Missing Service Neutral... Huge Voltage Fluctuations

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CARLISSDB1

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Location
orlando, florida, orange
Background: In the process of rewiring whole house, 200amp service panel, residential, 240V, 2 legs, 1 neutral, Florida, 4/0 cable into panel, smart meter, 1 ground rod directly below meter. I am not a residential electrician but that being said I have been to lots of electrical/Instrumentaiton and control schools. I dont understand everything so dont talk down to me like I see so many people do on forums. Just keep it informational and technical.

Problem: The voltage drops in my house have become excessive to the point where I cant even run a Playstation and Television set together from one outlet. Not sure about running them from opposite legs in the system. When the refrigerator compressor starts it drags down that leg.

I ussually read approximately 90V on one leg and 140V. The balance of leg fluctuations depending on loads starting and stopping. I can remove all breakers from my panel except one (not the neutrals and grounds for the circuits I remove though) and get voltage fluctions when trying both new and old type cirucits I wired.

240v Circuits seem to run balanced

Ive checked for tightness and found some loosed connections. I have tightened everything from the load side of the service breaker all the back to the utility side of the meter. I have checked connections of the grounding rod and wiring as well. I have checked the Neutral connection points all the back to the utility side of the meter.

Ive cut many wires and removed lots of different cirucits... possibly leaving improperly incompleted ciruicts on the neutrals and grounds.

Ive taken resistance reading from the utility side of the incoming wires all the way to my incoming service wires that connect to the 200amp service breaker and get about .5 Ohms

It seems like the more current Im drawing on an individual leg (the more unbalanced between the legs) the more mismatch in voltage... as if there is a high resistance connection at some point.

I am not super familiar with grounding practices (I understand a little bit) but what I understand is the ground rod is more safety and back up stabalization related than actual flow path since its at a much higher resistance but this may be the only path I have right now which would make since for the readings Im getting (High resistance and increasing currents equals higher imbalances and voltage drops.)

Ultimately it seems like Im completly missing the service neutral (No return path except for ground) It dont see any current flowing on my neutral. I havnt tested current on the grounding rod yet.... stray grounds are probably all over my house so not sure if the grounding rod will see all the current any way.

With some light lighting loads on my system when I measure voltages on the utility side of my meter I get the same imablances leading me to think that all the connection on my side are good.

Any thought or troubleshooting suggestions would be appreciated. If i left out any infomation please ask.

Thanks
 
Only one conclusion to draw from your testing: the service neutral is bad at the meter enclosure or farther up on the POCO side. Maybe corroded concentric neutral if underground. But whatever the reason, POCO needs to fix it. Call ASAP.

Sent from my XT1585 using Tapatalk
 
161202-1155 EST

CARLISSDB1:

As GoldDigger said get power company out as soon as possible.

To study your problem do some of the following:

All measurements to follow should be with stable loading in your home that produces the 90/140 unbalance.


1. You have read 90 and 140 to neutral from opposite phases. The sum is 230 which is moderately close to your probably expected 240 line to line. When this 90/140 condition exists your neutral is offset about 1/2 the difference or 25 V from where neutral should be. When this condition exists there is about a 25 V difference between the transformer internal center tap point and the neutral bus in your main panel.

2. Ground rods to remote earth do not usually have a very low resistance. 25 ohms is the specification for maximum resistance for a single rod. In my area, a clay loam soil, I read about 10 to 20 ohms.

3. Estimate the distance from your meter to the power company transformer. This is just so we have a feeling of your layout.

4. The transformer center tap should go to a ground rod at the transformer location, close to the transformer, and separately at that center tap a neutral wire to your neutral main panel bus.

5. In your yard put two screwdrivers into the earth spaced about 12 ft apart. Use a high impedance meter like a Fluke 27 or 87 to measure the AC voltage between these two probes. In my yard this fluctuates, but is generally less than 0.2 V. I find directional differences. If you pick a random location, then you have some sort of starting point. Let us know this value later. For other measurements to be made record the values so we can have an idea of what you see.

6. Next put a probe in the ground about 12 ft from your ground rod at the house. The location should be in line with the visual path to the transformer. Read the voltage difference between the house rod and probe.

7. If possible at the transformer do the same test as in 6. Otherwise at the transformer use two probes with one as close as possible to the the transformer ground rod.

8. Pick an approximate mid point between your house and transformer and measure the 12 ft voltage between two probes. Do this in line (parallel) with the visual path between meter and transformer. Then perpendicular to the path.

These measurements will tell us something. I have never had a condition where I could do this.

Your neutral current that does not seem to be flowing thru the neutral can be flowing thru the earth and other conductive items in the earth, such as water or gas pipes.

.
 
STOP Unplug things NOW

STOP Unplug things NOW

If you keep doing what you said, you ARE going to smoke something. You talk about not being able to run TV and playstation. If that voltage inbalance grows much you WILL smoke something, I have seen it.

You are playing with fire, really. What you are doing is putting two or more loads in series and dividing the voltage.
 
I had a service request into the power company a couple of days ago... I didnt feel like they were taking it seriously when they told me they would respond within five bussiness day so I called again this morning and explained my house would probably burn down... that seemed to get there attention. Ive already desroyed a surge protecter and god only knows what other damage has occured to insulation and component in various electrical and electronic equipment. I unlpluged and turned everything off except for some lighting when im there and my 240v loads.

Thank you all for your responses

Thank you especially to Gar for all the detailed testing and measurments suggestions to perform. I will attempt to get that information incase this doesnt get resolved today.
 
Welcome to the forum!

CARLISSDB1 said:
Background: In the process of rewiring whole house, 200amp service panel, residential, 240V, 2 legs, 1 neutral, Florida, 4/0 cable into panel, smart meter, 1 ground rod directly below meter. I am not a residential electrician but that being said I have been to lots of electrical/Instrumentaiton and control schools. I dont understand everything so dont talk down to me like I see so many people do on forums. Just keep it informational and technical.

Problem: The voltage drops in my house have become excessive to the point where I cant even run a Playstation and Television set together from one outlet. Not sure about running them from opposite legs in the system. When the refrigerator compressor starts it drags down that leg.

I ussually read approximately 90V on one leg and 140V. The balance of leg fluctuations depending on loads starting and stopping. I can remove all breakers from my panel except one (not the neutrals and grounds for the circuits I remove though) and get voltage fluctions when trying both new and old type cirucits I wired.

240v Circuits seem to run balanced

Ive checked for tightness and found some loosed connections. I have tightened everything from the load side of the service breaker all the back to the utility side of the meter. I have checked connections of the grounding rod and wiring as well. I have checked the Neutral connection points all the back to the utility side of the meter.

Ive cut many wires and removed lots of different cirucits... possibly leaving improperly incompleted ciruicts on the neutrals and grounds.

Ive taken resistance reading from the utility side of the incoming wires all the way to my incoming service wires that connect to the 200amp service breaker and get about .5 Ohms

It seems like the more current Im drawing on an individual leg (the more unbalanced between the legs) the more mismatch in voltage... as if there is a high resistance connection at some point.

I am not super familiar with grounding practices (I understand a little bit) but what I understand is the ground rod is more safety and back up stabalization related than actual flow path since its at a much higher resistance but this may be the only path I have right now which would make since for the readings Im getting (High resistance and increasing currents equals higher imbalances and voltage drops.)

Ultimately it seems like Im completly missing the service neutral (No return path except for ground) It dont see any current flowing on my neutral. I havnt tested current on the grounding rod yet.... stray grounds are probably all over my house so not sure if the grounding rod will see all the current any way.

With some light lighting loads on my system when I measure voltages on the utility side of my meter I get the same imablances leading me to think that all the connection on my side are good.

Any thought or troubleshooting suggestions would be appreciated. If i left out any infomation please ask.

Thanks
Click to expand...

You have already identified the problem; you have lost the service neutral. You can run 240V only loads safely, but no 120V loads as they will not see 120V. Stop before you burn up anything else, let the POCO fix the problem.
 
I'm a full time, experienced electrician and a good troubleshooter like all the regular members here.

In my case, I don't think I have any kind of special electrical skill, until I read the OP and realized how much work we could have same this guy.
 
CARLISSDB1 said:
I had a service request into the power company a couple of days ago... I didnt feel like they were taking it seriously when they told me they would respond within five bussiness day so I called again this morning and explained my house would probably burn down... that seemed to get there attention. Ive already desroyed a surge protecter and god only knows what other damage has occured to insulation and component in various electrical and electronic equipment. I unlpluged and turned everything off except for some lighting when im there and my 240v loads.

Thank you all for your responses

Thank you especially to Gar for all the detailed testing and measurments suggestions to perform. I will attempt to get that information incase this doesnt get resolved today.
Click to expand...
.
if you unplug everything, and turn everything off.....

there is no path from one hot leg to the other one,
across the open or nonexistent neutral.

if it was me, i'd be curious, and get a blow dryer, and see
if i could find an outlet it would run on, scooch up on the
roof with an amprobe, and find what leg had that 1,800
watts on it, and see how much of it was coming back up
the riser on the neutral.... then i'd go look for it's path
to ground.

i'd also document any damage done, in the event this
turns out to be a poco issue. they pay to repair and replace
stuff they burn out. not willingly, but they do.

as for that burned out surge protector, be glad for it.
it's probably cheaper than what was plugged into it.

and thanks for reminding me, i need to put the whole
house surge protector that's sitting on my workbench in
tomorrow. i keep forgetting.
 
Fulthrotl said:
.
if you unplug everything, and turn everything off.....

there is no path from one hot leg to the other one,
across the open or nonexistent neutral.

if it was me, i'd be curious, and get a blow dryer, and see
if i could find an outlet it would run on, scooch up on the
roof with an amprobe, and find what leg had that 1,800
watts on it, and see how much of it was coming back up
the riser on the neutral.... then i'd go look for it's path
to ground.

i'd also document any damage done, in the event this
turns out to be a poco issue. they pay to repair and replace
stuff they burn out. not willingly, but they do.

as for that burned out surge protector, be glad for it.
it's probably cheaper than what was plugged into it.

and thanks for reminding me, i need to put the whole
house surge protector that's sitting on my workbench in
tomorrow. i keep forgetting.
Click to expand...

I feel like Ive balanced the loads sufficiently to avoid any further damage for what I absolutley need. I just leave the lights on that balance each other out. All my electronics are unpluged and rest of stuff have open breakers. The only risk I feel like I have right now is the refrigerator. When I get home tonight I might unplug that depending on if they can or cannot fix it soon. The techs are there but Im at work. Hopefully its a loose connection somewhere and quick fix and not a whole replacement. Hopefully I dont have to go through the claims process but well see.
 
Fulthrotl said:
.
if you unplug everything, and turn everything off.....

there is no path from one hot leg to the other one,
across the open or nonexistent neutral.

if it was me, i'd be curious, and get a blow dryer, and see
if i could find an outlet it would run on, scooch up on the
roof with an amprobe, and find what leg had that 1,800
watts on it, and see how much of it was coming back up
the riser on the neutral.... then i'd go look for it's path
to ground.

i'd also document any damage done, in the event this
turns out to be a poco issue. they pay to repair and replace
stuff they burn out. not willingly, but they do.

as for that burned out surge protector, be glad for it.
it's probably cheaper than what was plugged into it.

and thanks for reminding me, i need to put the whole
house surge protector that's sitting on my workbench in
tomorrow. i keep forgetting.
Click to expand...

Yeah that $50 surge protector Ive had for 10 years saved about $1800 worth of electronics... thats a first for me but Im pretty cautious with electronic equipment and using surge protectors
 
I certainly don't want you to think I'm talking down to you, but.....most folks are not familiar with POCO procedures. I am a retired utility meter/relay tech and have worked at several different POCO's. Utilities are providing a service and they try to do the best they can with the resources they have. But they can't help if they are not notified of problems until you walk in the door with a "smoked" TV or some such and expect a new one on the spot. In my experience, bad neutrals are the cause of the vast majority of equipment damage claims. Most are not the utility, however. Many are panel loose connections, but occasionally there is service riser corrosion at the weatherhead, etc. As stated above, don't turn anything 120V on until you get it fixed. If the POCO investigates, they will probably show up with a "Beast of Burden" to test your service. That is a device connected to the line side of the service disconnect (which only the POCO should access, since you are ahead of any fault protection) and loads each line with a "hair dryer" type of load to measure voltage changes during line to neutral load conditions. Loads can be up to 80A. The results will be as follows. Line loaded, voltage to neutral drops slightly and unloaded line to neutral rises only slightly, service is OK. If either line drops voltage under load while the opposite line remains fairly constant, there is a line impedance problem. If one line drops under load and the other rises, then it's a neutral impedance problem. If the POCO test shows no problem, they are usually not authorized to go into your home and test at any main or sub-panels. But, you need to find out where the problem is before you can proceed. Good luck. I would definitely have the POCO investigate before I spent any money on an electrician. Not "talking down" to you, but service side fault currents can be VERY high, so if you're not comfortable working ahead of breakers, and don't have the proper PPE, leave it to the pros. I've investigated several fatalities, and it was always preventable. Just my 2 cents, though.
 
Meternerd has got it. I am a meter tech and when I get calls that say my lights are getting bright and then dim or my lights get bright and then blow it is almost always a neutral issue. The utility will come out and check it with a neutral tester. Most good techs will check all of the connections in your meter base at your riser and ground rod. I have actually gone out to check a service with a neutral tester "beast" before and when I flipped the switch one leg went completely to zero and the other went to 240v. Don't be surprised either if you get just one guy to come out from the power company first to talk with you and check your service. If he finds something beyond a loose connection he may need to call a crew.
 
meternerd said:
Most are not the utility, however. Many are panel loose connections, but occasionally there is service riser corrosion at the weatherhead, etc.
Click to expand...
Hmmm, in my 40 plus years I have found more lost neutrals on the POCO connections at the weatherhead than in a panel, probably 10 to 1.

Roger
 
CARLISSDB1 said:
Background: In the process of rewiring whole house, 200amp service panel, residential, 240V, 2 legs, 1 neutral, Florida, 4/0 cable into panel, smart meter, 1 ground rod directly below meter. I am not a residential electrician but that being said I have been to lots of electrical/Instrumentaiton and control schools. I dont understand everything so dont talk down to me like I see so many people do on forums. Just keep it informational and technical.

Problem: The voltage drops in my house have become excessive to the point where I cant even run a Playstation and Television set together from one outlet. Not sure about running them from opposite legs in the system. When the refrigerator compressor starts it drags down that leg.

I ussually read approximately 90V on one leg and 140V. The balance of leg fluctuations depending on loads starting and stopping. I can remove all breakers from my panel except one (not the neutrals and grounds for the circuits I remove though) and get voltage fluctions when trying both new and old type cirucits I wired.

240v Circuits seem to run balanced

Ive checked for tightness and found some loosed connections. I have tightened everything from the load side of the service breaker all the back to the utility side of the meter. I have checked connections of the grounding rod and wiring as well. I have checked the Neutral connection points all the back to the utility side of the meter.

Ive cut many wires and removed lots of different cirucits... possibly leaving improperly incompleted ciruicts on the neutrals and grounds.

Ive taken resistance reading from the utility side of the incoming wires all the way to my incoming service wires that connect to the 200amp service breaker and get about .5 Ohms

It seems like the more current Im drawing on an individual leg (the more unbalanced between the legs) the more mismatch in voltage... as if there is a high resistance connection at some point.

I am not super familiar with grounding practices (I understand a little bit) but what I understand is the ground rod is more safety and back up stabalization related than actual flow path since its at a much higher resistance but this may be the only path I have right now which would make since for the readings Im getting (High resistance and increasing currents equals higher imbalances and voltage drops.)

Ultimately it seems like Im completly missing the service neutral (No return path except for ground) It dont see any current flowing on my neutral. I havnt tested current on the grounding rod yet.... stray grounds are probably all over my house so not sure if the grounding rod will see all the current any way.

With some light lighting loads on my system when I measure voltages on the utility side of my meter I get the same imablances leading me to think that all the connection on my side are good.

Any thought or troubleshooting suggestions would be appreciated. If i left out any infomation please ask.

Thanks
Click to expand...

Thanks everyone for there comments, suggestions, advice and help. It was indeed my neutral on the utility side of my meter. They hooked up a temp wire until a more permenant repair can be made. I will finally sleep easy tonight. I would have never thought this would be such a common failure (until all the reading i have done) and thougt is was probably my fault since i was rewiring my house at the time it happens. Had just finished a sub panel at the exact same time it failed (when i turned breaker back on). It was dark and the guys running the wire didnt know where the point of failure was and im still curious to find out. Thanks again and goodnight to all.
 
roger said:
Hmmm, in my 40 plus years I have found more lost neutrals on the POCO connections at the weatherhead than in a panel, probably 10 to 1.

Roger
Click to expand...

:thumbsup:

Yeah I was baffled on that one, the dry location connections seem to do a lot better than the wet location connections.
 
roger said:
Hmmm, in my 40 plus years I have found more lost neutrals on the POCO connections at the weatherhead than in a panel, probably 10 to 1.

Roger
Click to expand...
Hypress connectors seem to never fail. If there is a split bolt or other mechanical connector there, that is often one of the first places I check.

Broken or improper hanger on the messenger wire (which is also the neutral) is also a common failure point or if it is rubbing on tree branches or other obstacles.
 
Michael15956 said:
I'm a full time, experienced electrician and a good troubleshooter like all the regular members here.

In my case, I don't think I have any kind of special electrical skill, until I read the OP and realized how much work we could have saved this guy.
Click to expand...

I agree it doesn't take long for an experienced electrician to know there is bad neutral and to figure out it's on the utility side.

When you call the utilities and let them know that you have checked out the problem and it's on their side they normally get there pretty quick.

If you figure out the cost of a service call and the possible problems with not getting the neutral repaired promptly it' not such a bad investment.

This is just my opinion but I think when you find a bad neutral on the utility side the utility should pay for the service call.
 
growler said:
This is just my opinion but I think when you find a bad neutral on the utility side the utility should pay for the service call.
Click to expand...
Unless a line crew made wrong connections, and damages occur immediately afterward they seem to get by calling it an act of God type of situation. Most cases you may have to take it to court to get a claim, and it may cost you more then it is worth to do that. If damages are high enough in cost, leave it up to your insurance to pursue collecting damages from the POCO, if that is what they want to do.
 
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