took me out to turn on irrigation wells that at that time most of em had grsasshoppers. He would do the cutouts and he patiently had me do the gradsshoppers with an extendo even though my arms were becoming numb. To me, thats the best way to learn how to use an extendo from the ground. Makes operating cutouts, switches and OCRs alot easier and it gives you confidence in your ability in using an extendo when you have to. If you are proficient, it's faster than having to gear up to climb a pole. I do have to admit though, I will never be as good as Tony is.

tramp67
06-16-2011, 10:01 PM
Going back to the beginning of this thread, in some climates with big temperature changes between summer and winter, Midwest especially, we would occasionally run across what we called "cold pulls". If the fuse link was pulled tight with no play in the flipper of the cutout door in the summer, sometimes the fuse would contract enough to "pull" apart in cold weather. A lot of tension from the metal contracting in the winter, the barrel is pretty dimensionally stable with temperature changes. We would leave a 1/4 inch or so of play in the flipper when tightening the fuse lead under the nut in a clockwise wrap. This doesn't affect the operation of the cutout at all.
Leaving cutout doors hanging upside down for long periods can cause the fuse link to deteriorate over time from the water that accumulates in the barrel. If a cutout is to be left open for a long time, remove the barrel and staple it to the pole or hang it by the ring on the bottom of the cutout to keep water out of the barrel.

Highplains Drifter
06-16-2011, 10:14 PM
Going back to the beginning of this thread, in some climates with big temperature changes between summer and winter, Midwest especially, we would occasionally run across what we called "cold pulls". If the fuse link was pulled tight with no play in the flipper of the cutout door in the summer, sometimes the fuse would contract enough to "pull" apart in cold weather. A lot of tension from the metal contracting in the winter, the barrel is pretty dimensionally stable with temperature changes. We would leave a 1/4 inch or so of play in the flipper when tightening the fuse lead under the nut in a clockwise wrap. This doesn't affect the operation of the cutout at all.
Leaving cutout doors hanging upside down for long periods can cause the fuse link to deteriorate over time from the water that accumulates in the barrel. If a cutout is to be left open for a long time, remove the barrel and staple it to the pole or hang it by the ring on the bottom of the cutout to keep water out of the barrel.


A pole step makes a perfect hanger....

wtdoor67
06-16-2011, 10:32 PM
I also have been able to put them in from the ground with the big extendo when you can't get to the pole with a bucket. Mercy!


I've seen hail storms knock out those tripolinks.

reppy007
11-02-2011, 03:39 PM
Excuse me,ive heard it all,ive even seen the so-called pulled fuses.A while back whenever we found a fuse that seemed to melt out ,our policy was to amp it,so to get around the amping portion,the pulled fuse term came along.I used to think to myself who the **** is pulling all these fuses.Maybe the intentional weak part of the fuse were too sensitive?But heres what i really want too say,many moons ago as i was a helper,me and an apprentice refused a linefuse,after a large thunderstorm.I refused it and he hung it and closed it.Apparently the lights came on,later on we,being the big crew got that same call.Well we notice that the barrel is still in,but there is no lights,we even looked for a broken jumper on this 3 phase lateral,nothing found.Well that kind of threw us for a loop until i spoke up and asked them to open the fuse and take a look at it.So we did that,and ill be a mother-ucker if there was no fuse in the barrel,so the four of us kind of scratched our heads ,wondering how that could happen.A 12 kv kerney barrel closed in,with-out a fuse?Still to this day i dont know what happened.Twenty years after that happened,that same apprentice was working for me with the contractors,while we ate lunch at this bar-b que joint, i asked him if he remembered that day,and he looks at me crazy and tells me that he did.Iwas beganing to think that maybe it didnt happen,but he confirmed that it did.Ill never really know what happened ,but way back in my mind tells me that this clever troubleshooter might have doubled back and rigged the barrel someway,you all know how lineman come up with some dirty tricks,all i have to say is that was a good one,no blown barrel cap,no f-cking fuse,damn.

AEPline
12-18-2011, 01:50 PM
we had some fuses ( 4x to 8t) pulling apart on newer doors that had a double spring. Those doors were supposed to only be used on capacitor settings. That is what was told anyway. No other problems that i heard of as far as the bigger size fuses go.
I (we) use extendos for everything. On another topic---the chance cutouts from 92-97 I beleive are the real bad ones. They have a stainless steel hood on the top--- we call them shiny tops. Still come across on every now and then.