Is this a POCO problem?

[scottam99]

A friend of mine is doing some remodeling on an existin house. When he uses his chop saw it doesn't get up to full speed. Tried several outlets all doing the same. I was reading 117V at the outlets he tried. I also cleaned the wire and reattached to both the receptacles and breakers. Re-tightened the main lugs for hots and neutrals. Still doing it. Same holds true for his compressor. This house is located close to salt water. I've seen it before where the wires were corroded and needed to be cleaned and antioxidant applied. Which I did. Anyone got any ideas what I might be missing?
Thanks.

 

[Little Bill]

A friend of mine is doing some remodeling on an existin house. When he uses his chop saw it doesn't get up to full speed. Tried several outlets all doing the same. I was reading 117V at the outlets he tried. I also cleaned the wire and reattached to both the receptacles and breakers. Re-tightened the main lugs for hots and neutrals. Still doing it. Same holds true for his compressor. This house is located close to salt water. I've seen it before where the wires were corroded and needed to be cleaned and antioxidant applied. Which I did. Anyone got any ideas what I might be missing?
Thanks.

Did you check the voltage at the panel for the main when you tightened them? Do you have access inside the meter base? If so, check there also. If you have the 117V there then it probably is POCO or if underground service ,might be a loose connection there somewhere. But the voltage readings indicate a bad/loose connection somewhere, or the transformer isn't putting out the correct voltage.

 

[kwired]

What is the voltage while attempting to run the saw or compressor? That will answer a lot more than checking voltage with no load.

Likelihood of POCO transformer not being big enough to power an appliance that operates on a 15 or 20 amp 125 volt circuit is not that great. They will probably not install much anything less than a 5kVA transformer which is more than enough for either appliance. If you have other loads running at same time it will start to make a difference though.

 

[Ponchik]

Depending on the panel that you have, you may be able to check voltage before the main breaker. If It is 117 then have your friend turn the tools ON then re-check for voltage. If the voltage drops then it is probably POCO. However, if the voltage stays around 117V then the problem is in the house somewhere. Keep in mind, check voltage while the tools are trying to turn ON.


But IMO it is a POCO loose connection.

 

[hillbilly1]

Your friend is not trying to run them off a 16 gauge extension cord?:lol: As others have said, sounds like a voltage drop problem, but does not necessacarily mean a POCO problem though, up North their bad to put a lot of houses on one small transformer, but that shouldn't be a problem in Florida. Is it a big house? Could be a long run of 14 guage he's plugged in to.

 

[scottam99]

It turned out to be POCO problem

It turned out to be POCO problem

I had my friend call the power company and they discovered the neutral was broke. Couldn't see it because an overgrown tree was in the way. All is well now!!!!

 

[Dennis Alwon]

I had my friend call the power company and they discovered the neutral was broke. Couldn't see it because an overgrown tree was in the way. All is well now!!!!

This is a classic neutral problem and if you had check the voltage on the other phase with a load it would add up to read whatever the poco voltage is there. For instance if the poco is delivering 244 volts between phases and one phase is 117v then the other phase with a load will read 127V. The addition of the two phases is 244V

 

[kwired]

This is a classic neutral problem and if you had check the voltage on the other phase with a load it would add up to read whatever the poco voltage is there. For instance if the poco is delivering 244 volts between phases and one phase is 117v then the other phase with a load will read 127V. The addition of the two phases is 244V

Is also a classic problem that there will be damaged conductors if the line is running through a tree.

 

[Dennis Alwon]

Is also a classic problem that there will be damaged conductors if the line is running through a tree.

Okay 95+% of the time around here the bad neutral is the problem with the given scenario

 

[hillbilly1]

Around the Atlanta area Georgia Power seems to have a lot of issues with the neutral burning up on their underground laterals. They have so many that they have a transformer mounted on a hand truck to temporarily supply power to the residence until they can replace it, 240 to 120/240.

 

[Little Bill]

Is also a classic problem that there will be damaged conductors if the line is running through a tree.

I just replaced a service that was pulled loose from the house when a truck hit a power pole.
The POCO engineer came out to tell me where the new drop/meter had to be. The old drop ran through a tree and all the insulation was worn off one or more of the conductors.
POCO agreed to "shave" one side of the tree off for the property owner so he didn't have to cut the whole tree down.

 

[Hv&Lv]

Around the Atlanta area Georgia Power seems to have a lot of issues with the neutral burning up on their underground laterals. They have so many that they have a transformer mounted on a hand truck to temporarily supply power to the residence until they can replace it, 240 to 120/240.

There are a couple of differnet manufacturers offering these. I have yet to go to a utility that doesn't have at least one. large companies have around 4-10

http://www.electricalmaterialscompany.com/htm/undrgrnd_srvce_quck_restor.htm

http://www.hipotronics.com/Collateral/Documents/English-US/PT30_DS_02_2012.pdf

 

[hillbilly1]

Georgia Power is the only one I have seen use it, the EMC's around the house go ahead and fix the problem while they are there. They do a whole lot more underground than GAPower does, I don't think GAPower does underground anymore, it has to be done by a subcontractor.

 

[kwired]

Around the Atlanta area Georgia Power seems to have a lot of issues with the neutral burning up on their underground laterals. They have so many that they have a transformer mounted on a hand truck to temporarily supply power to the residence until they can replace it, 240 to 120/240.

Why so much trouble with neutrals buring up. Ever since I started in this trade I have been involved in finding and repairing underground faults. Neutrals seldom fail in my experience unless they have insulation damage, and that is for aluminum conductors copper will still last practically forever. Neutrals usually fail at terminations not just at random points in the conductor without good reason.

 

[Hv&Lv]

Why so much trouble with neutrals buring up. Ever since I started in this trade I have been involved in finding and repairing underground faults. Neutrals seldom fail in my experience unless they have insulation damage, and that is for aluminum conductors copper will still last practically forever. Neutrals usually fail at terminations not just at random points in the conductor without good reason.

Wondered the same thing, but wasn't going to ask. I have never had a burned out neutral underground, normally the hot legs burning out. After all, it's 120 volts to "ground".

An interesting side note. We had a three phase open delta service that was CT metered at the pole that had been installed underground for many years. The owners noticed their bill was getting higher and higher until they decided to go with a single phase service. A few years later, (last year) we went back and had to extend the service for an addition. While we were digging, we found only three wires, not four. We dug around a bit and found the end of the fourth wire where it had been burning for 6-8 ft back in the ground. No wonder there demand and energy was so high... Fixed the wire just in case they wanted three phase back.

 

[hurk27]

I have two 20kw transformers that I use to derive a neutral from, I have about 15 trailer parks around here and the underground feeders have been spliced many times in some and it is not too uncommon to loose a neutral or hot, so if it is in the winter when the ground is frozen we just tap the transformer secondary 120-0=120 to the disconnect at the trailer to derive a neutral and leave the primary un-hooked, these are R-3 rated, the case is also bonded to the equipment ground for safety, we chain it to the disconnect to make it harder to take, I have had a lineman friend of mine borrow one a few times, but now they have got their own after seeing my set up., I have warning signs on them saying it is energized do not touch, and they are mounted on a frame and wheels from a dolly to make it easier to move around, a very good thing to have to get the power back on at a time a repair can't be made.

They didn't cost me anything as I removed them from a old grounded "B" delta service that used them for 120/240 volt loads after I installed a single phase service to take there place. they will also derive a lost hot but you will be putting all the load on one leg and as long as it is not loaded to heavy it works great to restore power till you can repair the feeder. (when the ground thaws)

 

[hillbilly1]

Why so much trouble with neutrals buring up. Ever since I started in this trade I have been involved in finding and repairing underground faults. Neutrals seldom fail in my experience unless they have insulation damage, and that is for aluminum conductors copper will still last practically forever. Neutrals usually fail at terminations not just at random points in the conductor without good reason.

I don't know either, but I have had several calls over the years that turned out to be that very problem. The only thing I can think of is lightning blowing a hole in it, and perhaps one or both of the other legs also sustaining damage, in turn burning away the neutral conductor.

 

[hurk27]

I don't know either, but I have had several calls over the years that turned out to be that very problem. The only thing I can think of is lightning blowing a hole in it, and perhaps one or both of the other legs also sustaining damage, in turn burning away the neutral conductor.

I have seen exposed neutrals go bad just like a hot will, as they turn to a white powder, but not as fast as a hot, mainly this is because of any voltage drop on the neutral will put a difference of potential between the neutral and Earth, hope that makes sense.

 

[hillbilly1]

I have seen exposed neutrals go bad just like a hot will, as they turn to a white powder, but not as fast as a hot, mainly this is because of any voltage drop on the neutral will put a difference of potential between the neutral and Earth, hope that makes sense.

Could be, those poco runs are usually undersized, and have a fair amount of voltage drop on them.

 

[hurk27]

Could be, those poco runs are usually undersized, and have a fair amount of voltage drop on them.

But they should never be bare aluminum underground, even a aluminum GEC is not allowed to be in contact with earth.

Do an experiment, take a section of bare aluminum conductor, bury it about a foot deep, then connect one end to your ground rod or service pipe, take another piece and just bury it and don't connect it to anything, bet the one connected to your service grounding dissolves much faster depending upon the neutral voltage drop., Yes I actually done this once, a long time ago, but it holds true. I did it to convince a person that a difference of potential will cause a conductor to dissolve where place in earth, this person was telling me that only DC will do this.