Paul Herman on mon 25 jan 10
e
Hi Fred,
Thanks for an excellent post. I have a question for you, but will have
to explain a little first.
Some years ago I had a conversation with my friend David W, a ceramic
instrumentation engineer who worked for Honeywell for many years. His
opinion was that it was really dumb to hang the computer right on the
side of the kiln, where the brain gets roasted by radiant heat. He put
his controller over on the wall, several feet from the kiln, and never
had a problem.
My partner Joe bought a new electric kiln to bisque fire in about ten
years ago. It had a controller stuck right on the side of the kiln.
Within a year the brain had been roasted to death, and Joe installed
three manual switches which he continues to use today. I'm lucky with
my Skutt manual kiln for bisquing, it alway works.
The question: In your opinion, should kiln manufacturers put the
controller somewhere else, rather than on the side of the hot kiln?
I wonder how complicated it could be for the manufacturers to just
install a switch to optionally make the kiln into a manual, right from
the factory.
Best wishes,
Paul Herman
Great Basin Pottery
Doyle, California US
www.greatbasinpottery.com/
On Jan 25, 2010, at 4:18 PM, Fredrick Paget wrote:
> Whoa, that sounds like a magic kiln.
>
> Now there is one thing I always held in my mind during the many.
> many years I worked in electricity and electronics -first as a Chief
> Electrician on ships in the old US Merchant Marine and later as an
> electrical engineer after I went back to University and got my BSEE
> and that is:
>
> THERE IS NO SUCH THING AS MAGIC!
>
> There is a logical reason for all the trouble and it just has to be
> found and fixed.
> Here is what I think may be the cause.
>
> The thermocouple wires are not proper thermocouple extension wire or
> if they are they may be hooked up at the kiln end backwards.
>
> First of all here is a primer on thermocouples. rmocouples.html
> >
>
> The type K for instance is made by welding together two heavy pieces
> of wire that go in the kiln, One wire is Nickel-Chromium and the
> other is Nickel-Aluminum.
>
> When you join these two different alloy wires and heat the joint
> you get a tiny electrical voltage generated.
> From there two small extension grade wires are hooked on to the
> thermocouple and run up to the control board.
> These wires are special and in the type k, they each are made out of
> the same alloy as the heavy wire that each one is hooked to. They
> are color coded - red and +yellow.
>
> If they are hooked to the heavy wire of the other alloy you have
> just created two more type k thermocouples in that circuit and when
> th kiln heats up they are on the outside of the kiln but get some
> heat, become active, and who knows what bad result you get.
> At the control board end you no doubt hooked the wires so that if
> you heated the end of the thermocouple in the kiln the temperature
> reading goes up. now heat he outside joints with a hair dryer or
> something and see if it affects the reading, It should not.
>
> Worse yet if some one used plain copper wire for the hookup wire ,
> Instead of type K extension wire you have two unknown thermocouples
> working in the circuit when they get heated up a bit.
>
> -200 you say?
>
> Could be.
>
> Best of luck,
> Fred
Fredrick Paget on sat 30 jan 10
e
Hi all,
I think that error message would be explained in the instruction
manual that came with the kiln. I don't have that manual so I am
guessing that it means one of the couples is reading backward.
My electric kiln setup is in a tiny shack at the top of the hill on
the back of my property. It has a big attic vent fan near the roof
and an air inlet low down .
The controller is a Bartlett in a box on the wall. I have extensivly
modified it . I got it from Bailey along with my small Cone Art kiln
that Bailey sold years ago as a house brand. The kiln is hard wired
into the controller.
I have also an Aim test kiln that runs on 120 volts so I brought out
one side of the 240 and the neutral to a plug box that I can plug the
test kiln into after I turn off the bigger kiln with the kiln sitter
switch and also the two manual switches it has. Also I move the
thermocouple from the bigger kiln to the test kiln . Now the
controller runs the test kiln just fine.
I took out the 40 amp relay that Bailey provided in the wall box and
replaced it with a mercury displacement relay that is far, far
quiter. The old relay sounded like some one using a sledge hammer in
there, and it finally gave up the ghost as I don' t think it was
rated for that kind of service (called bang bang control) anyway.
The Bartlett board has been changed 3 times as I replaced the
original board with newer models, I have one in there now that takes
type S platinum thermcouples . It has inputs for three TC's and an
option for one TC, which I use as my small Cone Art only has two
zones and further I would have to have a separate relay for each zone.
Further I installed a switch to manually turn on the mercury relay so
I can check at the finish of loading that the kiln is properly
turned on with the KS loaded and set and the zone switches on. If
perchance I wanted to run the kiln manually that switch would allow
it in my setup. Not so good if there were multiple zones. It gets
more complex there as you need to turn on three relays at once in the
controller but it can be done.
If I ever wanted to buy another kiln I could buy a manual kiln and
use the same setup for it as long as I stay under 45 amps which is
what the service will provide.
-----Original Message-----
>When I bought my kiln maybe 14 years ago, I paid an extra $100 to buy the
>wall mounted computer controller for exactly that reason. ............
>..........
>It worked .............
>the controller still does its thing.
>.
>Bonnie Hellman
>..
>-----Original Message-----
>From: Clayart [mailto:Clayart@LSV.CERAMICS.ORG] On Behalf Of Paul Herman
>Sent: Monday, January 25, 2010 7:04 PM
>To: Clayart@LSV.CERAMICS.ORG
>Subject: Re: *ClayCraft* Persistent Paragon kiln issue with TCR/-200 messa=
ge
>
>Hi Fred,
>
>Thanks for an excellent post. I have a question for you, but will have
>to explain a little first.
>
>Some years ago I had a conversation with my friend David W, a ceramic
>instrumentation engineer who worked for Honeywell for many years. His
>opinion was that it was really dumb to hang the computer right on the
>side of the kiln, where the brain gets roasted by radiant heat. He put
>his controller over on the wall, several feet from the kiln, and never
>had a problem......
>
>The question: In your opinion, should kiln manufacturers put the
>controller somewhere else, rather than on the side of the hot kiln?
>
>I wonder how complicated it could be for the manufacturers to just
>install a switch to optionally make the kiln into a manual, right from
>the factory.
>..
>
>Paul Herman
.
--
Fred Paget
Twin Dragon Studio
Mill Valley, CA, USA
fredrick@well.com>
Charter Member Potters Council
Bonnie Hellman on sat 30 jan 10
e
When I bought my kiln maybe 14 years ago, I paid an extra $100 to buy the
wall mounted computer controller for exactly that reason. The kiln lived
(and now we live) in a rural area and I was concerned that heat from the
kiln (which has 3" walls) would fry the computer, causing the kiln to be
inoperable. I also liked the idea that the kiln came with a sitter when you
didn't buy the attached computer controller, providing a second control on
the shut-off.
It worked as I thought, and although I've gone through a few thermocouples,
the controller still does its thing.
Bonnie
Bonnie Hellman
Ouray, CO. USA
-----Original Message-----
From: Clayart [mailto:Clayart@LSV.CERAMICS.ORG] On Behalf Of Paul Herman
Sent: Monday, January 25, 2010 7:04 PM
To: Clayart@LSV.CERAMICS.ORG
Subject: Re: *ClayCraft* Persistent Paragon kiln issue with TCR/-200 messag=
e
Hi Fred,
Thanks for an excellent post. I have a question for you, but will have
to explain a little first.
Some years ago I had a conversation with my friend David W, a ceramic
instrumentation engineer who worked for Honeywell for many years. His
opinion was that it was really dumb to hang the computer right on the
side of the kiln, where the brain gets roasted by radiant heat. He put
his controller over on the wall, several feet from the kiln, and never
had a problem.
My partner Joe bought a new electric kiln to bisque fire in about ten
years ago. It had a controller stuck right on the side of the kiln.
Within a year the brain had been roasted to death, and Joe installed
three manual switches which he continues to use today. I'm lucky with
my Skutt manual kiln for bisquing, it alway works.
The question: In your opinion, should kiln manufacturers put the
controller somewhere else, rather than on the side of the hot kiln?
I wonder how complicated it could be for the manufacturers to just
install a switch to optionally make the kiln into a manual, right from
the factory.
Best wishes,
Paul Herman
Great Basin Pottery
Doyle, California US
www.greatbasinpottery.com/
On Jan 25, 2010, at 4:18 PM, Fredrick Paget wrote:
> Whoa, that sounds like a magic kiln.
>
> Now there is one thing I always held in my mind during the many.
> many years I worked in electricity and electronics -first as a Chief
> Electrician on ships in the old US Merchant Marine and later as an
> electrical engineer after I went back to University and got my BSEE
> and that is:
>
> THERE IS NO SUCH THING AS MAGIC!
>
> There is a logical reason for all the trouble and it just has to be
> found and fixed.
> Here is what I think may be the cause.
>
> The thermocouple wires are not proper thermocouple extension wire or
> if they are they may be hooked up at the kiln end backwards.
>
> First of all here is a primer on thermocouples.
> >
>
> The type K for instance is made by welding together two heavy pieces
> of wire that go in the kiln, One wire is Nickel-Chromium and the
> other is Nickel-Aluminum.
>
> When you join these two different alloy wires and heat the joint
> you get a tiny electrical voltage generated.
> From there two small extension grade wires are hooked on to the
> thermocouple and run up to the control board.
> These wires are special and in the type k, they each are made out of
> the same alloy as the heavy wire that each one is hooked to. They
> are color coded - red and +yellow.
>
> If they are hooked to the heavy wire of the other alloy you have
> just created two more type k thermocouples in that circuit and when
> th kiln heats up they are on the outside of the kiln but get some
> heat, become active, and who knows what bad result you get.
> At the control board end you no doubt hooked the wires so that if
> you heated the end of the thermocouple in the kiln the temperature
> reading goes up. now heat he outside joints with a hair dryer or
> something and see if it affects the reading, It should not.
>
> Worse yet if some one used plain copper wire for the hookup wire ,
> Instead of type K extension wire you have two unknown thermocouples
> working in the circuit when they get heated up a bit.
>
> -200 you say?
>
> Could be.
>
> Best of luck,
> Fred
Maurice Weitman on sat 30 jan 10
e
Hi, Bonnie, Paul, Fred, friends, and parents,
At 11:39 -0700 on 1/30/10, Bonnie Hellman wrote:
>When I bought my kiln maybe 14 years ago, I paid an extra $100 to buy the
>wall mounted computer controller for exactly that reason. The kiln lived
>(and now we live) in a rural area and I was concerned that heat from the
>kiln (which has 3" walls) would fry the computer, causing the kiln to be
>inoperable. I also liked the idea that the kiln came with a sitter when yo=
u
>didn't buy the attached computer controller, providing a second control on
>the shut-off.
>
>It worked as I thought, and although I've gone through a few thermocouples=
,
>the controller still does its thing.
A couple of questions, Bonnie:
I assume you're referring to the Skutt KM-1 Wall Mount Controller
that's hooked into your Skutt manual kiln.
Does the kiln have one or three thermocouples (and therefore zones
which the controller will work to keep even)? All
computer-controlled kilns I've seen from about 5 cubic feet up use
three.
I agree that heat and electronics don't mix well, but when I looked
into the wall-mount option, it seemed like all the outboard
controllers only worked with one 'couple, and the zoned firing was
not available.
Does your kiln plug into or is it hard-wired to the controller? If
the latter, it would seem that if the controller was knocked out, so
would be the chance to use the kiln manually (without significant
work).
I've posted this before, but I found it to be trivial to mount a 3"
muffin fan to the bottom of the chase where my controller is mounted,
and it, and the other components within stay cool throughout and
after the firing.
The Bailey kiln I have (with built-in Bartlett controller) also came
with a kiln sitter.
Paul Herman wrote:
>[...] should kiln manufacturers put the
>controller somewhere else, rather than on the side of the hot kiln?
The heat issue is important, but as I wrote above, there are other
ways to fix that.
But there are other benefits to having an external controller: for
one, it can be used to control multiple kilns, though obviously not
at the same time. I built an external box using a Bartlett
controller to control two, small kilns, an Aim 88 "test" kiln, and a
smaller Duncan that I used for small loads. Works great!
>Fred Paget wrote:
> > THERE IS NO SUCH THING AS MAGIC!
Oh, Fred, you know better than that! Every day is magic!!!
> > -200 you say?
>>
>> Could be.
I'll bet the -200 isn't a reading... maybe it's their way of saying
that it's t'couple #2?
I miss you, Fred! When are you and Nan moving to New York?
Regards,
Maurice
May Luk on sun 31 jan 10
e
Hello Fred and whoever's interested in electric kilns:
The -200 (C or -328F) is memory corruption according to Arnold. It is
not in the manual.
I have put in snubber network and a shield provided by Paragon to
shield out electrical noise. I am still getting the error message.
(This is what I've done Friday:
http://www.flickr.com/photos/yamerica/4314187896/in/set-72157623320127930/)
I did not do the element changed, but is it possible to have the lead
wires reversed while replacing the elements? Is taking out the wires
part of changing elements and relays?
I don't know what to do next. The controller maker is going to contact
me. I am looking into worst case scenario. (how much $$$ and how long
maximum production down time)
Meanwhile, I am enjoying my new Studio Potter magazine. Page 20: How
Many $40 Cups Does It Take To Buy A House?
Have a nice day!
May
On Sun, Jan 31, 2010 at 1:38 AM, Fredrick Paget wrote:
> Hi all,
> I think that error message would be explained in the instruction
> manual that came with the kiln. I don't have that manual so I am
> guessing that it means one of the couples is reading backward.
>
--
http://twitter.com/MayLuk
Arnold Howard on mon 1 feb 10
e
From: "May Luk"
> I did not do the element changed, but is it possible to
> have the lead
> wires reversed while replacing the elements? Is taking out
> the wires
> part of changing elements and relays?
>
> I don't know what to do next.
------------
Don't worry about your kiln, May. This is not a difficult
problem.
Each end of the thermocouple wires must be connected to the
correct terminals. One end connects to the back of the
controller, and the other end to the thermocouple ceramic
connection block. The connections on the controller and
block are color-coded.
The wire colors
Type-K thermocouple: yellow wire (+) and red wire (-)
brown and yellow outer insulation
Type-S & R thermocouples: black wire (+) and red wire (-)
green outer insulation
Paragon's thermocouples
Type-K: Black or metallic metal sheath
Type-S: White ceramic 1/4" wide protection tube
The correct thermocouple must be selected in the TC option
(using the Option key).
The thermocouple wires must be kept away from the
relay-to-element wires. This applies to any brand of
controller. Also, the electric circuit must have a good
grounding wire.
Sincerely,
Arnold Howard
Paragon Industries, L.P., Mesquite, Texas USA
ahoward@paragonweb.com / www.paragonweb.com
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