Hi All,

I just installed a ceiling light in my kitchen, and now I measure a
47V (AC) difference between the light's ground wire and its neutral
wire. Is this normal, or could the ground wire be floating?

Thank you,

-Bill

Bill wrote:
Hi All,

I just installed a ceiling light in my kitchen, and now I measure a
47V (AC) difference between the light's ground wire and its neutral
wire. Is this normal, or could the ground wire be floating?

Thank you,

-Bill


No, that is certainly not normal. Check the neutral and ground
connections in the panel, as well as anything that uses those horrible
spring loaded push-in terminals, those are notorious for developing bad
connections, IMO they ought to be banned.

Bill wrote:
Hi All,

I just installed a ceiling light in my kitchen, and now I measure a
47V (AC) difference between the light's ground wire and its neutral
wire. Is this normal, or could the ground wire be floating?

Thank you,

-Bill

If you are using a digital voltmeter, you could be seeing an open
circuit on the ground wire at the fixture. However, that being said, if
you have an open neutral at the breaker box or service entrance, you
have a serious condition warranting that you call for the utility
service or an electrician immediately. Fire and death by electrocution
are possibilities. Do any appliances or lights behave as the voltage is
too high or too low? If so, you have a serious problem.

--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P

"Bill" wrote in message
...

Hi All,

I just installed a ceiling light in my kitchen, and now I measure a
47V (AC) difference between the light's ground wire and its neutral
wire. Is this normal, or could the ground wire be floating?

Thank you,

-Bill


If the fixture is working then leave it alone. If the fixture is not
working remove it and hook up a rubber pigtail socket and bulb to the
ceiling wiring to check it. Stop using your voltmeter. I'm guessing that
you are checking the voltage between the neutral with the fixture lit and
the grounding conductor.

James Sweet wrote:

Bill wrote:
Hi All,

I just installed a ceiling light in my kitchen, and now I measure a
47V (AC) difference between the light's ground wire and its neutral
wire. Is this normal, or could the ground wire be floating?

Thank you,

-Bill

No, that is certainly not normal. Check the neutral and ground
connections in the panel, as well as anything that uses those horrible
spring loaded push-in terminals, those are notorious for developing bad
connections, IMO they ought to be banned.

I concur. Work your way back from the fixture with a voltmeter and see
where you lose that 47V.

Story about spring loaded terminals: I helped a friend diagnose a
flickering lights problem at his house. It seems that one circuit,
heavily loaded was fed through a receptacle using these spring loaded
contacts (in one set and out the other). It was the first device on the
branch circuit and was easy to diagnose. Although nothing was plugged
into it, the device was hot (thermally)!

--
Paul Hovnanian
------------------------------------------------------------------
On a clear disk, you can seek forever.

Story about spring loaded terminals: I helped a friend diagnose a
flickering lights problem at his house. It seems that one circuit,
heavily loaded was fed through a receptacle using these spring loaded
contacts (in one set and out the other). It was the first device on the
branch circuit and was easy to diagnose. Although nothing was plugged
into it, the device was hot (thermally)!


I just had a circuit go dead in my house the other night, tracked it
down to the very same problem. I decided that while I'd already messed
up all the clocks finding the right breaker, I'd use that opportunity to
shut things down and replace the last few of the original upstairs
receptacles I hadn't gotten to yet and in that process I found one more
blackened corroded wire that had been arcing and was a failure or fire
waiting to happen.

The contact area is simply too small, it heats up and then the spring
loses tension and it starts to arc and heat up more. These things are a
safety nightmare, I will never understand why the NEC is so nitpicky
about some things yet lets major issues like these slide right by. Spend
a few bucks more for decent receptacles, it's cheap insurance and peace
of mind, not to mention plugs won't start falling out in a few years.

"Bill" wrote in message
...

Hi All,

I just installed a ceiling light in my kitchen, and now I measure a
47V (AC) difference between the light's ground wire and its neutral
wire. Is this normal, or could the ground wire be floating?

Thank you,

-Bill
More than a few volts between the neutral and ground indicates that they are
not connected together. If they are properly connected together in the
entrance panel and the fixture is working, the ground is disconnected
somewhere (floating). Use a bulb in a pigtail socket to check this. It
should light from hot to neutral and from hot to ground. Be careful as a
floating ground can cause dangerous voltages to appear on supposedly
grounded metal parts, especially if you connect a load from hot to the
ground.

Don Young

James Sweet wrote:
Bill wrote:
Hi All,

I just installed a ceiling light in my kitchen, and now I measure a
47V (AC) difference between the light's ground wire and its neutral
wire. Is this normal, or could the ground wire be floating?

Thank you,

-Bill


No, that is certainly not normal. Check the neutral and ground
connections in the panel, as well as anything that uses those horrible
spring loaded push-in terminals, those are notorious for developing bad
connections, IMO they ought to be banned.

Does any device use push ins for ground? I have not seen any (that
doesn't mean they don't exist, I'm asking an honest question)

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

James Sweet wrote:


Story about spring loaded terminals: I helped a friend diagnose a
flickering lights problem at his house. It seems that one circuit,
heavily loaded was fed through a receptacle using these spring loaded
contacts (in one set and out the other). It was the first device on the
branch circuit and was easy to diagnose. Although nothing was plugged
into it, the device was hot (thermally)!


I just had a circuit go dead in my house the other night, tracked it
down to the very same problem. I decided that while I'd already messed
up all the clocks finding the right breaker, I'd use that opportunity to
shut things down and replace the last few of the original upstairs
receptacles I hadn't gotten to yet and in that process I found one more
blackened corroded wire that had been arcing and was a failure or fire
waiting to happen.

The contact area is simply too small, it heats up and then the spring
loses tension and it starts to arc and heat up more. These things are a
safety nightmare, I will never understand why the NEC is so nitpicky
about some things yet lets major issues like these slide right by. Spend
a few bucks more for decent receptacles, it's cheap insurance and peace
of mind, not to mention plugs won't start falling out in a few years.

I'm not sure if these things are still available. All I've seen at the
local Home Despot are screw terminal types. Either the basic 'wrap the
wire around the screw' or the 'stick the straight wire in the hole and
apply pressure via an internal screw and clamp'. None depending on a
spring alone.

Besides that, I don't like using receptacles for a feed-thru. Pigtails
wherever possible, unless the box is too small to contain the extra
wires and nuts.

--
Paul Hovnanian
------------------------------------------------------------------
Happily doing the work of 3 Men ... Moe, Larry & Curly

In article ,
"John Grabowski" wrote:

If the fixture is working then leave it alone. If the fixture is not
working remove it and hook up a rubber pigtail socket and bulb to the
ceiling wiring to check it. Stop using your voltmeter. I'm guessing that
you are checking the voltage between the neutral with the fixture lit and
the grounding conductor.

I think this is scary advice. The OP seems a bit out of his depth here.
He would be better advised to hire a competent electrician to get to the
bottom of this situation. There may be a perfectly rational explanation
for the voltage between N and G, but it also is an indication of a truly
unsafe condition.

When my son bought his house a few years ago, I found out that the
electrical system was upgraded by using grounding receptacles. Some were
found in the bathroom. The only problem was that no grounding conductor
was present. Everything would work as well as could be expected until
you become the grounding conductor. There probably are many such gotchas
almost everywhere.

Bill

--
Private Profit; Public Poop! Avoid collateral windfall!

Don Young wrote:

"Bill" wrote in message
...

Hi All,

I just installed a ceiling light in my kitchen, and now I measure a
47V (AC) difference between the light's ground wire and its neutral
wire. Is this normal, or could the ground wire be floating?

Thank you,

-Bill
More than a few volts between the neutral and ground indicates that they are
not connected together. If they are properly connected together in the
entrance panel and the fixture is working, the ground is disconnected
somewhere (floating). Use a bulb in a pigtail socket to check this. It
should light from hot to neutral and from hot to ground. Be careful as a
floating ground can cause dangerous voltages to appear on supposedly
grounded metal parts, especially if you connect a load from hot to the
ground.

Don Young

Worst case is that the test light will illuminate connected from hot to
neutral. But it will be dim due to high voltage drop and the person
doing the test will not notice. A high resistance connection will get
HOT under load and may create a fire hazard. If a hot or neutral is wide
open, nothing works, but nothing gets hot.

--
Paul Hovnanian
------------------------------------------------------------------
If everything is coming your way then you're in the wrong lane.

Nate Nagel wrote:
James Sweet wrote:
Bill wrote:
Hi All,

I just installed a ceiling light in my kitchen, and now I measure a
47V (AC) difference between the light's ground wire and its neutral
wire. Is this normal, or could the ground wire be floating?

Thank you,

-Bill


No, that is certainly not normal. Check the neutral and ground
connections in the panel, as well as anything that uses those horrible
spring loaded push-in terminals, those are notorious for developing
bad connections, IMO they ought to be banned.

Does any device use push ins for ground? I have not seen any (that
doesn't mean they don't exist, I'm asking an honest question)

nate



No, but they do for neutral, and if neutral is floating at all above
ground, you'll measure a voltage between them. Of course the light will
be dim in that case too.

First if you are using a modern digital meter, it may be giving
false reading because it is very sensitive. In addition you may be
getting odd readings because you are effectively measuring the load on
the circuit. Try removing the lamp and use an analog meter and see
that happens.

"Salmon Egg" wrote in message
...
In article ,
"John Grabowski" wrote:

If the fixture is working then leave it alone. If the fixture is not
working remove it and hook up a rubber pigtail socket and bulb to the
ceiling wiring to check it. Stop using your voltmeter. I'm guessing
that
you are checking the voltage between the neutral with the fixture lit and
the grounding conductor.

I think this is scary advice. The OP seems a bit out of his depth here.
He would be better advised to hire a competent electrician to get to the
bottom of this situation. There may be a perfectly rational explanation
for the voltage between N and G, but it also is an indication of a truly
unsafe condition.

When my son bought his house a few years ago, I found out that the
electrical system was upgraded by using grounding receptacles. Some were
found in the bathroom. The only problem was that no grounding conductor
was present. Everything would work as well as could be expected until
you become the grounding conductor. There probably are many such gotchas
almost everywhere.


*Granted. However the OP has failed to post any details. He didn't say if
the fixture was working correctly or not. He didn't say how he came to find
the voltage discrepancy. He didn't say why he changed the light fixture. I
just made some assumptions that everything was working fine and he was just
playing around with his volt meter. If the OP cares to furnish more details
then perhaps my response will be different

James Sweet wrote:


Story about spring loaded terminals: I helped a friend diagnose a
flickering lights problem at his house. It seems that one circuit,
heavily loaded was fed through a receptacle using these spring loaded
contacts (in one set and out the other). It was the first device on the
branch circuit and was easy to diagnose. Although nothing was plugged
into it, the device was hot (thermally)!


I just had a circuit go dead in my house the other night, tracked it
down to the very same problem. I decided that while I'd already messed
up all the clocks finding the right breaker, I'd use that opportunity to
shut things down and replace the last few of the original upstairs
receptacles I hadn't gotten to yet and in that process I found one more
blackened corroded wire that had been arcing and was a failure or fire
waiting to happen.

The contact area is simply too small, it heats up and then the spring
loses tension and it starts to arc and heat up more. These things are a
safety nightmare, I will never understand why the NEC is so nitpicky
about some things yet lets major issues like these slide right by. Spend
a few bucks more for decent receptacles, it's cheap insurance and peace
of mind, not to mention plugs won't start falling out in a few years.

The problem isn't the NEC. The problem is UL allows these atrocities.
At least the hole isn't big enough for #12 wire anymore.

--
bud--

On Dec 9, 6:37*pm, Bill wrote:
Hi All,

* *I just installed a ceiling light in my kitchen, and now I measure a
47V (AC) difference between the light's ground wire and its neutral
wire. *Is this normal, or could the ground wire be floating?

Thank you,

-Bill

If its a DVM then yes you see that often. In fact, I would be more
worried if I saw 0 volts between neutral and ground when using a
DVM... because that meant that somehow my neutral got grounded and now
my ground is a load carrier (a situation you never want to see). Get
a low-impedance analog VOM meter and re-test it, you will see a much
lower or zero volts. Try a neon tester, it probably wont light. The
47V with a DVM is most likely induction current easily detected by the
DVM which has a very high impedance able to detect small current.

In article ,
"John Grabowski" wrote:

*Granted. However the OP has failed to post any details. He didn't say if
the fixture was working correctly or not. He didn't say how he came to find
the voltage discrepancy. He didn't say why he changed the light fixture. I
just made some assumptions that everything was working fine and he was just
playing around with his volt meter. If the OP cares to furnish more details
then perhaps my response will be different


That is why I thought that OP was out of his league. Apparently he
thought so as well because he hired a presumably competent contractor. I
think that showed good sense on a situation that many people would feel
falsely competent to handle.

A few years ago, I hired a competent electrician to track down and
replace a poorly connected neutral conductor. I had diagnosed the
problem but had not pin-pointed where it was. That turned out to have
been a good decision because he was experienced in such matters and I
was not. I am confident that I could have located the problem but it
would take ten times as long and I would not know the best way to
correct it.

Bill

--
Private Profit; Public Poop! Avoid collateral windfall!

On Dec 10, 2:44*pm, Salmon Egg wrote:
In article ,
*"John Grabowski" wrote:

*Granted. *However the OP has failed to post any details. *He didn't say if
the fixture was working correctly or not. *He didn't say how he came to find
the voltage discrepancy. *He didn't say why he changed the light fixture. *I
just made some assumptions that everything was working fine and he was just
playing around with his volt meter. *If the OP cares to furnish more details
then perhaps my response will be different

That *is why I thought that OP was out of his league. Apparently he
thought so as well because he hired a presumably competent contractor. I
think that showed good sense on a situation that many people would feel
falsely competent to handle.

A few years ago, I hired a competent electrician to track down and
replace a poorly connected neutral conductor. I had diagnosed the
problem but had not pin-pointed where it was. That turned out to have
been a good decision because he was experienced in such matters and I
was not. I am confident that I could have located the problem but it
would take ten times as long and I would not know the best way to
correct it.

Bill

--
Private Profit; Public Poop! Avoid collateral windfall!

Oops I missed the post that the OP found the open ground, but I have
seen all kinds of wierd readings on normal wiring if you use a DVM.
Also neutral problems scare me more than working on hot leads. Thats
because hot leads always simply terminate and their breakers are 1 to
1. So you would have to consiously put your body "in series" with the
current flow even if you are dumb enough to not trip the breaker.

Whereas neutrals travel all over the house, so if you open a wire cap
on a bundle of neutrals that you find in a box somewhere, even though
your breaker is tripped on the circuit you think is correct, that
bundle may still have some current flow from a different branch that
is live. So if you happen to separate and grab two of those neutrals
as you remove the wire cap, your body immediately is put in series
with a load carrying wire, not good. Being in series with a neutral
carrying 10 amps is instant death.

Neutrals actually require more safety caution than working with
specific hot leads especially when unbundling wire caps to insert
another pigtail.

In article ,
says...
In article ,
"John Grabowski" wrote:

If the fixture is working then leave it alone. If the fixture is not
working remove it and hook up a rubber pigtail socket and bulb to the
ceiling wiring to check it. Stop using your voltmeter. I'm guessing that
you are checking the voltage between the neutral with the fixture lit and
the grounding conductor.

I think this is scary advice. The OP seems a bit out of his depth here.
He would be better advised to hire a competent electrician to get to the
bottom of this situation. There may be a perfectly rational explanation
for the voltage between N and G, but it also is an indication of a truly
unsafe condition.

Exactly right. I might note that a high impedance voltmeter isn't a
good tool here.

When my son bought his house a few years ago, I found out that the
electrical system was upgraded by using grounding receptacles. Some were
found in the bathroom. The only problem was that no grounding conductor
was present. Everything would work as well as could be expected until
you become the grounding conductor. There probably are many such gotchas
almost everywhere.

That's what GFCIs are for. Place a GFCI upstream of these outlets
and all is well. Place stickers on the ungrounded outlets marking
them as ungrounded and you're even in compliance. Often, adding the
grounded conductor just isn't practical.

--
Keith

bud-- wrote:
James Sweet wrote:


Story about spring loaded terminals: I helped a friend diagnose a
flickering lights problem at his house. It seems that one circuit,
heavily loaded was fed through a receptacle using these spring loaded
contacts (in one set and out the other). It was the first device on the
branch circuit and was easy to diagnose. Although nothing was plugged
into it, the device was hot (thermally)!


I just had a circuit go dead in my house the other night, tracked it
down to the very same problem. I decided that while I'd already messed
up all the clocks finding the right breaker, I'd use that opportunity
to shut things down and replace the last few of the original upstairs
receptacles I hadn't gotten to yet and in that process I found one
more blackened corroded wire that had been arcing and was a failure or
fire waiting to happen.

The contact area is simply too small, it heats up and then the spring
loses tension and it starts to arc and heat up more. These things are
a safety nightmare, I will never understand why the NEC is so nitpicky
about some things yet lets major issues like these slide right by.
Spend a few bucks more for decent receptacles, it's cheap insurance
and peace of mind, not to mention plugs won't start falling out in a
few years.

The problem isn't the NEC. The problem is UL allows these atrocities. At
least the hole isn't big enough for #12 wire anymore.


In Tallahassee a few years ago a local insurance agent had several
unexplained electrical fires in his office suite. Photos in the paper
showed an electrical outlet with the wall above it burned as if the
romex cable had burned. He hired an EE professor from FSU who postulated
that EM waves from a nearby cellular tower were concentrating energy
into his office! I think more likely he had those backstabbed outlets
and the office workers were plugging an electric heater into the outlets.



--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P

RFI-EMI-GUY wrote:
bud-- wrote:
James Sweet wrote:


Story about spring loaded terminals: I helped a friend diagnose a
flickering lights problem at his house. It seems that one circuit,
heavily loaded was fed through a receptacle using these spring loaded
contacts (in one set and out the other). It was the first device on the
branch circuit and was easy to diagnose. Although nothing was plugged
into it, the device was hot (thermally)!


I just had a circuit go dead in my house the other night, tracked it
down to the very same problem. I decided that while I'd already
messed up all the clocks finding the right breaker, I'd use that
opportunity to shut things down and replace the last few of the
original upstairs receptacles I hadn't gotten to yet and in that
process I found one more blackened corroded wire that had been arcing
and was a failure or fire waiting to happen.

The contact area is simply too small, it heats up and then the spring
loses tension and it starts to arc and heat up more. These things are
a safety nightmare, I will never understand why the NEC is so
nitpicky about some things yet lets major issues like these slide
right by. Spend a few bucks more for decent receptacles, it's cheap
insurance and peace of mind, not to mention plugs won't start falling
out in a few years.

The problem isn't the NEC. The problem is UL allows these atrocities.
At least the hole isn't big enough for #12 wire anymore.


In Tallahassee a few years ago a local insurance agent had several
unexplained electrical fires in his office suite. Photos in the paper
showed an electrical outlet with the wall above it burned as if the
romex cable had burned. He hired an EE professor from FSU who postulated
that EM waves from a nearby cellular tower were concentrating energy
into his office! I think more likely he had those backstabbed outlets
and the office workers were plugging an electric heater into the outlets.





I've seen nearly this exact scenario, only the wire lost contact and
opened the circuit before it got that far and it wasn't a heater, it was
just several computers. EM waves from a cellular tower? That's ludicrous!

On Dec 9, 3:37*pm, Bill wrote:
Hi All,

* *I just installed a ceiling light in my kitchen, and now I measure a
47V (AC) difference between the light's ground wire and its neutral
wire. *Is this normal, or could the ground wire be floating?

Thank you,

-Bill

Try:
http://www.electrician2.com/practice...qp972/gn8.html