Found this secondary burned in half

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brantmacga

brantmacga

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Georgia
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Pulled this out Friday; 500kcm AL secondary underground. This is one of a parallel set. The building has been closed awhile and the owner just leased it out. When poco came to energize, found that one of the A phase conductors had been cut in CT cabinet, and said the other A phase had no voltage.

This is what I pulled out on set with no voltage. The other 100' half is still in the ground. Headed back tomorrow to make another attempt at getting it out and seeing if the conduit is good.




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C

Cow

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Eastern Oregon
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Corroded in half. We see that on a regular basis with all the DB aluminum feeding irrigation pivots in this area.
 
brantmacga

brantmacga

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Yeah... That's a more accurate statement. I feel like it must have been cut on install. I think this building is less than 5/yrs old.


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kwired

kwired

Electron manager
Location
NE Nebraska
Careless handling before or during installation can cause those troubles. Aluminum underground doesn't take long to oxidize until there is no longer a complete circuit if insulation is damaged enough to expose the conductor. Given the right conditions it can become an open circuit in just a few weeks. White powdery stuff you find where the conductor is supposed to be is aluminum oxide.

Out in the desert may take longer to fail. Buried in high water table location or other situations where raceway fills with water easily it don't take long at all for failure, just a pin hole in insulation will get it started.
 
kwired

kwired

Electron manager
Location
NE Nebraska
Your image hadn't showed up for me before last post, but did appear after my reply. I'd say the one conductor as long as the damaged spot is probably had a long rip or tear in the insulation during installation. Other adjacent conductors sometimes suffer heat damage from faulting conditions and that deteriorates their insulation enough they are able to start to oxidize. The fact that one has the longer damage area sure makes one wonder if that is what maybe happened.

Before the first conductor completely failed the cross sectional area had to diminish, eventually down to very little area, which very likely left that section of conductor glowing, depending on load characteristics for a certain period before it completely opened.
 
brantmacga

brantmacga

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Location
Georgia
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Former Child
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So this spool marks where it's broken; conduit is running left to right underground in this photo.

Notice anything suspicious?


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brantmacga

brantmacga

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Georgia
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Former Child
mgookin said:
It took me a minute to find the 2nd inlet directly behind your spool.
Your bill is the same though, right?
Click to expand...

Haha.... They wish.

Just had to call in a locate so we can saw up the asphalt and start digging.

Couldn't get the other half of the wire out.


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brantmacga

brantmacga

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Georgia
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It was close ..... I thought the storm drain had got it, but once I ran the locator, got an accurate measurement and dug it up, I was able to confirm it was the pole base .


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brantmacga

brantmacga

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Location
Georgia
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Former Child
I also found they missed the gas line by 1".... Not sure if they were aware or not, but seeing as how they bored their own secondary, I'm guessing it was luck.


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