# Neutral Problem



## ElectricJoeNJ (Feb 24, 2011)

A break in the neutral wouldn't explain the loss of power on the A phase. What's the voltage A phase to B phase? Something tells me something is mis wired and the neutral and A phase are crossed.


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## Clarky (Sep 25, 2011)

He also said everything was ok until the wife turned on her tanning bed. Can't see how it would be miss wired. I'll go tomorrow and unhook both ends and check continuity. We've had a winter with not much snow and deep frost. Goes to show you everything underground should be in conduit.


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## Hairbone (Feb 16, 2011)

I would bet the underground was not installed with a frost loop and the wire has been streatched to the point the individual strands are like needles at some point in the wire. Turning on the tanning bed could have been the beaking point to cause the week spot to burn out.

The freezing and thawing the northeast has had this year could be a major cause of this due to the amount of ground movement we have had....the fact most of Vermont is rock doesn't help!


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## Clarky (Sep 25, 2011)

Yeh I agree when he told me it seemed to start when she turned on the tanning bed a light bulb when on. It could have been the right amount of load needed. The HO tells me the service has been spliced once already about 7 years ago.


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## Clarky (Sep 25, 2011)

What I don't understand is if there's a break on one leg of power, that explains the drop in voltage to zero, but why would the other leg read 240v to ground/ neutral?


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## Dennis Alwon (May 9, 2009)




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## hardworkingstiff (Jan 22, 2007)

The power company didn't do any transformer switch out did it?

If I understand what you are saying, it sounds like A-phase has a neutral connected to it and N has A-phase connected to it.

The only way it makes sense for that to happen is PoCo switched out the transformer and connected it wrong. Very doubtful, but what else makes sense for the symptoms reported?

Are the symptoms reported the way I understood them?


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## Southeast Power (Jan 18, 2009)

Clarky said:


> Just went on a service call."Blowing light bulbs left and right". Here 's what I found, 100amp service meter and breaker on the pole about 2-300 ft away. Owner says wire from pole to house is not in conduit. Normal voltage 120 to neutral and 240 between two hot legs. When I got there the homeowner had turned off all the breakers. I turned on all the single poles and check the voltage again. 0 volts on the a phase and 240 to ground/neutral on the B phase. Any thoughts? I think there's a break in the neutral.


Just out of curiosity, did you use a solenoid (wiggy type) tester or a digital display type?


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## Clarky (Sep 25, 2011)

I have digital Sperry meter, and I think I explained it correctly. A new pole was installed not long ago by the PO. The service is old, # 2 seu which is frayed into an old meter socket etc. I had trouble removing the meter last night to check the line side make up. I'll keep you posted.


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## Southeast Power (Jan 18, 2009)

And, what did you get with the breakers off?
Having them on would corrupt any data you were trying to get from the lateral.

Here, the POCO will set a small transformer to either establish a neutral or to use the 120 to get 240 with a neutral until the UG can be repaired or replaced.

Is the UG customer or POCO owned in that area?


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## Clarky (Sep 25, 2011)

It's a main lug panel, A phase 125v B phase 119 The UG is owned by the homeowner.


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## mbednarik (Oct 10, 2011)

Frost broke the neutral in the underground. These was probably a rock or something close to the wire and the frost drove it into the wire. Get an underground fault locator and find the break.


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## Clarky (Sep 25, 2011)

Yep seems to me the problem would be with the UG it's bad not having it in conduit. Frost is a problem this year as every year. Don't have UG fault locator, can you recommend one? Pricy?


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## hardworkingstiff (Jan 22, 2007)

Thinking about this a little more, turn off all of the breakers. Check the incoming voltages with breakers off.

If you think it's an incoming neutral problem, hook up a heat gun or hair dryer, or hot box, something that pulls a decent load on 120-volts to one leg. With the unit running, check the voltages on both phases to N and between both voltages.

If the neutral is good, the voltage will stay pretty close to the same with the load on. If the incoming neutral is defective, you should see one leg go up in voltage and the other leg go down in voltage (in reference to N, and the voltage phase to phase should remain close to the same). This is a sure sign of a defective feeder neutral.


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## Southeast Power (Jan 18, 2009)

hardworkingstiff said:


> Thinking about this a little more, turn off all of the breakers. Check the incoming voltages with breakers off.
> 
> If you think it's an incoming neutral problem, hook up a heat gun or hair dryer, or hot box, something that pulls a decent load on 120-volts to one leg. With the unit running, check the voltages on both phases to N and between both voltages.
> 
> If the neutral is good, the voltage will stay pretty close to the same with the load on. If the incoming neutral is defective, you should see one leg go up in voltage and the other leg go down in voltage (in reference to N, and the voltage phase to phase should remain close to the same). This is a sure sign of a defective feeder neutral.


He mentioned that 120 volt loads connected to this service were getting fried. 
Maybe, since they know the underground is damaged, it should be repaired until it can be replaced. If he cannot find the bad section, he should bring in a subcontractor that can and, of course, charge the HO for the services that are needed.


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## hardworkingstiff (Jan 22, 2007)

jrannis said:


> He mentioned that 120 volt loads connected to this service were getting fried.
> Maybe, since they know the underground is damaged, it should be repaired until it can be replaced. If he cannot find the bad section, he should bring in a subcontractor that can and, of course, charge the HO for the services that are needed.


I agree, but did he actually prove it was the service lateral? I'd be shocked (pun, lol) if it turned out to be something different. I've learned over the years to actually prove what you know to be the problem.


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## Clarky (Sep 25, 2011)

Here's an update. Met the Power co. field rep. Looked at the meter socket a little closer and in the daylight[ which helps], old socket not in the best of shape, pulled out the 100 amp. breaker and it showed evidence of arc and wear on" A "phase,[ the line that was going to zero under load]. Replaced it with a new breaker and everything is normal, so it seemed to be the problem but I'm not convinced that that is the end of it. My phone didn't ring last night which is good. The Power co. is suppose to relocate the primary line and the homeowner is suppose to get a new service but this has been in the works for a couple of years now. I told him he better hope it happens soon because I'd be surprised if that service makes through the winter


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## Hairbone (Feb 16, 2011)

Clarky, 

Thanks for the update. Hopefully the HO calls you back to do the job this spring...they have a tendency to forget about it when the power is back on


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## hardworkingstiff (Jan 22, 2007)

I'm confused, I thought you got a 240-volt reading from B to N. How could that happen with just a bad breaker? This was the breaker on the service pole (because I believe you said it was an MLO panel)?


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## Clarky (Sep 25, 2011)

Yea, that's right B to N 240 volts, very bizarre I still think there's a neutral problem. The Ho also told me about 6 yrs. ago the neutral had to be spliced underground. The service was done wrong from the start direct burial cable in a ditch no protection, ledge' spells trouble, surprised it's lasted this long.


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## noarcflash (Sep 14, 2011)

but theres no snow in VT, no winter to speak of. 50 degrees at stratton right now.


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## Clarky (Sep 25, 2011)

We did finally get some snow and now its 45 at 6am, very strange winter indeed . Spring can come anytime now


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## OKelectric (Mar 6, 2012)

Mr. Alwon has a Great diagram of what is happening.

The neutral may not be completely open, just a bad splice or connector, the key is to place LOAD on each phase and get a reading on BOTH phases at the same time. Very good advise "Mr Hardworkingstiff Quote:"
_
"hook up a heat gun or hair dryer, or hot box, something that pulls a decent load on 120-volts to one leg. With the unit running, check the voltages on both phases to N and between both voltages.

If the neutral is good, the voltage will stay pretty close to the same with the load on. If the incoming neutral is defective, you should see one leg go up in voltage and the other leg go down in voltage (in reference to N, and the voltage phase to phase should remain close to the same). This is a sure sign of a defective feeder neutral._ "

Most utilities use a device called a "Beast of Burden" that has two meters to see Both phases at the same time. These are great for finding open neutrals or bad/weak phase connectors etc.

http://www.metering.com/portals/hj_arnett_industries/products_and_services/10065


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## electrictim510 (Sep 9, 2008)

I hate getting to these late.  Just had one of these a few months ago. Something doesnt quite add up on this though. Sounds like there is a secondary problem somewhere...


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## RGH (Sep 12, 2011)

Dennis drew a great picture...this some what common issue in resi stuff floating or lost nuetrals....or MWBC on same phase...chase that nuet bet ya you'll have the problem:thumbsup:


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## noarcflash (Sep 14, 2011)

The voltage on LOAD 2 is entirely dependent on the resistance of LOAD 1. You'll never get a full 240v at load 2


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