Hello,

Installing under cabinet lights and upgrading 30yr old switches and
receptacles in the kitchen when something I've never encountered
happen.

I have a neon-tester I use to make sure there is no power before doing
any work. I'm not sure if this is the official name for it, but it's a
very convenient tool I've had for a couple years now. For example, I
can hold one metal tip to a live black wire and put the other tip to
the neutral white wire and the light at the end of the tester lights
up. Or, if there is not a white neutral wire like a single-pole switch,
I can put the other metal tip on my finger and the light just barely
lights up.

Well, when about to replace a 30 old S.P. by my kitchen sink I went to
check to see if there was power running to the switch. I grabbed my
neon-test, put one metal tipped needle on the black wire screw and
tapped my finger on the other and the light lit up slightly for a brief
second before POP! and a puff of smoke.

After I made sure I still had my eye-brows I looked and part of the
screw is melted, the side of the switch is burnt black and my beloved
neon-testers metal tip is melted.

What happen?

Well, I theorized the screw was loose on the side of the switch and
think an arc was created and it was a one time deal.

Well, I was wrong, because in the next two days, all when working on
the same wall in the kitchen (two circuits), I've had three more loud
pops and a quick burst of light when trying to test.

I thought maybe my neon-tester had gone bad, but it even happen with a
new tester.

Any comments/suggestions? I do plan on calling a certified electrician
to come check everything out b/c in my three years of doing electrical
work around the house I've never had this happen. I do though want to
learn what is happening.

Thanks!

Native wrote:
Hello,

Installing under cabinet lights and upgrading 30yr old switches and
receptacles in the kitchen when something I've never encountered
happen.

I have a neon-tester I use to make sure there is no power before doing
any work. I'm not sure if this is the official name for it, but it's a
very convenient tool I've had for a couple years now. For example, I
can hold one metal tip to a live black wire and put the other tip to
the neutral white wire and the light at the end of the tester lights
up. Or, if there is not a white neutral wire like a single-pole switch,
I can put the other metal tip on my finger and the light just barely
lights up.

Well, when about to replace a 30 old S.P. by my kitchen sink I went to
check to see if there was power running to the switch. I grabbed my
neon-test, put one metal tipped needle on the black wire screw and
tapped my finger on the other and the light lit up slightly for a brief
second before POP! and a puff of smoke.

After I made sure I still had my eye-brows I looked and part of the
screw is melted, the side of the switch is burnt black and my beloved
neon-testers metal tip is melted.

What happen?

Well, I theorized the screw was loose on the side of the switch and
think an arc was created and it was a one time deal.

Well, I was wrong, because in the next two days, all when working on
the same wall in the kitchen (two circuits), I've had three more loud
pops and a quick burst of light when trying to test.

I thought maybe my neon-tester had gone bad, but it even happen with a
new tester.

Any comments/suggestions? I do plan on calling a certified electrician
to come check everything out b/c in my three years of doing electrical
work around the house I've never had this happen. I do though want to
learn what is happening.

Thanks!


Lets see , you connected one end of a neon to a live wire and touched
your finger to the other wire.

I would have thought that makes you the ground wire and you would be
electrocuted .

but thats just me .

I have a multimeter but also bought a non-contact voltage tester . Its
a little pen like device that beeps if the plastic end is near a live
wire.

I did have a similar incident recently , where I was using a multimeter
to check for power at a switch , touched one probe to the screw and
poof , blew the breaker .

It seems it was an old switch with a grounded metal shell and I had
accidently caused the black wire to short to ground .

[what is a S.P. ?] the spark is usually hot to common or hot to
ground. the hot could be returning from a lamp circuit or an
electrified metal outlet.
i'm not an electrician but i used a neon tester exactly as you did for
several years until i needed to chase down odd ac voltages in our 1910
wiring. your neon tester is an old friend, but let's buy a brand new
one to celebrate how it saved your behind. and a new bright headlamp,
digital multimeter, a kitchen GFI, and a GFI tester. hang the old burnt
neon tester up by the main panel to remind you how it saved you. no
more surprises. sparks can be found at old outlets, old switches, old
wire insulation, poor connections, wires improperly crowded into
electrical boxes, loose connections, wire broken free from a wire nut,
reversed polarity, electrified outlet box, defective appliance on the
circuit such as refrigerator, motorized defective appliance leaking
voltage onto wet floor. when you are working in a home where the outlet
is dead and you pulled the main breaker to off or removed the main
cartridge fuse disconnect, you'll still want your electrician holding a
flashlight and cellphone.
brush up on faq at:
http://www.faqs.org/faqs/electrical-wiring/part1/
and you've earned the experience to browse next at wonderful faq for
Sci.Electronics.Repair:
http://www.repairfaq.org/REPAIR/F_Repair.html
test equipment to buy including your good neon tester at:
http://www.repairfaq.org/sam/appfaq.htm#aftesteqp

Native wrote:
Hello,

Installing under cabinet lights and upgrading 30yr old switches and
receptacles in the kitchen when something I've never encountered
happen.

I have a neon-tester I use to make sure there is no power before doing
any work. I'm not sure if this is the official name for it, but it's a
very convenient tool I've had for a couple years now. For example, I
can hold one metal tip to a live black wire and put the other tip to
the neutral white wire and the light at the end of the tester lights
up. Or, if there is not a white neutral wire like a single-pole switch,
I can put the other metal tip on my finger and the light just barely
lights up.

Well, when about to replace a 30 old S.P. by my kitchen sink I went to
check to see if there was power running to the switch. I grabbed my
neon-test, put one metal tipped needle on the black wire screw and
tapped my finger on the other and the light lit up slightly for a brief
second before POP! and a puff of smoke.

After I made sure I still had my eye-brows I looked and part of the
screw is melted, the side of the switch is burnt black and my beloved
neon-testers metal tip is melted.

What happen?

Well, I theorized the screw was loose on the side of the switch and
think an arc was created and it was a one time deal.

Well, I was wrong, because in the next two days, all when working on
the same wall in the kitchen (two circuits), I've had three more loud
pops and a quick burst of light when trying to test.

I thought maybe my neon-tester had gone bad, but it even happen with a
new tester.

Any comments/suggestions? I do plan on calling a certified electrician
to come check everything out b/c in my three years of doing electrical
work around the house I've never had this happen. I do though want to
learn what is happening.

Thanks!

If the switches or outlets are still mounted in the box while you are
testing them, the screw terminals are very close to the metal edge of the
box, which is grounded. If your neon tester probe bridged the gap between
the outlet and the box, you would have exactly as you describe


"Native" wrote in message
ps.com...
Hello,

Installing under cabinet lights and upgrading 30yr old switches and
receptacles in the kitchen when something I've never encountered
happen.

I have a neon-tester I use to make sure there is no power before doing
any work. I'm not sure if this is the official name for it, but it's a
very convenient tool I've had for a couple years now. For example, I
can hold one metal tip to a live black wire and put the other tip to
the neutral white wire and the light at the end of the tester lights
up. Or, if there is not a white neutral wire like a single-pole switch,
I can put the other metal tip on my finger and the light just barely
lights up.

Well, when about to replace a 30 old S.P. by my kitchen sink I went to
check to see if there was power running to the switch. I grabbed my
neon-test, put one metal tipped needle on the black wire screw and
tapped my finger on the other and the light lit up slightly for a brief
second before POP! and a puff of smoke.

After I made sure I still had my eye-brows I looked and part of the
screw is melted, the side of the switch is burnt black and my beloved
neon-testers metal tip is melted.

What happen?

Well, I theorized the screw was loose on the side of the switch and
think an arc was created and it was a one time deal.

Well, I was wrong, because in the next two days, all when working on
the same wall in the kitchen (two circuits), I've had three more loud
pops and a quick burst of light when trying to test.

I thought maybe my neon-tester had gone bad, but it even happen with a
new tester.

Any comments/suggestions? I do plan on calling a certified electrician
to come check everything out b/c in my three years of doing electrical
work around the house I've never had this happen. I do though want to
learn what is happening.

Thanks!

Tex,

If I understand you, you have a single pole switch in your kitchen that
is not connected to the circuit breaker for the kitchen outlets and
repeatedly blows up neon lamp circuit testers. It's time to buy a volt
meter, read the instructions, measure the voltage of each wire to a good
ground, and find the circuit breaker for this switch. Use the main breaker
until you find the breaker for that circuit.
Sorry I'm at a loss as to why a single pole switch would have enough
voltage to blow neon testers. I'd find the breaker at the box and work from
there.

Dave M.

David Martel wrote:
Tex,

If I understand you, you have a single pole switch in your kitchen that
is not connected to the circuit breaker for the kitchen outlets and
repeatedly blows up neon lamp circuit testers. It's time to buy a volt
meter, read the instructions, measure the voltage of each wire to a good
ground, and find the circuit breaker for this switch. Use the main breaker
until you find the breaker for that circuit.
Sorry I'm at a loss as to why a single pole switch would have enough
voltage to blow neon testers. I'd find the breaker at the box and work from
there.

Dave M.


Hmmm,
Some kitchen counter duplex outlets are divided and fed by separate
source. If they are opposite leg, depending on the situation there could
be 240V present. There maybe two breakers involved.
First I'd look at the outlet to see if link between two is missing which
means this is the case.

"Tony Hwang" wrote in message
news:9Fcjh.513955$5R2.410739@pd7urf3no...
David Martel wrote:
Tex,

If I understand you, you have a single pole switch in your kitchen
that is not connected to the circuit breaker for the kitchen outlets and
repeatedly blows up neon lamp circuit testers. It's time to buy a volt
meter, read the instructions, measure the voltage of each wire to a good
ground, and find the circuit breaker for this switch. Use the main
breaker until you find the breaker for that circuit.
Sorry I'm at a loss as to why a single pole switch would have enough
voltage to blow neon testers. I'd find the breaker at the box and work
from there.

Dave M.
Hmmm,
Some kitchen counter duplex outlets are divided and fed by separate
source. If they are opposite leg, depending on the situation there could
be 240V present. There maybe two breakers involved.
First I'd look at the outlet to see if link between two is missing which
means this is the case.

That seems like the most likely explanation. But first I want to know what
a SP is.

On Sat, 23 Dec 2006 16:18:13 GMT, Tony Hwang wrote:

David Martel wrote:
Tex,

If I understand you, you have a single pole switch in your kitchen that
is not connected to the circuit breaker for the kitchen outlets and
repeatedly blows up neon lamp circuit testers. It's time to buy a volt
meter, read the instructions, measure the voltage of each wire to a good
ground, and find the circuit breaker for this switch. Use the main breaker
until you find the breaker for that circuit.
Sorry I'm at a loss as to why a single pole switch would have enough
voltage to blow neon testers. I'd find the breaker at the box and work from
there.

Dave M.


Hmmm,
Some kitchen counter duplex outlets are divided and fed by separate
source. If they are opposite leg, depending on the situation there could
be 240V present. There maybe two breakers involved.
First I'd look at the outlet to see if link between two is missing which
means this is the case.

It doesn't have to. Once side of the outlet could be switched, and on
the same phase (0V between them) as the always-live one. I have seen
such outlets under a sink where the switched side is meant for a
garbage disposal. These may also be found in a living room where the
switched side is meant for lamps.
--
2 days until the winter solstice celebration

Mark Lloyd
http://notstupid.laughingsquid.com

"Never underestimate the power of stupid
people in large groups"

thanks for all the advice and the great link to the FAQ site!

used S.P. for single-pole

On 22 Dec 2006 21:14:33 -0800, "Native"
wrote:

Hello,

Installing under cabinet lights and upgrading 30yr old switches and
receptacles in the kitchen when something I've never encountered
happen.

I have a neon-tester I use to make sure there is no power before doing
any work. I'm not sure if this is the official name for it, but it's a
very convenient tool I've had for a couple years now. For example, I
can hold one metal tip to a live black wire and put the other tip to
the neutral white wire and the light at the end of the tester lights
up. Or, if there is not a white neutral wire like a single-pole switch,
I can put the other metal tip on my finger and the light just barely
lights up.


Not a good idea to put yourself in the circuit.

Well, when about to replace a 30 old S.P. by my kitchen sink I went to
check to see if there was power running to the switch. I grabbed my
neon-test, put one metal tipped needle on the black wire screw and
tapped my finger on the other and the light lit up slightly for a brief
second before POP! and a puff of smoke.

i think you inadvertently shorted to the side of the box. May be
wrong,. but if the tip melted on the tester sounds like thats what
might haev happened. the distance in between the screws and box is
very small and just the width of the test lead could short it out to
the box.

After I made sure I still had my eye-brows I looked and part of the
screw is melted, the side of the switch is burnt black and my beloved
neon-testers metal tip is melted.

Did you see any black stuff on the side of the box?

What happen?

Well, I theorized the screw was loose on the side of the switch and
think an arc was created and it was a one time deal.

Well, I was wrong, because in the next two days, all when working on
the same wall in the kitchen (two circuits), I've had three more loud
pops and a quick burst of light when trying to test.





I thought maybe my neon-tester had gone bad, but it even happen with a
new tester.

Any comments/suggestions? I do plan on calling a certified electrician
to come check everything out b/c in my three years of doing electrical
work around the house I've never had this happen. I do though want to
learn what is happening.

Thanks!

"Mark Lloyd" wrote in message
...
On Sat, 23 Dec 2006 16:18:13 GMT, Tony Hwang wrote:

David Martel wrote:
Tex,

If I understand you, you have a single pole switch in your kitchen
that
is not connected to the circuit breaker for the kitchen outlets and
repeatedly blows up neon lamp circuit testers. It's time to buy a volt
meter, read the instructions, measure the voltage of each wire to a good
ground, and find the circuit breaker for this switch. Use the main
breaker
until you find the breaker for that circuit.
Sorry I'm at a loss as to why a single pole switch would have enough
voltage to blow neon testers. I'd find the breaker at the box and work
from
there.

Dave M.


Hmmm,
Some kitchen counter duplex outlets are divided and fed by separate
source. If they are opposite leg, depending on the situation there could
be 240V present. There maybe two breakers involved.
First I'd look at the outlet to see if link between two is missing which
means this is the case.

It doesn't have to. Once side of the outlet could be switched, and on
the same phase (0V between them) as the always-live one. I have seen
such outlets under a sink where the switched side is meant for a
garbage disposal. These may also be found in a living room where the
switched side is meant for lamps.
--
But then why did his tester go up? Presumably he put it across 240v.

In article , "Toller" wrote:

That seems like the most likely explanation. But first I want to know what
a SP is.

I imagine it means "single pole [switch]".

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

Finding the keyboard operational
Native entered:

Hello,

Installing under cabinet lights and upgrading 30yr old switches and
receptacles in the kitchen when something I've never encountered
happen.

I have a neon-tester I use to make sure there is no power before doing
any work. I'm not sure if this is the official name for it, but it's a
very convenient tool I've had for a couple years now. For example, I
can hold one metal tip to a live black wire and put the other tip to
the neutral white wire and the light at the end of the tester lights
up. Or, if there is not a white neutral wire like a single-pole
switch, I can put the other metal tip on my finger and the light just
barely lights up.

Well, when about to replace a 30 old S.P. by my kitchen sink I went to
check to see if there was power running to the switch. I grabbed my
neon-test, put one metal tipped needle on the black wire screw and
tapped my finger on the other and the light lit up slightly for a
brief second before POP! and a puff of smoke.

After I made sure I still had my eye-brows I looked and part of the
screw is melted, the side of the switch is burnt black and my beloved
neon-testers metal tip is melted.

What happen?

Well, I theorized the screw was loose on the side of the switch and
think an arc was created and it was a one time deal.

Well, I was wrong, because in the next two days, all when working on
the same wall in the kitchen (two circuits), I've had three more loud
pops and a quick burst of light when trying to test.

I thought maybe my neon-tester had gone bad, but it even happen with a
new tester.

Any comments/suggestions? I do plan on calling a certified electrician
to come check everything out b/c in my three years of doing electrical
work around the house I've never had this happen. I do though want to
learn what is happening.

Thanks!

Best guess is that the little metal probe on the hot lead got near a ground
(side of the box) and caused an arc that melted the tip. But 3X?
Do you have a metallic backsplash? We had one made of aluminuim and copper
tiles that gave us an interesting time till we found a loose wire.
I don't know where you picked up the fiinger on the other lead trick but it
worries me a wee bit. It seems to me that you have a current running thru
the current limiting resistor in the tester, the lamp. and then you. It's
kinda like testing 9V batteries with your tounge. Almost all of the time you
won't get hurt.
I am glad that you are getting an electrician in. Let us know what he finds.
Bob
--�
--�
Coffee worth staying up for - NY Times
www.moondoggiecoffee.com

"Toller" wrote in message
...

"Mark Lloyd" wrote in message
...
On Sat, 23 Dec 2006 16:18:13 GMT, Tony Hwang wrote:

David Martel wrote:
Tex,

If I understand you, you have a single pole switch in your kitchen
that
is not connected to the circuit breaker for the kitchen outlets and
repeatedly blows up neon lamp circuit testers. It's time to buy a volt
meter, read the instructions, measure the voltage of each wire to a
good
ground, and find the circuit breaker for this switch. Use the main
breaker
until you find the breaker for that circuit.
Sorry I'm at a loss as to why a single pole switch would have enough
voltage to blow neon testers. I'd find the breaker at the box and work
from
there.

Dave M.


Hmmm,
Some kitchen counter duplex outlets are divided and fed by separate
source. If they are opposite leg, depending on the situation there could
be 240V present. There maybe two breakers involved.
First I'd look at the outlet to see if link between two is missing which
means this is the case.

It doesn't have to. Once side of the outlet could be switched, and on
the same phase (0V between them) as the always-live one. I have seen
such outlets under a sink where the switched side is meant for a
garbage disposal. These may also be found in a living room where the
switched side is meant for lamps.
--
But then why did his tester go up? Presumably he put it across 240v.

Sounds to me like he just shorted one of the probe tips between the hot
terminal and the grounded box, thus destroying the tip. The neon tester will
operate fine on 240 volts.

Don Young

The Other Funk wrote:
I don't know where you picked up the fiinger on the other lead trick but it
worries me a wee bit. It seems to me that you have a current running thru
the current limiting resistor in the tester, the lamp. and then you. It's
kinda like testing 9V batteries with your tounge. Almost all of the time you
won't get hurt.

It's all in the details. When I was young & foolish I won an awful lot
of bets by taping a paperclip on each of two fingers and sticking them
in a hot outlet. The "trick" was wearing rubber soled shoes and
making sure my free hand was in the air. The electricity went between
the 2 fingers (a tingle) and not through my body. (Kids & idiots -
don't try this at home!!!) I suspect the OP may have had a similar
body position.

Bob

wrote:
Native wrote:
Hello,

Installing under cabinet lights and upgrading 30yr old switches and
receptacles in the kitchen when something I've never encountered
happen.

I have a neon-tester I use to make sure there is no power before doing
any work. I'm not sure if this is the official name for it, but it's a
very convenient tool I've had for a couple years now. For example, I
can hold one metal tip to a live black wire and put the other tip to
the neutral white wire and the light at the end of the tester lights
up. Or, if there is not a white neutral wire like a single-pole switch,
I can put the other metal tip on my finger and the light just barely
lights up.

Well, when about to replace a 30 old S.P. by my kitchen sink I went to
check to see if there was power running to the switch. I grabbed my
neon-test, put one metal tipped needle on the black wire screw and
tapped my finger on the other and the light lit up slightly for a brief
second before POP! and a puff of smoke.

After I made sure I still had my eye-brows I looked and part of the
screw is melted, the side of the switch is burnt black and my beloved
neon-testers metal tip is melted.

What happen?

Well, I theorized the screw was loose on the side of the switch and
think an arc was created and it was a one time deal.

Well, I was wrong, because in the next two days, all when working on
the same wall in the kitchen (two circuits), I've had three more loud
pops and a quick burst of light when trying to test.

I thought maybe my neon-tester had gone bad, but it even happen with a
new tester.

Any comments/suggestions? I do plan on calling a certified electrician
to come check everything out b/c in my three years of doing electrical
work around the house I've never had this happen. I do though want to
learn what is happening.

Thanks!


Lets see , you connected one end of a neon to a live wire and touched
your finger to the other wire.

I would have thought that makes you the ground wire and you would be
electrocuted .

but thats just me .

That's not what he said. He said he touched one
lead of the tester to the hot wire and held the
other lead of the tester touching his hand.
That's pretty standard and will light the neon
tube. The NE-2 tube used in the standard tester
requires a very high resistance to keep from
burning out the tube; the include resistor allows
very little current to pass. Pretty much like
lighting a fluorescent tube by holding it close to
a spark plug wire of an operating engine (no shock
there either).



I have a multimeter but also bought a non-contact voltage tester . Its
a little pen like device that beeps if the plastic end is near a live
wire.

I did have a similar incident recently , where I was using a multimeter
to check for power at a switch , touched one probe to the screw and
poof , blew the breaker .

It seems it was an old switch with a grounded metal shell and I had
accidently caused the black wire to short to ground .

Not sure anyone's gotten to the bottom of this. If he's touching 2nd
lead it's still only 110-120 volts. I would always start by testing to
ground, not my bod. Shorting out to the box makes sense, but 3x in a
row? Definitely time to turn off power and check things out.

Yeah, but we want to know if it was SPST or SPDT. (I know; I'm
being a wiseacre.)

--

Christopher A. Young
You can't shout down a troll.
You have to starve them.
..

"Doug Miller" wrote in message
. net...
In article , "Toller"
wrote:

That seems like the most likely explanation. But first I want
to know what
a SP is.

I imagine it means "single pole [switch]".

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

Thanks for everyones help. Had an electrician come out and here is the
conclusion. The sparks I saw with my neon-tester were due to the
switches being back-stabbed and the screw on the side was loose. When
my neon-tester probe touched the side (which was grounded) it appears
(based off where the probe and screw melted) it brushed against the
loose screw and then sparked. This appears to be the case with both
switches.

Needless to say, he also recommended to get a digitial multimeter which
I did and I love it. It was great to have him say that b/c it helped
ease the price with the wife!

Thanks again to everyone's help!