Brad Sondahl on wed 2 aug 00
Lately one of my two 7 cu.ft. Crucible electric kilns has been blowing
the 60 amp breaker too frequently--sometimes 2-3 times in a firing.
Usually it's firing on high for a couple hours before it blows. Then
the breaker cools off, I reset it, and I can get a couple more hours out
of it, or maybe it doesn't blow at all.
When the problem started, the weather was above 90 degrees F--I thought
perhaps the breaker is thermally activated and the additional heat where
the box is might be a contributing factor. But today it's cooler and
still popping.
I've had this problem several years before--in fact replaced a 50 amp
breaker with the 60.
I just recently changed the elements, and did substitute two 14 ga.
elements at the top and bottom (replacing two 16 ga. elements) to help
even out the firing. (Seattle pottery who makes the kiln calls for one
14 ga. at the top and one at the bottom--but I got tired of cool kiln
ends).
I know that breakers can get worn out, especially firing 100 kiln loads
a year.
I'm thinking of buying a new breaker, even a bit larger--65 if they make
them, or 70.
>From my experience, the breaker doesn't do much good for the kiln except
as a switch for servicing--when you're using the amperage a kiln
does--elements, switches, and even plugs can arc away and the breaker
won't pop.
But I'll listen to arguments pro and con on whether I should up the
amperage again or not...
I really don't want to replace the two elements to fix it--the kiln is
firing evenly, and elements aren't cheap...
--
Brad Sondahl
New Homepage: http://pages.about.com/bsondahl/index.html
New commercial pottery page http://sondahl.safeshopper.com
Original literature, music, pottery, and art
Harry on thu 3 aug 00
Brad,
Breakers do go bad. It is possible that the breaker in question is just
falling apart. I have run into that before. You may be better off hiring an
electrician to give it the once over. In fact I hired an electrician to fix
a problem I had with an electric motor, he replaced the whole breaker box
and the problem ended up being the bearings in the motor. I found the
problems with the bearings myself. So there are options for the
do-it-yourselfers. It is a rather expensive toy but you can buy an amperage
meter (or amprobe) to see what amperage is being drawn. You might have a
situation where the breaker is doing what it is suposed to do. What is the
kiln rated for?
Harry
----- Original Message -----
From: "Brad Sondahl"
To:
Sent: Wednesday, August 02, 2000 11:49 PM
Subject: Breaker popping while kiln fires
> Lately one of my two 7 cu.ft. Crucible electric kilns has been blowing
> the 60 amp breaker too frequently--sometimes 2-3 times in a firing.
> Usually it's firing on high for a couple hours before it blows. Then
> the breaker cools off, I reset it, and I can get a couple more hours out
> of it, or maybe it doesn't blow at all.
> When the problem started, the weather was above 90 degrees F--I thought
> perhaps the breaker is thermally activated and the additional heat where
> the box is might be a contributing factor. But today it's cooler and
> still popping.
>
> I've had this problem several years before--in fact replaced a 50 amp
> breaker with the 60.
> I just recently changed the elements, and did substitute two 14 ga.
> elements at the top and bottom (replacing two 16 ga. elements) to help
> even out the firing. (Seattle pottery who makes the kiln calls for one
> 14 ga. at the top and one at the bottom--but I got tired of cool kiln
> ends).
> I know that breakers can get worn out, especially firing 100 kiln loads
> a year.
> I'm thinking of buying a new breaker, even a bit larger--65 if they make
> them, or 70.
>
> From my experience, the breaker doesn't do much good for the kiln except
> as a switch for servicing--when you're using the amperage a kiln
> does--elements, switches, and even plugs can arc away and the breaker
> won't pop.
>
> But I'll listen to arguments pro and con on whether I should up the
> amperage again or not...
> I really don't want to replace the two elements to fix it--the kiln is
> firing evenly, and elements aren't cheap...
>
> --
> Brad Sondahl
> New Homepage: http://pages.about.com/bsondahl/index.html
> New commercial pottery page http://sondahl.safeshopper.com
> Original literature, music, pottery, and art
>
>
____________________________________________________________________________
__
> 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.
>
>
J102551@AOL.COM on thu 3 aug 00
I had this same problem but the fix was simple. Take off the housing over
the kiln sitter and look for discoloration around the holes the elements go
through. My elements were crawling just enough to short out by arcing to the
metal kiln housing. I realigned the little porcelain thingies (In think they
are called buttons) so that they were insulating correctly and no more
problems. As the kiln heated up the elements would crawl just enough to trip
the breaker. When it cooled down the elements would shrink back into place.
It only took a minute to check and was an easy solution. Didn't cost a
thing. Jeri in Hastings, MN
James Bledsoe on thu 3 aug 00
Brad
<
I've had this problem several years before--in fact replaced a 50 amp
breaker with the 60.
I just recently changed the elements, and did substitute two 14 ga.
elements at the top and bottom (replacing two 16 ga. elements) to help
even out the firing. (Seattle pottery who makes the kiln calls for one
14 ga. at the top and one at the bottom--but I got tired of cool kiln
ends).
>
When the new elements increased the current so did the load on the breaker.
This could be the problem. The breaker could be worn. The purpose of the
breaker is to protect the wires. Increasing the size of the breaker could
allow for more electricity than the wire in the wall can carry. (fire
hazard) Some times opening the fuse box and cooling it with a fan will get
you through the rough spots. If you find that you can not keep the kiln
running and need a larger breaker make sure that the wire in the wall can
handle the load you may need replace the wire with a higher gauge say #10
Thin wire may have been the problem all along too.
good luck
Jim
Louis H.. Katz on thu 3 aug 00
Dear Brad,
The breaker is not meant to protect from broken circuits such as a wire arching
to its connector, but to protect from short circuits and other causes of too much
amperage.
Things that I would do are:
1. Get an ohm meter on the elements and get some help determining how much amerage
the kiln may actually be drawing. Euclids might help you with this.
2. Circuit Breakers do get old and then tend to go off more easily. It could be
that. Probably is.
3. Newer elements draw more amps than older ones.
Replacing the breaker with a larger one is dangerous. You could end up with an
electrical fire if there was every a problem.
If you can't resolve the problem with an ohm meter and someone on the phone, hire
an electrician. Make sure to check for shorts to ground. Get one from a place that
does industrial wiring, or someone smart enough to really understand what they are
doing.
Louis
Brad Sondahl wrote:
> Lately one of my two 7 cu.ft. Crucible electric kilns has been blowing
> the 60 amp breaker too frequently--sometimes 2-3 times in a firing.
> Usually it's firing on high for a couple hours before it blows. Then
> the breaker cools off, I reset it, and I can get a couple more hours out
> of it, or maybe it doesn't blow at all.
> When the problem started, the weather was above 90 degrees F--I thought
> perhaps the breaker is thermally activated and the additional heat where
> the box is might be a contributing factor. But today it's cooler and
> still popping.
>
> I've had this problem several years before--in fact replaced a 50 amp
> breaker with the 60.
> I just recently changed the elements, and did substitute two 14 ga.
> elements at the top and bottom (replacing two 16 ga. elements) to help
> even out the firing. (Seattle pottery who makes the kiln calls for one
> 14 ga. at the top and one at the bottom--but I got tired of cool kiln
> ends).
> I know that breakers can get worn out, especially firing 100 kiln loads
> a year.
> I'm thinking of buying a new breaker, even a bit larger--65 if they make
> them, or 70.
>
> >From my experience, the breaker doesn't do much good for the kiln except
> as a switch for servicing--when you're using the amperage a kiln
> does--elements, switches, and even plugs can arc away and the breaker
> won't pop.
>
> But I'll listen to arguments pro and con on whether I should up the
> amperage again or not...
> I really don't want to replace the two elements to fix it--the kiln is
> firing evenly, and elements aren't cheap...
>
> --
> Brad Sondahl
> New Homepage: http://pages.about.com/bsondahl/index.html
> New commercial pottery page http://sondahl.safeshopper.com
> Original literature, music, pottery, and art
>
> ______________________________________________________________________________
> 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.
--
Louis Katz
NEW EMAIL ADDRESS Louis.Katz@mail.tamucc.edu
NCECA Director of Electronic Communication and Webmaster(Ad-Hoc)
Texas A&M-CC Division of Visual and Performing Arts
Visit the NCECA World Ceramics Image Database Online
Looking for a school or a class? Visit NCECA Ceramics Educational Programs
Database Online
chris@euclids.com on thu 3 aug 00
> Lately one of my two 7 cu.ft. Crucible electric kilns has been blowing
> the 60 amp breaker too frequently--sometimes 2-3 times in a firing.
> Usually it's firing on high for a couple hours before it blows
Hi Brad,
The first thing i would do is check the amperage to make sure it is not too
high.
Then i would tighten every connection from the breaker all the way through
to the elements.
You mentioned that it takes a couple of hours on "high" before it blows ...
this points towards loose connections that are heating up.
> I just recently changed the elements, and did substitute two 14 ga.
> elements at the top and bottom (replacing two 16 ga. elements) to help
> even out the firing.
Just make sure that the resistance of the elements are the same. The gauge
of the element will only affect how long it lasts, provided they are the
same resistance. Elements of different resistance produce different amounts
of heat & use different amounts of power.
Other possibilities are a poor quality breaker, inadequate gauge wiring in
power cable or lead wires & poor quality or old switches.
Give us a call if you can`t figure it out.
chris
chris@euclids.com
www.euclids.com
800-296-5456
Kenneth D. Westfall on thu 3 aug 00
Definitely do not change breaker sizes unless you first confirm that the
wiring will handle a larger amp breaker. Your problem may be a faulty
breaker, corrosion, higher amp draw because of new elements, or a shorting
to ground. Best test you could do is to have the amp load checked at the
panel to see what it truly is. That take a amp meter which any competent
electrician should have. Something as simple as a lose set screw on the
breaker can cause nuisance breaker trip. Breakers can over a period of
time and nuisance trip get weak. Main thing is stop using it till you find
the problem.
Kenneth D. Westfall
Pine Hill Pottery
R.D. #2 Box 6AA
Harrisville, WV 26362
pinehill@ruralnet.org
http://www.pinehillpottery.com
Ron Roy on thu 3 aug 00
Hi Brad,
Check the heat on the wires coming from the breaker box - if they are hot
you may just need to tighten connections all along the line.
RR
>Lately one of my two 7 cu.ft. Crucible electric kilns has been blowing
>the 60 amp breaker too frequently--sometimes 2-3 times in a firing.
>Usually it's firing on high for a couple hours before it blows. Then
>the breaker cools off, I reset it, and I can get a couple more hours out
>of it, or maybe it doesn't blow at all.
>When the problem started, the weather was above 90 degrees F--I thought
>perhaps the breaker is thermally activated and the additional heat where
>the box is might be a contributing factor. But today it's cooler and
>still popping.
Ron Roy
93 Pegasus Trail
Scarborough
Ontario, Canada
M1G 3N8
Evenings 416-439-2621
Fax 416-438-7849
Craig Martell on thu 3 aug 00
Hi:
So, if I'm reading your post correctly, you've added two 14ga elements to
the existing two for a total of 4, 14ga elements in your kiln? If this is
so, you have most likely upped the amp draw of the kiln. Talk to Seattle
and get the amps for a 14 and 16 ga element for that kiln and figger out
what your new draw is. The 60 amp breaker may indeed be inadequate now.
Your breakers may pop too when there are loose connections in the supply
circuit or loose plug blades etc. Check to see if there are any burned or
hot looking connections.
later, Craig Martell in Oregon
Gary & Carla Goldberg on thu 3 aug 00
Hi - I had a similar problem. When we had our new house built, I told
them I needed to have an electric hook-up like a stove. Well, a stove
in 50 amps and my kiln needed 60 amps. Of course, I never knew there was
any difference until we moved in.
I tried it anyway, it worked for about 7 runs. Then it died in the
middle of a firing. My brother is an electrical engineer and he told me
what was going on when you run more amps through a wire than it is
designed too...the wires get hot and the house can burn down.
That was enough for me. I had an electrician out and he rewired the
wire from the circuit breaker to the kiln outlet.
Don't mess around with this stuff. Get it fixed.
Carla in Alaska, enjoying our last month of summer. :)
Gary Elfring on fri 4 aug 00
> Breakers do go bad. It is possible that the breaker in question is just
>falling apart. I have run into that before. You may be better off hiring an
>electrician to give it the once over.
I spent my college summers as an electrician, and breakers go bad all the time.
As a general rule, if your breaker has blown several times, it *needs* to be
replaced. An electrician can test to see if the breaker is bad (put a
voltmeter
across the breaker and measure the voltage there under full load- which
should be
close to 0). But since a new 50 or 75 amp breaker only costs $10 - $25, most
electricians simply replace them.
Note that you need to figure out whether or not there is a problem with the
kiln
or it's wiring *before* you replace the breaker. (And fix it.)
Elfring Fonts, Inc Bar Codes, MICR, and decorative fonts for Windows
http://www.elfring.com
| |
|
