Carl Finch on tue 29 apr 03
At 09:03 PM 4/29/03 -0600, John Rodgers wrote:
>Lisa, that WAS scarey no doubt.!!!
>
>I have wired a lot of kilns. Your experience is one reason I NEVER EVER
>hardwire a kiln. I want to be able to physically disconnect the thing by
>unplugging that sucker so I can see for myself from the kiln that the
>power is disconnected.
The useful thing (which would have prevented both Lisa's scare and John's)
is to do what careful experienced electricians do:
(1) Turn off (what purports to be) the power.
(2) Check at the appliance/receptacle/etc. to ensure that the power really
is off.
(3) Ascertain that your checking device is still working!
One never knows WHAT the person who wired the house/studio/etc. was
thinking (or drinking?). Even experienced electricians make mistakes.
There are several way to check that the power is off. For a receptacle,
plug in a working lamp (if it's a duplex receptacle, plug the lamp into
BOTH outlets--they might be separately powered). Then take the lamp back
to its ORIGINAL place and check to make sure it still works (the filament
might just have chosen this moment to break!).
There are multimeters and inexpensive circuit testers widely
available. But if you are not comfortable in using these, it's time to get
knowledgeable help.
Since I wired my workshop last January I've been reading the
alt.home.repair news group. The variety of dreadful and terribly dangerous
wiring mistakes folks there have encountered (or attempted) makes for
interestin' reading.
I strongly suspect that the guy who put in Lisa's 240v circuits was in
violation of the code (NEC)--I would certainly think that a "Main" breaker
in a panel or subpanel ought to disconnect ALL other circuits leaving that
panel.
Regarding your, "one reason I NEVER EVER hardwire a kiln. I want to be able
to physically disconnect the thing by
unplugging," although my kiln is currently plugged into a receptacle, once
I decide where I really want it I intend to hard wire it. I have a small
sub-panel box containing a 60amp breaker just a few feet from the kiln--it
is basically just a disconnect for the kiln. In an emergency i believe it
will be easier and quicker to flip that switch (breaker) off rather than to
have to grope for the kiln plug and try to wrench it from the wall!
--Carl
in Medford, Oregon
Tony Ferguson on tue 29 apr 03
Lisa, you have redefined the meaning of "being grounded."
Tony Ferguson
----- Original Message -----
From: "L. P. Skeen"
To:
Sent: Tuesday, April 29, 2003 9:09 PM
Subject: Re: Learn from my $200 mistake
> hehhehheh.....nope, no multimeters for me. Here's why: One, I swore
never
> to mess with electricity again. Two, every multimeter I've ever seen
EXCEPT
> the one my next door neighbor the electrician uses reads wrong and
indicates
> dead elements when they're really alive.
>
> L
> ----- Original Message -----
> From: "Rod Wuetherick"
> > Your neighbor may have mentioned a multi-meter. These are indispensable
to
> > have around in a studio. They are great for checking if plus work,
> > continuity of elements, etc.
>
>
____________________________________________________________________________
__
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.
>
L. P. Skeen on tue 29 apr 03
Thanks John. Actually, I asked the installation guy to leave the plug on
the kiln, but he hardwired it anyway. :( He claims the electrical inspector
would be happier w/ hardwiring than w/ a plug.
L
----- Original Message -----
From: "John Rodgers"
> I have wired a lot of kilns. Your experience is one reason I NEVER EVER
> hardwire a kiln. I want to be able to physically disconnect the thing by
> unplugging that sucker so I can see for myself from the kiln that the
> power is disconnected.
> Lisa, Glad you are OK!!
>
L. P. Skeen on tue 29 apr 03
Well, I just about killed myself on Sunday - literally.
You may recall seeing my plea for information re: my Olympic Oval kiln =
w/ Bartlett controller which I sent on Saturday. The last firing I did =
in the kiln was ^6 glaze firing. The glazes looked great as usual, but =
the controller said FAIL where it should have read the internal =
temperature of the kiln. I was stumped, having never heard of such a =
thing before, so I wrote Clayart for help. 2 people sent suggestions =
and archive references offlist.
One of the archive references was for Arnold Howard's instructions on =
the Paperclip Test for thermocouples. This involves removing the =
thermocouple and placing a U-shaped section of paperclip in the slots =
where the wires came out. If the readout shows room temperature, you =
need a new thermocouple, which costs about $40.
I printed out the instructions, got myself a jumbo paperclip, and headed =
off to the studio. Before I ever went in the building, I walked around =
back and flipped off the breaker labeled "MAIN BREAKER GARAGE AREA", =
which should have turned off all the electricity to the side of the =
building where the kiln is located. (My kiln is hardwired instead of =
plugged into the wall.) Went inside, got out my wire cutters and =
screwdriver, and sat down in a metal folding chair to remove the =
computer face from the control box.
I had the screws out and the face pulled about 1/4" when there was an =
explosion like a gunshot and sparks flying everywhere. I personally =
flipped backwards over the chair and landed on my shoulder in the =
concrete floor. (Damn good thing I wasn't wearing my prom dress, no?) =
I did NOT get shocked, but the sound and sparks scared the bejesus out =
of me; I THOUGHT I'd turned off the electricity.
Turns out the guy who ran the 200 amp service in here put each kiln =
outlet on its own separate breaker, unrelated to the ones marked MAIN, =
and he didn't label the damn things. :( My next door neighbor the =
electrical contractor has made me swear never to try anything electrical =
ever again (NOT a problem!), and a replacement computer cost $165 from =
Bartlett, which I could have saved if I had flipped off the right =
switch. He said 240v is definitely enough to kill me - but the kiln was =
a better "ground" than I was, so that's why I din't get shocked.
Have been reading folktales to my ESOL kids the last couple of weeks, =
and as you may know, Folktales always have a moral. This tale is no =
different. The moral of this story is twofold: Be damn sure the =
electricity is turned OFF before you mess with a kiln controller, and if =
you don't know anything about electrical stuff, call somebody who does.
L
L. P. Skeen www.living-tree.net
Living Tree Pottery, Summerfield, NC
Get your copy of the 2003 Clay Lover's Calendar
at my website above! :)
Rod Wuetherick on tue 29 apr 03
Lisa,
Your neighbor may have mentioned a multi-meter. These are indispensable to
have around in a studio. They are great for checking if plus work,
continuity of elements, etc. I think that you can test your problem by
checking the continuity. This is a far wiser way to go as you will never
have contact with anything electrical. You use plastic\rubber shielded
probes or alligator clips.
Anytime anyone tells you to check something electrical with a paper clip.
Think before you go ahead, is there a safer way to do this? Cheap
multi-meters can be had here in Canada sometimes for as little as $9.99
Cheers
> One of the archive references was for Arnold Howard's
> instructions on the Paperclip Test for thermocouples. This
> involves removing the thermocouple and placing a U-shaped section
> of paperclip in the slots where the wires came out. If the
> readout shows room temperature, you need a new thermocouple,
> which costs about $40.
>
John Rodgers on tue 29 apr 03
Lisa, that WAS scarey no doubt.!!!
I have wired a lot of kilns. Your experience is one reason I NEVER EVER
hardwire a kiln. I want to be able to physically disconnect the thing by
unplugging that sucker so I can see for myself from the kiln that the
power is disconnected.
I had a similar experience as yours, but not on a kiln, and not with all
the fireworks. My case was in the repair of my neighbors
Airconditioner. A blade on the cooling fan had come loose so I
volunteered to replace the fan. it necessitated disconnecting some wires
in a box on the unit. The unit was hardwired to it's own fuse box and
there was a pull handle on the side. Push it up and power was off, pull
it down and power was on. Electrical code called for that fuse box and
the hard wire connection within 5 feet of the airconditioner. Being
safety minded I told my neighbor to turn the thermostat off, then I did
the thing and pushed the fuse box handle up shutting off the power. I
then took the cover off the box on the side of the unit, stuck my
screwdriver in there and disconnected some things and shortly had the
cover off the air conditioner, the fan blade installed, and the whole
thing back together. I shouted at my neighbor to turn on the thermostat
and set it for cooling, that I would then turn on the power. Before I
could throw the switch, the moment the thermostat called for cooling,
that stupid airconditioner turned on!! I'm standing there astounded,
frozen to the spot looking at that supid machine running and the pull
handle still up in the shut-off position. I reached over and cycled the
handle several times. Air conditioner continued to run, never waivered.
I opened the fuse panel and guess what??? No fuses. Some fool had hard
wired that air conditionaer across the back of the fuse box and the box
simply served as a connector. Nothing more. There was absolutely not
safety, and no protections. I was working on a 240 Volt 60 Amp Circuit
and could have been fried. Don't know why I wasn't. Just the way I
handled that screwdriver is what saved my butt!!! I have been very wary
of electrical stuff where I can't see the mechanical disconnect in
action.!~!
Lisa, Glad you are OK!!
John Rodgers
Birmingham, AL
L. P. Skeen wrote:
>Well, I just about killed myself on Sunday - literally.
>
>You may recall seeing my plea for information re: my Olympic Oval kiln w/ Bartlett controller which I sent on Saturday. The last firing I did in the kiln was ^6 glaze firing. The glazes looked great as usual, but the controller said FAIL where it should have read the internal temperature of the kiln. I was stumped, having never heard of such a thing before, so I wrote Clayart for help. 2 people sent suggestions and archive references offlist.
>
>One of the archive references was for Arnold Howard's instructions on the Paperclip Test for thermocouples. This involves removing the thermocouple and placing a U-shaped section of paperclip in the slots where the wires came out. If the readout shows room temperature, you need a new thermocouple, which costs about $40.
>
>I printed out the instructions, got myself a jumbo paperclip, and headed off to the studio. Before I ever went in the building, I walked around back and flipped off the breaker labeled "MAIN BREAKER GARAGE AREA", which should have turned off all the electricity to the side of the building where the kiln is located. (My kiln is hardwired instead of plugged into the wall.) Went inside, got out my wire cutters and screwdriver, and sat down in a metal folding chair to remove the computer face from the control box.
>
>I had the screws out and the face pulled about 1/4" when there was an explosion like a gunshot and sparks flying everywhere. I personally flipped backwards over the chair and landed on my shoulder in the concrete floor. (Damn good thing I wasn't wearing my prom dress, no?) I did NOT get shocked, but the sound and sparks scared the bejesus out of me; I THOUGHT I'd turned off the electricity.
>
>Turns out the guy who ran the 200 amp service in here put each kiln outlet on its own separate breaker, unrelated to the ones marked MAIN, and he didn't label the damn things. :( My next door neighbor the electrical contractor has made me swear never to try anything electrical ever again (NOT a problem!), and a replacement computer cost $165 from Bartlett, which I could have saved if I had flipped off the right switch. He said 240v is definitely enough to kill me - but the kiln was a better "ground" than I was, so that's why I din't get shocked.
>
>Have been reading folktales to my ESOL kids the last couple of weeks, and as you may know, Folktales always have a moral. This tale is no different. The moral of this story is twofold: Be damn sure the electricity is turned OFF before you mess with a kiln controller, and if you don't know anything about electrical stuff, call somebody who does.
>
>L
>
>
>
>L. P. Skeen www.living-tree.net
>Living Tree Pottery, Summerfield, NC
>Get your copy of the 2003 Clay Lover's Calendar
>at my website above! :)
>
>______________________________________________________________________________
>Send postings to clayart@lsv.ceramics.org
>
>You may look at the archives for the list or change your subscription
>settings from http://www.ceramics.org/clayart/
>
>Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
>
>
>
L. P. Skeen on tue 29 apr 03
hehhehheh.....nope, no multimeters for me. Here's why: One, I swore never
to mess with electricity again. Two, every multimeter I've ever seen EXCEPT
the one my next door neighbor the electrician uses reads wrong and indicates
dead elements when they're really alive.
L
----- Original Message -----
From: "Rod Wuetherick"
> Your neighbor may have mentioned a multi-meter. These are indispensable to
> have around in a studio. They are great for checking if plus work,
> continuity of elements, etc.
Cindi Anderson on wed 30 apr 03
But you have no choice over 48 amps, so I assume you stick to smaller kilns?
Cindi
----- Original Message -----
From: "John Rodgers"
> I have wired a lot of kilns. Your experience is one reason I NEVER EVER
> hardwire a kiln. I want to be able to physically disconnect the thing by
> unplugging that sucker so I can see for myself from the kiln that the
> power is disconnected.
Carl Finch on wed 30 apr 03
At 11:15 PM 4/29/03 -0400, L. P. Skeen wrote:
>Actually, I asked the installation guy to leave the plug on
>the kiln, but he hardwired it anyway. :(
So are you saying that the only way to disconnect the kiln is to throw the
breaker? If true, that breaker panel should be very close to the kiln
itself--like not much more than arm's length. If you have to run outside
to reach the breaker panel to disconnect, that's too far.
>He claims the electrical inspector
>would be happier w/ hardwiring than w/ a plug.
Seems likely, although mine was happy enough with my receptacle/plug
arrangement. But I have a separate disconnect switch (an additional
breaker, actually--cheaper than a switch) just a couple feet from the
kiln. But I must say that his "inspection" of my amateur wiring job was
rather intuitive--he never even ventured upstairs in my
workshop. I'm guessing my wiring looked pretty neat and that he had a lot
of inspections to make that day!
Your LOCAL inspector is always the final arbiter of the code. The whole
purpose of the code is safety. A "pass" from a half-hearted inspection
could miss a lot!
--Carl
Kenneth D. Westfall on wed 30 apr 03
Multi test meters are a great asset for testing kiln element and electrical
circuits. The only draw back is you have to get to bare wires to do the
test. Bare wires means risk of getting shocked! A additional little tool
is a current sensing pen. They sense electrical current with out touching
bare wires. Fluke and several other company's make them and there fairly
cheep. Fieldpiece also makes a good test meter, Vole, amp probe, currant
probe all in one if you want just one multi-test meter. Any good electrical
contractors supply house and maybe even WW Graingers carry them. As with
anything you have to test the pen with a known live circuit before moving
on to the unknown.
Kenneth D. Westfall
Pine Hill Pottery
R.D. #2 Box 6AA
Harrisville, WV 26362
pinehill@ruralnet.org
http://www.pinehillpottery.com
L. P. Skeen on wed 30 apr 03
> So are you saying that the only way to disconnect the kiln is to throw the
> breaker? If true, that breaker panel should be very close to the kiln
> itself--like not much more than arm's length. If you have to run outside
> to reach the breaker panel to disconnect, that's too far.
Yup, tha'd be exactly what I'm saying. I don't like it either, but it's
done and I'm NOT about to undo it.
L
L. P. Skeen on wed 30 apr 03
Hey Tony, redefining EVERYTHING is my middle name..........
----- Original Message -----
From: "Tony Ferguson"
> Lisa, you have redefined the meaning of "being grounded."
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