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From: John De Armond
Subject: Re: unstable, fluctuating house current?
Date: Sat, 31 Dec 2005 07:03:31 -0500
Message-ID: <>

This is usually an intermittent neutral problem.  When the voltage
goes up on one side of the line, the voltage dips on the other.  The
voltage changes as loads vary if the neutral is disconnected, high
resistance or intermittent and can't carry the neutral current.

You can check this with two meters.  Connect one meter to one side of
the incoming power and neutral and the other meter to the other
incoming line and neutral.  Then turn on and off 120 volt loads around
the house, the larger the better.  If one meter goes up and the other
goes down, then the neutral is bad somewhere.

You need to get this checked right away, as when the neutral finally
opens up completely, destructively high voltage will appear on the
lightly loaded side of the box.  Poofed appliances and even fire is

The problem is usually with the utility equipment so I'd place an
immediate call to the utility and report the problem.  Utilities tend
to jump on these kinds of problems quickly because of the potential
liability.  If their bad hardware causes a fire, especially after it's
been reported, they get to pay.  I bet they'll have someone out within
an hour or two of you calling it in.

John, retired utility dude

On 31 Dec 2005 03:18:33 -0800, "David Fraleigh" <> wrote:

>My house has been plagued by dimming lights for quite a while and
>finally yesterday I decided to explore the situation and came up with
>some results that have me stymied.   I put a voltmeter into the various
>outlets throughout the house and saw that the voltage would read at
>118v for a while and then would suddenly shift to reading 127v.  When
>this happened the lights in the room would either brighten or dim.
>This would alternate every few minutes..  I then went to my breaker
>panel and shut off my main breaker and checked the voltage situation on
>the lead in wires and saw that it was a steady 240 between tge two
>lead-ins but that the same instability occured between the individual
>leads and the ground/neutral..  (It would be 118 to ground and then
>shift to being 127 to ground every few minutes with the other wire
>reading the opposite at the same time).  I went to a neighbor who comes
>off of the same transformer and asked him if he had the same light
>dimming problems and he said he hadn't noticed it but he said that his
>light bulbs were always burning out after just a short while...  Anyway
>I am assuming that the problem is with the utility transformer but
>just wanted to know if this fluctuating current is typical of a bad
>transformer or could my ground connection possibly be causing this to
>happen...  Thanks for your help.  David

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