Home grown Kiln controller - Electric Mid&Hi Fired Ceramics2024-03-29T01:27:13Zhttps://cone6pots.ning.com/forum/topics/home-grown-kiln-controller?commentId=2103784%3AComment%3A127352&xg_source=msg_com_forum&feed=yes&xn_auth=noHi,
The only check we do is w…tag:cone6pots.ning.com,2016-01-13:2103784:Comment:1272262016-01-13T16:45:41.776ZMarina Reijsmeijer (Kleierij)https://cone6pots.ning.com/profile/MarinaReijsmeijerKleierij
<p>Hi,</p>
<p>The only check we do is whether the kiln temperature is below or above the graph (stookplan). If it is below the kiln relais switches the kiln on, always full power. As you can see from my previous picture, at 1100C the temperature does not reach the graph anymore, so it keeps firing. which is ok as long as the ramp/plan does not start the cooling until the required temperature and hold are reached. I do a manual extension of the peak of the graph to establish this and I watch the…</p>
<p>Hi,</p>
<p>The only check we do is whether the kiln temperature is below or above the graph (stookplan). If it is below the kiln relais switches the kiln on, always full power. As you can see from my previous picture, at 1100C the temperature does not reach the graph anymore, so it keeps firing. which is ok as long as the ramp/plan does not start the cooling until the required temperature and hold are reached. I do a manual extension of the peak of the graph to establish this and I watch the firing until it can start cooling. No clever algorithm here. I just watch it for a half hour or so.</p>
<p>Below the ui for creating and changing the graph. Sorry all in Dutch :)</p>
<p>I think your algorithm will work as long as you take an average of several temperature measurements and reject spikes. Do you intend to change the firing plan accordingly? You may want all 3, the original plan, the adapted plan and the actual firing data.</p>
<p>The x is hours y is temp C. I ran it without a thermocouple, hence the error.</p>
<p><a href="http://storage.ning.com/topology/rest/1.0/file/get/3127173616?profile=original" target="_self"><img width="721" src="http://storage.ning.com/topology/rest/1.0/file/get/3127173616?profile=RESIZE_1024x1024" width="721" class="align-left"/></a><br/> <br/> <cite>Robert Coyle said:</cite></p>
<blockquote cite="http://cone6pots.ning.com/forum/topics/home-grown-kiln-controller#2103784Comment127276"><div><div class="xg_user_generated"><p>I attached a pdf report file from my app. and a couple of screen shots of the user interface It is not a real run I did it with a potentiometer attached to the Arduino rather than a thermocouple.</p>
<p></p>
<p>I am coding some logic to address the problem of kiln lag time. I am going to start out simple. Every minute I will check to see if the measured temperature is within 10 degrees of the target temperature. If it is, I go on to the next increment, if not I do not advance the temperature. The run time plot on the graph will keep advancing in either case, so you will know what the kiln really did.</p>
<p>Any ideas would be helpful</p>
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</blockquote> I attached a pdf report file…tag:cone6pots.ning.com,2016-01-13:2103784:Comment:1272762016-01-13T16:11:07.540ZRobert Coylehttps://cone6pots.ning.com/profile/RobertCoyle
<p>I attached a pdf report file from my app. and a couple of screen shots of the user interface It is not a real run I did it with a potentiometer attached to the Arduino rather than a thermocouple.</p>
<p></p>
<p>I am coding some logic to address the problem of kiln lag time. I am going to start out simple. Every minute I will check to see if the measured temperature is within 10 degrees of the target temperature. If it is, I go on to the next increment, if not I do not advance the…</p>
<p>I attached a pdf report file from my app. and a couple of screen shots of the user interface It is not a real run I did it with a potentiometer attached to the Arduino rather than a thermocouple.</p>
<p></p>
<p>I am coding some logic to address the problem of kiln lag time. I am going to start out simple. Every minute I will check to see if the measured temperature is within 10 degrees of the target temperature. If it is, I go on to the next increment, if not I do not advance the temperature. The run time plot on the graph will keep advancing in either case, so you will know what the kiln really did.</p>
<p>Any ideas would be helpful</p> Thanks, it is an excellent id…tag:cone6pots.ning.com,2016-01-13:2103784:Comment:1274582016-01-13T10:49:03.290ZMarina Reijsmeijer (Kleierij)https://cone6pots.ning.com/profile/MarinaReijsmeijerKleierij
<p>Thanks, it is an excellent idea. It will be much more fun to learn to interface with Arduino than to try and communicate with an unsupported voltmeter. Very kind of you to share the code.</p>
<p>I think the discussion covered all features a controller needs. Mine works with a firing plan that can be input with mouse clicks or by selecting desired temperatures and the rates. I have no warnings for a firing that does not reach the required temperature. I just go and look how it goes when it is…</p>
<p>Thanks, it is an excellent idea. It will be much more fun to learn to interface with Arduino than to try and communicate with an unsupported voltmeter. Very kind of you to share the code.</p>
<p>I think the discussion covered all features a controller needs. Mine works with a firing plan that can be input with mouse clicks or by selecting desired temperatures and the rates. I have no warnings for a firing that does not reach the required temperature. I just go and look how it goes when it is 1100C. Sometimes it stays below the curve and i change the graph so it will reach it. The blue line is the input, the red the actual firing. I'd be happy to share the code with you, but it is not very well documented. The program ignores the spikes from the thermocouple.<a href="http://storage.ning.com/topology/rest/1.0/file/get/3127174955?profile=original" target="_self"><img width="721" src="http://storage.ning.com/topology/rest/1.0/file/get/3127174955?profile=RESIZE_1024x1024" width="721" class="align-left"/></a><br/> <br/> <cite>Robert Coyle said:</cite></p>
<blockquote cite="http://cone6pots.ning.com/forum/topics/home-grown-kiln-controller#2103784Comment127271"><div><div class="xg_user_generated"><p>I put all of the code, jars, dll,s etc into a zip file on my website</p>
<p><a rel="nofollow" href="http://raventreestudios.com/kiln_wiz.zip" target="_blank">kiln controller link</a></p>
<p>Buy a cheap Arduino UNO and give it a try.... Read the readme.txt file for more info</p>
<p></p>
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</blockquote> I put all of the code, jars,…tag:cone6pots.ning.com,2016-01-12:2103784:Comment:1272712016-01-12T20:26:28.767ZRobert Coylehttps://cone6pots.ning.com/profile/RobertCoyle
<p>I put all of the code, jars, dll,s etc into a zip file on my website</p>
<p><a href="http://raventreestudios.com/kiln_wiz.zip" target="_blank">kiln controller link</a></p>
<p>Buy a cheap Arduino UNO and give it a try.... Read the readme.txt file for more info</p>
<p></p>
<p>I put all of the code, jars, dll,s etc into a zip file on my website</p>
<p><a href="http://raventreestudios.com/kiln_wiz.zip" target="_blank">kiln controller link</a></p>
<p>Buy a cheap Arduino UNO and give it a try.... Read the readme.txt file for more info</p>
<p></p> Marina Reijsmeijer (Kleieri…tag:cone6pots.ning.com,2016-01-12:2103784:Comment:1273582016-01-12T16:09:10.737ZRobert Coylehttps://cone6pots.ning.com/profile/RobertCoyle
<p><br></br> <br></br> <cite>Marina Reijsmeijer (Kleierij) said:</cite></p>
<blockquote cite="http://cone6pots.ning.com/forum/topics/home-grown-kiln-controller?commentId=2103784%3AComment%3A127352&xg_source=msg_com_forum#2103784Comment127352"><div><div class="xg_user_generated"><p>I have a home built controller as well and because it is having problems I have a question for you. My thermocouple is connected to a multimeter with an RS232 interface to a laptop. The multimeter is old and I need to…</p>
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<p><br/> <br/> <cite>Marina Reijsmeijer (Kleierij) said:</cite></p>
<blockquote cite="http://cone6pots.ning.com/forum/topics/home-grown-kiln-controller?commentId=2103784%3AComment%3A127352&xg_source=msg_com_forum#2103784Comment127352"><div><div class="xg_user_generated"><p>I have a home built controller as well and because it is having problems I have a question for you. My thermocouple is connected to a multimeter with an RS232 interface to a laptop. The multimeter is old and I need to replace it. Does your controller use a multimeter too or can Arduino measure voltages? I am trying to find a replacement multimeter with a published protocol, preferably C or C#. I have found multimeters with an RS232 or USB output, but no api/protocol..</p>
<p></p>
<p>The Arduino has multiple 10 bit A/D converters. It reads from 0 to 5 Volts in 1/1024 divisions. This is plenty for a kiln controller. The Arduino is programmed in C. There is lots of info on the Arduino web site on just how to do this and how to interface from a thermocouple either through the analog in or through the MAX 31855 chip,which is designed for this application. The Arduino connects directly to the computer through a USB port.</p>
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</blockquote> I have a home built controlle…tag:cone6pots.ning.com,2016-01-12:2103784:Comment:1273522016-01-12T10:40:38.445ZMarina Reijsmeijer (Kleierij)https://cone6pots.ning.com/profile/MarinaReijsmeijerKleierij
<p>I have a home built controller as well and because it is having problems I have a question for you. My thermocouple is connected to a multimeter with an RS232 interface to a laptop. The multimeter is old and I need to replace it. Does your controller use a multimeter too or can Arduino measure voltages? I am trying to find a replacement multimeter with a published protocol, preferably C or C#. I have found multimeters with an RS232 or USB output, but no api/protocol..</p>
<p>I have a home built controller as well and because it is having problems I have a question for you. My thermocouple is connected to a multimeter with an RS232 interface to a laptop. The multimeter is old and I need to replace it. Does your controller use a multimeter too or can Arduino measure voltages? I am trying to find a replacement multimeter with a published protocol, preferably C or C#. I have found multimeters with an RS232 or USB output, but no api/protocol..</p> Interesting link Chuck, I dow…tag:cone6pots.ning.com,2015-12-23:2103784:Comment:1271542015-12-23T17:28:04.812ZRobert Coylehttps://cone6pots.ning.com/profile/RobertCoyle
<p>Interesting link Chuck, I downloaded the code.</p>
<p>My application is pretty basic. I don't use PID, just measure temp every second or so and turn things on or off. If you look close there is some temperature wobble but over a 1000 + degrees, it looks to follow the ramp curve pretty close. I have been using this type of control for about six years now and never had a problem. I switched over from VB to java for my front end and slightly modified the control algorithms. Gave it a test…</p>
<p>Interesting link Chuck, I downloaded the code.</p>
<p>My application is pretty basic. I don't use PID, just measure temp every second or so and turn things on or off. If you look close there is some temperature wobble but over a 1000 + degrees, it looks to follow the ramp curve pretty close. I have been using this type of control for about six years now and never had a problem. I switched over from VB to java for my front end and slightly modified the control algorithms. Gave it a test run the other day and it seems to work fine. I need to add logic that insures end points of ramp cycles. The old VB logic didn't proceed to the next ramp until the endpoint of the last was detected. This meant that if the temperature lagged, you still had to ramp up at the rate designated by the next segment, even though that might be slower and you might want catch up. I might add some logic that sees we are running slow, and tries to ramp up faster to try to get back on time.</p>
<p>As for heat work, I just start my calculations at 1200 F. I figure anything before then is just driving out water. My ramp endpoints are still temperature, but it would be possible to use calculated heat work maybe instead of maximum attained temperature. I don't think anyone does this.</p>
<p>If you ( or anyone) wants a copy of my app to play with, send me an e-mail and I'll get it to you.</p> I am on the same journey but…tag:cone6pots.ning.com,2015-12-23:2103784:Comment:1269792015-12-23T04:33:50.712ZChuck Colhthttps://cone6pots.ning.com/profile/ChuckColht
<p>I am on the same journey but perhaps not as far along. My setup uses 2 40 amp SSRs, one for each set of 4 elements in an old Duncan kiln. The new element sets draw about 20 amps each so the 40 amp each rating covers that. SSRs can fail on so I am keeping the mechanical timer to cut power if it fires too long. The SSRs are on the cold side of that. I also put a NO relay on the control lines that must be armed with a pushbutton (power feeds back from the cold side of the contacts to the coil)…</p>
<p>I am on the same journey but perhaps not as far along. My setup uses 2 40 amp SSRs, one for each set of 4 elements in an old Duncan kiln. The new element sets draw about 20 amps each so the 40 amp each rating covers that. SSRs can fail on so I am keeping the mechanical timer to cut power if it fires too long. The SSRs are on the cold side of that. I also put a NO relay on the control lines that must be armed with a pushbutton (power feeds back from the cold side of the contacts to the coil) to allow the signal to reach the relays. In other words, if power is lost or a safety trips, the SSRs will stay off even if the controller wants them on. If they stick on, the mechanical timer will cut the main power eventually. </p>
<p>Heat work can be measured as the area under the curve of the temp over time. Math speak for adding up the difference between some 'floor' (say 1900 or where ever the material starts to be affected) and the current temp every sample time. This means that a fast rise to a high temp is the same as a slow rise to a lower (but still high enough) temp. If you graph the temp near the top using different rates, you should see what I mean. Temp going down but over the floor still counts. The magic is in that floor temp. I don't have any good refs on that and will start out just guessing, based on measurements from my computerized Skutt.</p>
<p>I am starting with a 60 second cycle, dividing the rate/hour by the cycle and the difference between current and target by the same number to get the next set temp. But a kiln is pretty sluggish going up compared to going down and I'm having trouble tuning the PID.</p>
<p>Right now I am controlling it manually using a front end I found here: </p>
<p><a href="http://brettbeauregard.com/blog/category/pid/front-end/" target="_blank">http://brettbeauregard.com/blog/category/pid/front-end/</a></p>
<p>Great stuff and an excellent into to PID theory. </p> Yeah Norm, the price of contr…tag:cone6pots.ning.com,2015-12-18:2103784:Comment:1270532015-12-18T19:46:46.178ZRobert Coylehttps://cone6pots.ning.com/profile/RobertCoyle
<p>Yeah Norm, the price of controllers has come down a lot over the past few years. The advantage of a PC based system is portability. I have three kilns and just plug in the themocouple leads and relay leads into the PC controller. They all have single thermocouple control to solid state relays, so I just need one. I also can use the PC to print out custom run reports which is handy.</p>
<p>Yeah Norm, the price of controllers has come down a lot over the past few years. The advantage of a PC based system is portability. I have three kilns and just plug in the themocouple leads and relay leads into the PC controller. They all have single thermocouple control to solid state relays, so I just need one. I also can use the PC to print out custom run reports which is handy.</p> If you install solid state re…tag:cone6pots.ning.com,2015-12-18:2103784:Comment:1270522015-12-18T19:00:39.516ZNorm Stuarthttps://cone6pots.ning.com/profile/NormStuart
<p>If you install solid state relays, in the hidden menu you can choose a CYCL time of 0 for turning the elements on and off, which creates a 200 ms cycle time, according to the V6-CF technical manual.</p>
<p><a href="http://www.bartinst.com/kilns/1" rel="nofollow" target="_blank">http://www.bartinst.com/kilns/1</a></p>
<p></p>
<p>My recollection of talking to the Tech Support at Bartlett was the heat work was determined by recording the temperature every three seconds. They could confirm the…</p>
<p>If you install solid state relays, in the hidden menu you can choose a CYCL time of 0 for turning the elements on and off, which creates a 200 ms cycle time, according to the V6-CF technical manual.</p>
<p><a rel="nofollow" href="http://www.bartinst.com/kilns/1" target="_blank">http://www.bartinst.com/kilns/1</a></p>
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<p>My recollection of talking to the Tech Support at Bartlett was the heat work was determined by recording the temperature every three seconds. They could confirm the actual timing for you, after they return in January. It's a pretty robustly designed controller. Making your own controller is a fun project, but the V6-CF controller by itself has a retail price of only $219.</p>
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<p>The Bartlett V6-CF is on the left. Our Cress E23 kiln has a customized version of the V6-CF shown on the right.</p>
<p><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3127174916?profile=original"><img width="721" class="align-left" src="http://storage.ning.com/topology/rest/1.0/file/get/3127174916?profile=RESIZE_1024x1024" width="721"/></a></p>
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<p>.</p>
<p>Most buy a more costly $530 retrofit kit which includes a box for the controller along with a step-down transformer, fuse, power-switch, and thermocouple designed to replace a kiln-sitter. It's the controller on the far left. I'm sure you'd be buying only the V6-CF controller from Bartlett and adding the rest yourself.</p>
<p><a rel="nofollow" href="http://www.clay-king.com/kilns/olympic_kilns/electro_sitter.htmls" target="_blank">http://www.clay-king.com/kilns/olympic_kilns/electro_sitter.htmls</a></p>
<p><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/3127175264?profile=original"><img width="721" class="align-left" src="http://storage.ning.com/topology/rest/1.0/file/get/3127175264?profile=RESIZE_1024x1024" width="721"/></a></p>
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