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canyonman
05-05-2005, 11:52 AM
Has anybody come across the problem of , the fuse blowing but he door not opening and tracking across the door leaving the pots or padmounts hot.

thrasher
05-05-2005, 03:56 PM
Have seen this several times usually with old fuse tubes that the fiberglass is beginning to "feather". The feathering seems to trap dust and moisture and provide a path for current. Most were either Southern States or McGraw-Edison cutouts.

LINETRASH
05-05-2005, 05:22 PM
yep. I see it quite often.

usually its also smoking.

i've seen them cary a transformer. The phase tracks on the contaminated barrel.

If I get one on a loop, that puppy is smokin!

Down here it is almost always a chance cutout.

In fact, I have developed the habit of closely looking at the cutout when I get to a trouble call, looking for the tail of the blown fuse. This is because of the frequency of these devices failure to drop.

Tsplice
05-05-2005, 09:13 PM
I just had one a few months ago that took out the main feeder back to the PMH gear, blowing an 80 amp fuse!The fuse had blown sometime ago,do to a faulted cable,door failed to open,and the rest is history.

Tsplice

KyLineman
05-05-2005, 10:14 PM
We have several Kearney cutouts that will do that, fuse blows or just breaks and the door will not open. It will track across sometimes smoking then catching on fire. And burning into. Love those kearney cutouts, easy OT.

lightningrod
05-05-2005, 10:29 PM
We have several Kearney cutouts that will do that, fuse blows or just breaks and the door will not open. It will track across sometimes smoking then catching on fire. And burning into. Love those kearney cutouts, easy OT.

Had them burn the doors off many times, also the chance load breaks fail to open over half the time.

markwho
05-05-2005, 10:56 PM
I have not had this happen to me personally, but my co-workers have had some experiences with it. It always comes to mind when I troubleshoot, so I usually take the time to open the cutout before performing any work down the line.

pike rat
05-06-2005, 12:50 AM
This happend a lot on fpc sys they got a bad run of doors a few years back

Boguerat
05-06-2005, 08:12 AM
Here in Illinois we come across that alot. Usually it the older fiberglass door cutouts. Had a trouble call a couple of years ago, people called in saying they heard a load bang and lights went out, pulled up the the house and the lights were on. I asked the couple what happened, and said, lights came on afew minutes after they called. Went around back to look and the door was closed,(25 kva Two Homes On It) it was blown but still working, had to lift the tap, couldn't pull it open.

Lately we have had alot of Chance cutout burning up arms and pulls because of cracks in the glass. we are getting on average 2 a week, the weather here has been great no storms yet ( no extra money ) company is looking into it.

I make it a habit of not using an extendo stick when ever possible, I want to look at the cutout a little closer. Had a bad one about 6 years ago changing out arrestors on rearlot tranformers. Climb up to open and didn't see the crack, cutout broke in half, luckly the top half got hung up on the 8' stick and I could hold it from falling onto the transformer, crewleader always said he could thread a needle with an extendo stick, he had to lift the tap from the ground while I sat up there with my a@#hole puckered and balls sucked in.

thrasher
05-06-2005, 08:58 AM
Hey Man, I hope I just misunderstood something on your earlier post. But it sounds like you don't routinely get a visible opening to do trouble work on the line. Does this mean you usually do all your trouble work in gloves treating the line as hot or did I just take the comment wrong?

markwho
05-08-2005, 12:00 PM
Thrasher, If I spot a blown fuse with the door still closed I take the time to open the door before proceeding to work on the line if it is protecting a lateral. Either way it is worked with gloves and sleeves and treated as energized unless it is tested dead and grounded.

Markwho

lightningrod
05-11-2005, 10:00 PM
[QUOTE=Boguerat]Lately we have had alot of Chance cutout burning up arms and poles because of cracks in the glass. we are getting on average 2 a week, the weather here has been great no storms yet ( no extra money ) company is looking into it.

Those cutouts by chance have been failing at every utility that is using them, we have had as many as 7 poles burn off in one day due to them. The grout that holds the metal parts to the porcelin "grows" causing the cracks, moisture invades and causing tracking and then the fires. We have changed out over 4000 of them so far to synthetic cutouts in a program and the pole fires have been greatly reduced.

But a pole is the last thing on my mind to save, I just think that by getting rid of these death traps we may save a lineman's life.

loodvig
05-13-2005, 06:44 AM
We also have had 100's of AB Chance cutouts tracking/burning! I had 2 yesterday! The 15 kv, 100 amp load break type.

Boguerat
05-14-2005, 09:10 AM
Thanks for that info Lightingrod. Trying to get any info from our company on problems we encounter, or problems we see, (because we know how to do linework) is hard. The suits don't want to hear that there is problems with the system. I feel that in afew years we will be going to some type of program like yours and change out these cutouts to different types.

Has anyone out there ever heard anything from Chance about this problem?

Kingpin
05-15-2005, 12:26 PM
I have seen the doors fail to drop numerous times due to age, dirt, deterioration etc...I always carry extra doors in the truck and change out older doors as you refuse if you feel it is needed.

Roger Larkin
08-24-2006, 09:17 AM
I recentlly acquired some test reports on cut-outs and yes the manufactureres are aware of the problem. The reports are fairlly technical but they are interesting to read. If interested,send me a PM and I will attach 3 PDF files for you. Not quite sure if they can attach to this post

flashman
09-03-2006, 03:04 PM
Good afternoon all, I was sent to a trouble call about a fire on the pole awhile back. When I got there the fireman pointed to the fused cutout it was a little black and the fuse was blown but the funny thing was that there was no outage. The darn thing was still feeding a 50kw transformer and the lights were just as bright as normal. I always open the fuse when working and even take off the riser for sure. Flashman

tramp67
09-04-2006, 01:06 AM
I've run across "one shot charlies" also that the fuse blew and the fiber barrel continued to conduct until the entire barrel burns up. Sometimes the insects like to nest in cutout barrels and after the fuse blows, the carbon from the burnt bugs conducts, with everything being packed so tight the end of the fuse lead can't drop out of the barrel.

Stinger
09-10-2006, 09:30 AM
Tramp, I've run into that a lot. Specially storm work. Pull up to pole, the ape will say the door is not open, whats the problem? Thats when you go into your classroom modeand begin to tell the ape excatly what you related. After that you watch the ape pull the door and start trying to clean out the barrel. Thats when you tell the ape, no son, just put up a new cut out becasue you can no longer determine the integrity of the old door if it has been buring inside.

loodvig
09-11-2006, 06:45 AM
I had one this last weekend on the new Hubble polymer cutout. It burnt clear while I was setting up the truck. The customer said his lights were flickering but never went out. We are near the ocean so it may have been the salt build up! Tracking on the barrel.

igloo64
09-20-2006, 11:54 PM
Dont forget AB chance , fargo ,and whatever other companies were bought out by hubble and most of their equiptment is made in China. Seems quality is not as important as quantity1 :(

Damn Yankee
09-22-2006, 11:25 AM
Chance inports porcelain cutouts from Mexico

loadbreak55
09-23-2006, 10:12 AM
:p We 've had lot's of these over the years.Hell,once I responded to an outage call,went to my first point of isolation,an 85 "t" fuse.Not only did the fuse blow,but there was nothing left of the door!not even the hinge!All gone.But that's not what I'm here to talk about today.I'm curious;have any of you guy's ever had a PMH fuse blow,and the target fail to "pop-up"?Until a few month's ago,I never had this happen,and since,it's happened two more times!Not in the same PMH gear,just various ones.The common factor is they are all S&C's. :confused:

doug
09-23-2006, 11:11 PM
I Have To Agree About Most Of The Line Materials Being Made In
Mexico-china-brazil-etc.profits Over Everything Else????.

Also I Have Been Told That All Cutout Doors Have A Extinguishing
Stuff Inside The Doors To Help Put Out The Arc-flash And That
It Wears Out Over Time With Each Fuse Blowning???

I Have Had Door In Past That Could Carry Enough Volts To Run Lights In A House But Not A Heavy Load.just Because The Fuse Tail
Is Hanging Out The End Of Door Doesn't Mean That Your Safe!!!!!!!
Always Protect Yourself!!!!!

Be Safe

thrasher
09-25-2006, 07:34 AM
In most style fuses the extingushing chemical is contained in the cardboard sleeve over the center of the fuse link not in the tube itself.

Damn Yankee
09-25-2006, 09:26 AM
Also I Have Been Told That All Cutout Doors Have A Extinguishing
Stuff Inside The Doors To Help Put Out The Arc-flash And That
It Wears Out Over Time With Each Fuse Blowning???


Always Protect Yourself!!!!!

Be Safe

The fuse tube/holder, or "door", contains either a horn fiber (bone fiber) inner liner, or a synthetic liner to aid in extingushing the arc. The interaction of the arc with the liner creates a gas, which pressurizes the fuse holder and in turn vents through the bottom end of the tube. This process expells the hot gasses and fuse link parts sacrifised during the interruption. Both liner types are usually only good for three interruptions at rated voltage and current, so yes, it is good practice to inspect the fuse holder while refusing.

Another thing to point out, the horn, or bone fiber materials absorb moisture and swell, decreasing the inside diamter of the fuse tube, sometimes to the point of restricting the flow of gas, and exit of the fuse link.