On Jan 3, 11:54*am, bud-- wrote:
coloradotrout wrote:
On Jan 1, 3:28 pm, bud-- wrote:
coloradotrout wrote:
On Dec 26, 7:55 am, "John Grabowski" wrote:
"coloradotrout" wrote in message
...
On Dec 24, 10:20 pm, metspitzer wrote:
On Wed, 24 Dec 2008 20:48:50 -0500, "Twayne"
wrote:
DO NOT TAKE CHANCES WITH YOUR LIFE! If any of this is beyond your
abilities/experience, don't do it!
Or get it on video.
Just kidding.
Merry Christmas
I will certainly have a look.
The 220V circuits are 3 wire - black, white (red) and bare (earth
ground).
I was meticulous when I wired in the cicuits - d, f, and g. *But it
almost seems certain that the issue must be in the 3 outlet 220V
circuit. * When I turn off it's breaker, all the other 110v outlets
test OK. *The outlets are 20A outlets. *They are wired one above the
other, 3 in a row vertically. *If I switched black and white (red)
from one side of the outlet to the other would that cause any issues?
Shouldn't right? * It's still 110V on either side - should make no
difference which side is black and which is white (red). * At the
breaker - black goes to one terminal of the breaker and white goes to
the other - and ground goes to the ground block (not the neutral
block).
I suppose one of those 20A 220v outlets could have a problem?
* My first thought is that there may be a problem with whatever is plugged
into those outlets. *You didn't mention if you had disconnected the
equipment from the receptacles when you did your testing.
Problem Identified - Problem Solved
On that suspect 220v circuit there was one outlet that had a ground
wire that was poking into the white (hot in the case of 220v).
Lesson -- clip off any wires that extend beyond the outlet. *I had
just wrapped the ground around the outlet post and tightened the screw
down, but left 3/8" or so sticking out. *That little amount, when
pushed into the box, was able to penetrate into the white.
So , in essense, my ground circuit had 110v on it.

Nice to hear what the problem was.

But you can't have 110V on a ground unless you have a bad ground
connection back the service. If the ground was continuous there would be
high current which would trip the breaker or burn some wires open
(probably at the point of your fault). That is the point of having a ground.

Understand. *So, all the circuits check out OK now (the tester does
not work on the 220v ones however).

If the simple plug-in 3-lite testers indicate a problem, there probably
is one.

They can not reliably indicate there is no problem. A high resistance
ground is one of the problems they can not detect (they don't use enough
current when testing).

I was thinking the same -- if one
side of the 220 was grounded, it would have tripped the 220v breaker,
but it did not. * So that suggests the ground may have an open
somewhere - correct? *Hmmm.. * *another mystery.

Any receptacle that gave a "funny" indication had a bad ground. It could
be a circuit or the whole panel.

Not only are some outlets not grounded, if a failure at one outlet makes
that ground "hot" many other outlet grounds are "hot". Real bad condition..

To test the ground, connect a light bulb from hot to ground. If the bulb
does not light the ground is open. The bulb should light at full brightness.

Makes be wonder if
the box has a good earth ground or not.

It is not an earth ground problem.

The "ground" wires return to the service. At that point there is a
connection between the "grounds" and the incoming service neutral. (This
is typically a screw from the neutral bus to the enclosure.) On a fault,
like yours, the ground wires go back to the service panel, connect to
the service neutral, and go to the power transformer. That gives a high
current path that will trip a circuit breaker. This is a main function
of "ground" wires, and will happen without an earth connection.

Connection of "ground" (and neutral) wires to the earth keeps a low
potential with respect to the earth. If the "ground wire"-neutral bond
at the service is missing, there will be some return through the
earthing electrode, through the earth, to the earthing electrode at the
transformer. If you had a quite good resistance to earth of 10 ohms,
your fault (120V to earth) would produce a current of 12 amps - not
likely to trip a 15A breaker - there would be a significant delay even
if the breaker was fully loaded.

--
bud--- Hide quoted text -

- Show quoted text -

Bud,

So I should look in my panel and see that the neutral is grounded to
the box?

I thought I recall seeing 3 large wires coming into the box - hot,
hot, and neutral. The box itself then has a ground bar and two
neutral bars ( I think). I do not recall seeing any neutral to box
connection.