Open ground/neutral


Old 03-15-11, 09:15 AM
Thread Starter
Join Date: Mar 2011
Location: US
Posts: 2
Open ground/neutral

I have an issue where when 4 circuits are turned on the voltage at the main 100A breaker will jump on one leg and decrease on the other. Typical voltage is at 118V/118V when I turn on one of these breakers it will jump to 140/80 or higher or the opposite of 80/140 depending on what leg the breaker is attached to.

I have tore into a circuit that this is happening on and see a small voltage drop until I get to the end and turn on a 60W light and I then get in the area of 95/133. I guess what I don't get is why the voltage is jumping to the other side when this is all "single phase" or 120V wiring. Last night I added a new problem to the list... I have the 4 known issues either shut off or completely disconnected from the box. Around 330 I had a neat strobe light effect going on in the kitchen light that was caused from the refrigerator compressor trying to kick on. I removed it from the plug and put it on the generator and all was "fine" with voltage still not right at 130/109. So it has to be something more than 4 circuits OR.....

The cabin has no true earth ground at this moment, but it will after I leave work this evening. And my service runs from the front house on the property which is 500+ feet away. I am thinking that it has to be between my service panel and the main panel up at the other house but how do I prove that? Will adding the earth ground help the issue, or am I completely off base and I have something totally messed up in the house that affected multiple circuits at the same time just out of the clear gray rain infested Ohio sky!

Please help my frustrated mind!
Sponsored Links
Old 03-15-11, 09:31 AM
pcboss's Avatar
Forum Topic Moderator
Join Date: Jul 2002
Location: Maryland
Posts: 14,354
You need to call the power company ASAP and have them come out and check for a loose neutral. This should be a free service available 24/7.

If they do not find anything the next call should be to an electrician to check your panel.
Old 03-15-11, 09:31 AM
Forum Topic Moderator
Join Date: Feb 2005
Location: Near Lansing, Michigan
Posts: 10,292
Now my understanding of this is that you have a service from the power company to the main house. A breaker in the main house panel feeds an underground cable 500' to the cabin. The voltage problems are observed ONLY in the cabin, not the main house? Correct? If the problems are also in the main house, then you need to call the power company ASAP.

If only the cabin, the problem is a broken, loose or corroded neutral between the cabin panel and the main panel. The obvious and easiest places to check are the neutral lugs in both panels to make sure they are tight and do not show signs of corrosion or heat damage. Also check any splice boxes that may be in the feeder, such as where it transitions from the building to underground. If the lugs are tight and any splices are good, then you can pretty much assume that there is a break in the cable underground which is now getting wet since we're coming out of winter. Do you know what kind of cable it is, direct burial, conduit, aluminum, copper?

The earth ground will not affect this problem much, but should be installed anyway for other reasons.

Let us know what you find out and we can hopefully advise from there. In the meantime, I recommend that you do not use electricity in the cabin as you risk major damage to appliances.
Old 03-15-11, 09:46 AM
Thread Starter
Join Date: Mar 2011
Location: US
Posts: 2
You are understanding this correctly. The main panel has a 100A breaker that then runs underground back to the cabin. I just made a few phone call and there is 1 splice that is known. I think that my starting place now that I know this.

The main house is having no issues at all and nothing else out of that panel is either. Other than my cabin. I have the main shut off and all appliance unplugged or running of a generator I've lost about 6 light bulbs and a surge supressor in the adventure so far!

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Display Modes