Conductor strands missing!

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DrHolehawg

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Boulder Creek, California USA
Hello to all, just recently i discovered my 4/0 service entrance conductors had 9 out of 19 strands cut and were not under the terminal. The other leg was much "better" and only had 4 missing!
What issues would this contribute to in a typical residential application besides the obvious risks at the connection itself. Is there any possibility it could contribute to wacky meter performance ?
 
If you start drawing serious current, that connection will over heat. and it sounds like it is not fuse protected, so you may want to correct it.
 
For my own house, I probably would not worry about a couple missing but would fix it for a customer because it is the right thing to do.

I would certainly be concerned about almost 1/2 of the strands missing in my home and would fix it. Reasons as stated by the others.
 
the blur said:
If you start drawing serious current, that connection will over heat. and it sounds like it is not fuse protected, so you may want to correct it.
Click to expand...

A fuse will not know the difference, it will only respond to the current actually drawn.

I see bad terminations burn up all the time that never cause a fuse or breaker to open, both line side connections and load side connections. Load side of fuses do seem to have more of a chance to open the fuse because they are in closer proximity to the connection (no disconnect mechanism on the load side) and heat from the poor termination migrates into the fuse faster than it would if it has to migrate through the disconnect.
 
I don't make up the rules

I don't make up the rules

I don't make up the rules, I just follow them. Wire is damaged at the termination points you can see. It goes to reason the wire may be damaged at the other end of the wire you can't see. Might even be cross wired in the meter but probably loose or damaged in some way.

Being in the business of electrical contracting I would make an offer to fix it. Might even make some money at it.:angel:
 
I assuming it is 200Amp residential service. You can replace with 2/0 copper service conductors.
I am almost 100% sure that 2/0 is fine in your neck of the woods. But check with the AHJ first.
 
DrHolehawg said:
Hello to all, just recently i discovered my 4/0 service entrance conductors had 9 out of 19 strands cut and were not under the terminal. The other leg was much "better" and only had 4 missing!
What issues would this contribute to in a typical residential application besides the obvious risks at the connection itself. Is there any possibility it could contribute to wacky meter performance ?
Click to expand...

What do you mean by wacky meter performance? What symptoms are being experienced?
 
May be the strands were intentionally cut to suit . (over cut where nine strands were missing !). Suitable cable lugs at the terminals may solve the issue.
 
DrHolehawg said:
Hello to all, just recently i discovered my 4/0 service entrance conductors had 9 out of 19 strands cut and were not under the terminal. The other leg was much "better" and only had 4 missing!
What issues would this contribute to in a typical residential application besides the obvious risks at the connection itself. Is there any possibility it could contribute to wacky meter performance ?
Click to expand...

I am soomewhat surprised by the general response. IMNSHO when you have half the strands missing the current rating of that cable is reduced by half. If your feeder protection is sized for a 4/0 cable then the missing strands would result in inproper protection of the feeder. (I don't know how could you legally size 'reduced' protection since the only size you can take into consdieration is the one that is printed on the conductor jacket, you can't just 'determine' that the missing half strands result in a, say, 2/0 cable.)
 
weressl said:
I am soomewhat surprised by the general response. IMNSHO when you have half the strands missing the current rating of that cable is reduced by half. If your feeder protection is sized for a 4/0 cable then the missing strands would result in inproper protection of the feeder. (I don't know how could you legally size 'reduced' protection since the only size you can take into consdieration is the one that is printed on the conductor jacket, you can't just 'determine' that the missing half strands result in a, say, 2/0 cable.)
Click to expand...

Total area of 4/0 is 211600 circular mills. Half of that is just a little more than the area of 1/0. ;)

There is probably an odd number of strands, 19 is typical, so you can not have half of them gone without splitting one strand:lol:
 
weressl said:
I am soomewhat surprised by the general response. IMNSHO when you have half the strands missing the current rating of that cable is reduced by half. If your feeder protection is sized for a 4/0 cable then the missing strands would result in inproper protection of the feeder. (I don't know how could you legally size 'reduced' protection since the only size you can take into consdieration is the one that is printed on the conductor jacket, you can't just 'determine' that the missing half strands result in a, say, 2/0 cable.)
Click to expand...

I was under the impression the OP knew that it was wrong to cut strands and knew of the risk of overheating and fire, but wanted to know if there were other problems that might have occurred due to the cut strands.
 
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