Gerry Turner on wed 22 mar 00
------------------
Oh boy, do I need help=21 In the first place I live kind of out in the =
woods sort
of under a rock with no kiln gurus anywhere near.....or far either so far as=
I
know. About a year ago one of the switches on my Duncan 1029 kiln blew
up.......literally. Sparks, smoke, the whole pyrotechnic display. Right in=
the
middle of a firing for no reason that I understand even now. So I replaced =
the
switch (infinite type) and various lead wires that melted and singed in the
process. Also changed the circuit breaker from a 45 amp. to a 60 amp. at
someone's suggestion. The kiln is about 25 feet from the breaker panel and =
is
wired directly. I also replaced the block that controls the kiln setter. =
But
the kiln has never been the same. It had been taking longer and longer to =
fire
and finally wouldn't go anywhere. Guess what......another switch burned =
out.
So that is replaced. Continuity on all the elements checks out. All three
banks of elements get some heat but not more than maybe 500 degrees. A =
friend
suggested maybe the circuit breaker was faulty and it seemed to be.........I
couldn't get a reading with a neon light tester on one side of the breaker, =
so I
got a new breaker, 50 amp. 'cuz that's all they have in my metropolis of =
1100
souls, and installed it. Turned on the kiln.......empty because I don't =
want
to keep loading and unloading........but after 6 hours on high nothing =
happened
except that it warmed up, sort of. What am I doing wrong? Is there =
something
in that kiln sitter that I'm overlooking? I don't understand why two =
switches
have burned out in a kiln that has not been fired more than 50 or 60
times...........albeit over fired to cone 8+ two or three times. Do you =
think I
should bypass the kiln sitter? Where else can I look? (I know, everybody =
is
thinking about leaving or has left for NCECA, but I'm home alone and =
climbing
the walls. Help?)
Gerry in Wisconsin where the ice went out a month early but the birds are =
still
flocking to the feeder even though the sandhills are dancing across the =
valley.
Brad Sondahl on thu 23 mar 00
When troubleshooting electric kilns, consider anything that happened,
and anything you've done. In this instance you replaced the breaker,
and there could be a bad connection at the breaker, or it could have got
reconnected as 110v (unlikely). Test for 220v at the kiln.
When switches die, which really is fairly common, they can arc and
create a mess as you describe. It doesn't reflect on what caused it.
Infinite switches are constantly popping on and off, and don't last as
long as 3 position ones, and can't bear as high load either. It is
possible that the arcing damaged the lead wires to the element so that
they need to be totally replaced. Can you check for 220 volts on the
switch itself.
As to checking elements, continuity is good, physical inspection is
better, because a section could be fused and passing electricity but
pretty shot. When the kiln is not on, you can run a screwdriver along
the course of each element, and you'll notice if there is a gap.
50-60 firings is about average for element length, although they should
go longer if you're firing at midrange temperatures.
Kiln sitters (mechanical ones) are on or off affairs, so it's not likely
to be the source of the problem, unless it's electronic and kinky.
So check for electricity at all accessible points--starting at the
switches and working back through the kiln if necessary. If all the
elements aren't firing, suspect the supply of electricity coming into
the kilnsitter, switches, etc.
Hope this helps
--
Brad Sondahl
New commercial pottery page http://sondahl.safeshopper.com
http://www.camasnet.com/~asondahl/bradindex.html
Sondahl homepage http://www.camasnet.com/~asondahl
Original literature, music, pottery, and art
Ray Aldridge on fri 24 mar 00
At 06:11 PM 3/23/00 EST, you wrote:
>----------------------------Original message----------------------------
>When troubleshooting electric kilns, consider anything that happened,
>and anything you've done.
(snipped very good advice)
>
>Kiln sitters (mechanical ones) are on or off affairs, so it's not likely
>to be the source of the problem, unless it's electronic and kinky.
Just a data point-- I had trouble with one of the contact surfaces on one
old kilnsitter-- one of the element circuits failed in midfiring, and since
the elements were almost new, I looked elsewhere. When I took the
kilnsitter apart, one of the contact leaves was so badly pitted from arcing
that it was no longer working. I sanded down both sides of the contact,
and it started working again, but eventually I'll have to replace the
contact, which is not very expensive.
Ray
Aldridge Porcelain and Stoneware
http://www.goodpots.com
Pennie/Jim on fri 19 jul 02
My old electric kiln is drawing twice as many amps as it should. What is
the
problem? The kiln works just blows the breaker when I bisque pot. Any
advice
would be appreciated,
thanks. Pennie
>
>
____________________________________________________________________________
__
> Send postings to clayart@lsv.ceramics.org
>
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>
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melpots@pclink.com.
Wyndham Dennison on mon 21 apr 08
>
> will get to good wiring on the cord. It doesn't look that badly damaged. Of course the plug and
> receptacle are history. This kiln has been plugged in to the same circuit for a good ten years and
> has done many firings, mostly to cone 04 and 06. The plug has never even gotten hot before this.
> The wire run from the main box is about 3 feet
Laurie, This is a common problem with electric kilns I have used. I'm
surprised that this has not happened earlier. The electricity surging
through the line heats & expands the plugs then cools and contracts. At
some point some arcing occurs and more heating at the plug til either a
short or other failure occurs. This can also happen at your relays in
the kiln controller or in the connection to the elements and one can
lead to the others problem resulting sometimes of several problem
cascading at once. Electricity can be thought of as a hammer hitting
each time the controller turns on. In a digital controller this may
happen hundreds of times a firing. A breaker may also be less than
optimal after 10 yrs of service and at the small cost of a breaker, it
might be wise to replace it when the plug is replaced. The cord may have
been weakened further back than it appears, as copper can oxidize from
the heat and become a problem.
I have had these same problems on several kiln and have found out it was
cheaper to replace the breaker, the wire and the plug as well as check
the condition of the relays in the controller, than to just replace the
plug. This maybe over kill but maybe not.
I hope this helps, I sure others here have had some of the same problems
as well. Wyndham
David Martin Hershey on thu 11 sep 08
Hi Steve, (Monica?)
The last time I looked, 60 amp breakers were not cheap...
It's possible that a connection to the breaker has become loose, and
it's causing the breaker to overheat and trip. I had this happen with a
100 amp sub-panel main breaker once.
If you feel confident that you can do the job safely, turn off the power
to the sub-panel from the main panel. . Take the cover off the panel and
double check that the panel is dead. Check the connections to the
breaker. If either is not very tight, that's likely the problem. Look
for evidence of corrosion or arching, and clean the ends of the wire if
necessary. Tighten the wires REALLY tight, using the appropriate tool.
Or you could call the electrician in just to check the breaker stuff for
you.
Another common possibility is that if the kiln is not hard wired in, the
wall plug or cord is corroding or going bad, causing the breaker to
overheat. This would be a very serious condition. Unplug the kiln, and
check the condition of the plug. Any corrosion? Look for evidence of
corrosion or burn marks in the receptacle slots.
Feel the cord/plug/receptacle when the kiln is running up. If it's too
hot to hold your hand on, you need to replace one or both ASAP. The
electrician could also check inside the receptacle box for you. You may
see evidence of overheating, like the receptacle or wire insulation
melting...
Best, DMH
David Martin Hershey
DMH Studio + Design
2629 Manhattan Ave #137
Hermosa Beach CA USA
90254-2447 310.379.6890
http://www.dmhstudio.com/
Carl Finch wrote:
> At 04:31 AM 9/11/2008, Monica Wright (sometimes known as "Steve") wrote:
>
>> OK, I need some ideas here. At school I have an AIM 2327 kiln, 48.6
>> amps. Whenever all the switches (6 of them) get turned up to around
>> 7 (out of 10) the breaker gets thrown and of course I get extremely
>> angry. There is just starting to get some color in the kiln when it
>> happens so I am guessing between 1200-1300 degrees. It is on a 60
>> amp breaker so that should not be the problem.
>
> They do wear out! After about 10 years the breaker that served my
> microwave oven started popping open occasionally when the oven
> started up (heaviest current draw). New breaker solved it. They're
> cheap!
>
Monica Wright on thu 11 sep 08
OK, I need some ideas here.=A0 At school I have an AIM 2327 kiln, 48.6 amps=
.=A0 Whenever all the switches (6 of them) get turned up to around 7 (out o=
f 10) the breaker gets thrown and of course I get extremely angry.=A0 There=
is just starting to get some color in the kiln when it happens so I am gue=
ssing between 1200-1300 degrees.=A0 It is on a 60 amp breaker so that shoul=
d not be the problem.=A0 The guy I have coming to look at it may not be abl=
e to make it for quite a while and I don't like waiting.=A0 Most electricia=
ns just stare and scratch their head when the see a kiln so I am slow at ca=
lling the local electrician.=A0 I figured that if I had some ideas on what =
the problem=A0could be=A0I might be able share them with the electrician if=
I do call him.
=A0
The elements look good.=A0 Some of the top brick are busted up (last art te=
acher was an idiot) and the element is sagging a little but I've seen a lot=
worse.=A0 The kiln is about 8 years old.=A0 Probably fired 100-150 times t=
o cone 04.
=A0
Any ideas?
=A0
-Steve
Carl Finch on thu 11 sep 08
At 04:31 AM 9/11/2008, Monica Wright (sometimes known as "Steve") wrote:
>OK, I need some ideas here. At school I have an AIM 2327 kiln, 48.6
>amps. Whenever all the switches (6 of them) get turned up to around
>7 (out of 10) the breaker gets thrown and of course I get extremely
>angry. There is just starting to get some color in the kiln when it
>happens so I am guessing between 1200-1300 degrees. It is on a 60
>amp breaker so that should not be the problem.
They do wear out! After about 10 years the breaker that served my
microwave oven started popping open occasionally when the oven
started up (heaviest current draw). New breaker solved it. They're cheap!
--Carl
in Medford, Oregon
Carl Finch on fri 12 sep 08
At 09:48 PM 9/11/2008, David Martin Hershey wrote:
>The last time I looked, 60 amp breakers were not cheap...
That depends! I just checked and see I paid $15.82 for mine
(granted, that was 5 years ago), but now see some on the Internet for
little as $14. Compared to all the other stuff I had to buy to wire
my shop, that WAS cheap!
But one can't really price-shop for a replacement breaker. They must
fit the panel (breaker box) and different manufacturers apparently
build their panels to different dimensions. So one may be stuck with
having to spend quite a bit more for one that fits! (I also saw some
60 amp breakers on the same web site in the $60 range!)
--Carl
in Medford, Oregon
Monica Wright on fri 12 sep 08
Yeah, the only way I know how to check the stuff you mentioned would be by =
peeing on the breaker box.=A0 I think I'll call the electrician on that one=
.=A0 I tried to work on a kiln a couple years ago and the administration ha=
d a fit.=A0 Of course the electrician they called screwed everything up any=
way.=A0 But that is another topic entirely.
=A0
The kiln is hard wired.=A0 No plug.
=A0
-Steve (not Monica)
--- On Thu, 9/11/08, David Martin Hershey wrote:
From: David Martin Hershey
Subject: Re: electric kiln problem
To: CLAYART@LSV.CERAMICS.ORG
Date: Thursday, September 11, 2008, 11:48 PM
Hi Steve, (Monica?)
The last time I looked, 60 amp breakers were not cheap...
It's possible that a connection to the breaker has become loose, and
it's causing the breaker to overheat and trip. I had this happen with a
100 amp sub-panel main breaker once.
If you feel confident that you can do the job safely, turn off the power
to the sub-panel from the main panel. . Take the cover off the panel and
double check that the panel is dead. Check the connections to the
breaker. If either is not very tight, that's likely the problem. Look
for evidence of corrosion or arching, and clean the ends of the wire if
necessary. Tighten the wires REALLY tight, using the appropriate tool.
Or you could call the electrician in just to check the breaker stuff for
you.
Another common possibility is that if the kiln is not hard wired in, the
wall plug or cord is corroding or going bad, causing the breaker to
overheat. This would be a very serious condition. Unplug the kiln, and
check the condition of the plug. Any corrosion? Look for evidence of
corrosion or burn marks in the receptacle slots.
Feel the cord/plug/receptacle when the kiln is running up. If it's too
hot to hold your hand on, you need to replace one or both ASAP. The
electrician could also check inside the receptacle box for you. You may
see evidence of overheating, like the receptacle or wire insulation
melting...
Best, DMH
David Martin Hershey
DMH Studio + Design
2629 Manhattan Ave #137
Hermosa Beach CA USA
90254-2447 310.379.6890
http://www.dmhstudio.com/
Carl Finch wrote:
> At 04:31 AM 9/11/2008, Monica Wright (sometimes known as
"Steve") wrote:
>
>> OK, I need some ideas here. At school I have an AIM 2327 kiln, 48.6
>> amps. Whenever all the switches (6 of them) get turned up to around
>> 7 (out of 10) the breaker gets thrown and of course I get extremely
>> angry. There is just starting to get some color in the kiln when it
>> happens so I am guessing between 1200-1300 degrees. It is on a 60
>> amp breaker so that should not be the problem.
>
> They do wear out! After about 10 years the breaker that served my
> microwave oven started popping open occasionally when the oven
> started up (heaviest current draw). New breaker solved it. They're
> cheap!
>
Arnold Howard on mon 15 sep 08
Click here for an article on counterfeit electric breakers
and extension cords:
http://www.reuters.com/article/pressRelease/idUS150325+23-Jun-2008+PRN20080623
This is something to be aware of if you find breakers at
bargain prices.
Sincerely,
Arnold Howard
Paragon Industries, L.P., Mesquite, Texas USA
ahoward@paragonweb.com / www.paragonweb.com
Kristin Schoonover on sat 10 mar 12
I have an electric kiln that I have fired for 10 years. I fire to cone 6=
=3D
. I mainly=3D20
used a copper glaze, when I say mainly, I mean majorly, and I think the=3D2=
0=3D
copper has absorbed into the kiln brick. Now when I glaze fire, the copp=
=3D
er is=3D20
coming out and tinting the other lighter, a yellow and clear glaze, green=
=3D
. Has=3D20
anyone ever heard of this, or know something i can do to get the copper o=
=3D
ut.
Ben Morrison on sat 10 mar 12
I've seen this before quite a lot. Mostly I've seen pink and =3D
Kristin,=3D0A=3D0AI've seen this before quite a lot. Mostly I've seen pink =
and =3D
green blushing in reduction kilns from heavy copper glaze use. I believe th=
=3D
is kiln can either be continually fired with copper ware and black glazes, =
=3D
or you can replace all the bricks. In my mind if the bricks are still in go=
=3D
od condition besides the copper contamination it would make more sense to p=
=3D
urchase a second kiln and don't fire your copper or chrome ware in the new =
=3D
kiln, only in the old kiln. That way you actually solve the problem long te=
=3D
rm instead of a temporary fix.=3D0A=3D0ABest of luck,=3D0ABen=3D0A=3D0A____=
__________=3D
__________________=3D0A From: Kristin Schoonover =3D=
0ATo=3D
: Clayart@LSV.CERAMICS.ORG =3D0ASent: Saturday, March 10, 2012 3:39 AM=3D0A=
Subj=3D
ect: electric kiln problem=3D0A =3D0AI have an electric kiln that I have fi=
red =3D
for 10 years.=3DA0 I fire to cone 6.=3DA0 I mainly =3D0Aused a copper glaze=
, when=3D
I say mainly, I mean majorly, and I think the =3D0Acopper has absorbed int=
o =3D
the kiln brick.=3DA0 Now when I glaze fire, the copper is =3D0Acoming out a=
nd t=3D
inting the other lighter, a yellow and clear glaze, green.=3DA0 Has =3D0Aan=
yone=3D
ever heard of this, or know something i can do to get the copper out.
Steve Mills on sun 11 mar 12
Copper fumes a lot, and if you get a kiln contaminated like that it's almos=
t=3D
impossible to clear without a total re-brick.=3D20
We had a similar problem with the hard brick gas reduction kiln at college;=
s=3D
omeone had put a high copper glaze in it and ever after all white glazes ca=
m=3D
e out pink!
Steve M
Steve Mills
Bath
UK
www.mudslinger.me.uk
Sent from my iPod
On 10 Mar 2012, at 11:39, Kristin Schoonover wrote:
> I have an electric kiln that I have fired for 10 years. I fire to cone 6=
.=3D
I mainly=3D20
> used a copper glaze, when I say mainly, I mean majorly, and I think the=
=3D20=3D
> copper has absorbed into the kiln brick. Now when I glaze fire, the copp=
e=3D
r is=3D20
> coming out and tinting the other lighter, a yellow and clear glaze, green=
.=3D
Has=3D20
> anyone ever heard of this, or know something i can do to get the copper o=
u=3D
t.
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