I did a Google search of web pages and newsgroups and came up with a
couple of threads, one about light bulbs around the house often
burning out and one about oven lights burning out. Both threads
suggested checking to make sure an impedance problem with the neutral
line wasn't causing an imbalance in the voltage on either side of the
neutral. Apparently, the symptom,would be a high voltage reading in
the socket.
I checked the voltage in one of the kitchen sockets and it read
118.2V. I then put one lead of the voltmeter on the copper center
contact of the oven light socket and the other lead on the threaded
part of the socket and read the same 118.2V.
As an experiment, I left one appliance bulb on for about 8 hours and
it survived and I turned off the light. But the next day when I opened
the oven door the bulb flashed and failed. I also tried a cheap 40W
regular bulb, which survived baking something in the oven but burned
out after a few hours when I experimentally left it on after I was
finished baking. That experiment was probably flawed though, maybe
regular bulbs don't survive baking.
I've tried GE, Philips and Home Depot appliance bulbs.
I partially pulled out the oven and could see where the oven was
connected to the house wiring. From what I could see, the wires were
connected with twist connectors and then the bottom of the connector
was wrapped in electrical tape.
The only thing I can think of is maybe the door and light switch are
corroded and when they make contact, they're making a bunch of
interrmittent contacts, cycling the bulb many times before a good
contact is made. That would effectively put the bulb through dozens
or hundreds of power cycles. That might burn out a bulb quickly and
explain why the bulbs haven't failed when I left them on for hours at
a time.
Does anyone have any experience with this kind of problem?
I'm not an electrician but is there anything else I can try to see
what the problem is?
Thanks.
My guess is it is electric, which means it is bringing in 240 V.
Further I am guessing that when you shut the oven door it is causing a short
to 240 or an opening of the neutral also causing 240V and a flash ending of
your lamp.
Clearly I am guessing, but if I am right, I would worry about more than
just oven lights, I would worry about frying the cook.
If it is gas, that blows my theory.
--
Joseph E. Meehan
26 + 6 = 1 It's Irish Math
<webl...@nomail.com> wrote in message
news:mf8r2vcnomieec9l2...@4ax.com...
AFAIK, the only connection the door has to 240V would be through the
light switch the closes when the door is closed.
Wouldn't a short to 240V cause the breaker to open?
--
Joseph E. Meehan
26 + 6 = 1 It's Irish Math
<webl...@nomail.com> wrote in message
news:27ir2v8mqq78qmcnt...@4ax.com...
> Ack, I gave all the details but the most obvious. Yes, it's an
> electric oven.
>
> AFAIK, the only connection the door has to 240V would be through the
> light switch the closes when the door is closed.
>
> Wouldn't a short to 240V cause the breaker to open?
I was thinking of a short to 240V not accross 240. It could be the
switch somehow, I will have to think about that one, or it could be a loose
wire that is being pushed against another somehow.
--
Joseph E. Meehan
26 + 6 = 1 It's Irish Math
<webl...@nomail.com> wrote in message
news:27ir2v8mqq78qmcnt...@4ax.com...
Thanks for the reply.
Out of curiosity, what is it about poor contact among the wires that
causes the bulb to burn out? I know (as a somewhat unrelated example)
that the high voltage wires in a car ingnition system can break down,
reducing voltage and causing the spark plugs to misfire.
Does poor contact between the internal wiring and the socket cause a
similar low voltage situation? Or is arcing occuring, which is
damaging the bulb?
Also, is there anything I should specifically look or test for when I
have the oven out? Is there a way to tell if the wire or socket is at
fault?
A poor contact causes heat. The heat is transferred to the bulb's filament
shortening its life. I would think in that case it is just coincidence that
it failed when initially energized or the filament weakened when it cooled
and just 'gave up the ghost' when powered again.
>Also, is there anything I should specifically look or test for when I
>have the oven out? Is there a way to tell if the wire or socket is at
>fault?
Discoloration would be the most likely sign although it may not always be
visible.
If it is a self cleaning range, some appliance manufacturers sell a bulb
specifically designed (so they say) for that application. Check local
*appliance parts* suppliers. You might also want to consider a replacement
bulb with a brass base in place of aluminum if the socket is brass as well.
Jenn Air ranges had a problem years ago when using a aluminum base bulbs in
their brass sockets.
Dan O.
-
Appliance411.com
http://ng.Appliance411.com/?ref411=+GE+range
=Ð~~~~~~
??? The filament must already be burning in the range of 3000 degrees
C to 5000 degrees C. Check out this out this web site:
http://invsee.asu.edu/nmodules/lightbulbmod/filament.html
The heat generated by a poor contact can't be any appreciable fraction
of the normal temperature of a lamp filament, if it was 20% of 3000
degrees there would be a fire, or the wire would melt.
--
Joseph E. Meehan
26 + 6 = 1 It's Irish Math
<webl...@nomail.com> wrote in message
news:ni2u2vcnjh53vs7cs...@4ax.com...
Thanks for the reply. You must have missed my original post. I've
repeated it below. I don't think there's a problem with the neutral
connection because I measured the voltage at the socket at it was the
same as one of the kitchen sockets, 118.2V.
...............
Hello all. I have a 12 year old GE built-in oven and over the past
--
Joseph E. Meehan
26 + 6 = 1 It's Irish Math
<webl...@nomail.com> wrote in message
news:89pu2votcpidg8fn5...@4ax.com...
I don't understand. I measured the voltage across the socket and it
was 118.2V. If the bulb were burning out because of a poor connection
to the neutral that resulted in high voltage, wouldn't I be able to
measure that higher voltage?
If the connection has 2K ohms and your meter has 2M ohms the full
voltage will be read. However if your meter has 2K and the connection has
2M then it will show a real voltage drop. Today's digital meters have very
high internal resistance so they then to miss some of the things the older
meters would pick up.
--
Joseph E. Meehan
26 + 6 = 1 It's Irish Math
<webl...@nomail.com> wrote in message
news:d6403v00td3ecrli6...@4ax.com...
>I don't understand. I measured the voltage across the socket and it
>was 118.2V. If the bulb were burning out because of a poor connection
>to the neutral that resulted in high voltage, wouldn't I be able to
>measure that higher voltage?
Not necessarily. Your meter puts no load on the connections. If you
have a poor connection on the neutral somewhere it might not show up
until it was under load (the bulb is on).
Steve