DIY Temperature Controller for Heating Blankets - FRETS.NET2024-03-28T15:42:13Zhttp://fretsnet.ning.com/forum/topics/diy-temperature-controller-for-heating-blankets?commentId=2177249%3AComment%3A116084&feed=yes&xn_auth=noThanks much!tag:fretsnet.ning.com,2014-07-31:2177249:Comment:1355992014-07-31T17:01:07.147ZNate Scotthttp://fretsnet.ning.com/profile/NateScott
<p>Thanks much!</p>
<p>Thanks much!</p> Hi Nate,
I bought the project…tag:fretsnet.ning.com,2014-07-30:2177249:Comment:1355842014-07-30T22:44:54.859ZRobbie Collinshttp://fretsnet.ning.com/profile/RobbieCollins
<p>Hi Nate,</p>
<p>I bought the project box on eBay for $18.97 plus $7.15 shipping. It is 6.6" x 5.9" x 2.78." So far it has worked flawlessly. The seller was jpmultiserve:…</p>
<p></p>
<p>Hi Nate,</p>
<p>I bought the project box on eBay for $18.97 plus $7.15 shipping. It is 6.6" x 5.9" x 2.78." So far it has worked flawlessly. The seller was jpmultiserve:</p>
<p><a href="http://www.ebay.com/sch/m.html?_odkw=&_osacat=0&_armrs=1&_ssn=jpmultiserve&_trksid=p2046732.m570.l1313.TR10.TRC0.A0.H0.Xbox&_nkw=box&_sacat=0&_from=R40" target="_blank">http://www.ebay.com/sch/m.html?_odkw=&_osacat=0&_armrs=1&_ssn=jpmultiserve&_trksid=p2046732.m570.l1313.TR10.TRC0.A0.H0.Xbox&_nkw=box&_sacat=0&_from=R40</a></p>
<p>If he doesn't list it you might send him a message.</p>
<p>Good Luck, Robbie</p> Nice controller box build, Ro…tag:fretsnet.ning.com,2014-07-28:2177249:Comment:1352562014-07-28T19:19:52.638ZNate Scotthttp://fretsnet.ning.com/profile/NateScott
<p>Nice controller box build, Robbie. I'm collecting parts to make one for myself. What are the dimensions of your enclosure? Source?</p>
<p>Nice controller box build, Robbie. I'm collecting parts to make one for myself. What are the dimensions of your enclosure? Source?</p> I like the temperature conver…tag:fretsnet.ning.com,2013-09-27:2177249:Comment:1189742013-09-27T17:59:49.254ZJ R Emmetthttp://fretsnet.ning.com/profile/JREmmett
<p>I like the temperature conversion label :-). Unfortunately, the only metric units that I think in are Temperature and Mass (grams). Your controller may have a setting to display temperatures in either unit. </p>
<p> </p>
<p>I'll offer a link to this page as it contains converters for nearly everything.</p>
<p> </p>
<p><a href="http://onlineconversion.com/">http://onlineconversion.com/</a></p>
<p> </p>
<p>Great job on the project Robbie. Look forward to seeing the test reports.</p>
<p>I like the temperature conversion label :-). Unfortunately, the only metric units that I think in are Temperature and Mass (grams). Your controller may have a setting to display temperatures in either unit. </p>
<p> </p>
<p>I'll offer a link to this page as it contains converters for nearly everything.</p>
<p> </p>
<p><a href="http://onlineconversion.com/">http://onlineconversion.com/</a></p>
<p> </p>
<p>Great job on the project Robbie. Look forward to seeing the test reports.</p> Auto tune is not about calibr…tag:fretsnet.ning.com,2013-09-27:2177249:Comment:1192492013-09-27T17:55:51.201ZJ R Emmetthttp://fretsnet.ning.com/profile/JREmmett
<p>Auto tune is not about calibration or accuracy of temperature. If you want to check accuracy - place the thermocouple probe in a bucket of ice water (should read near zero degrees C) and then in a pot of boiling water (should read near 100 degrees C).</p>
<p> </p>
<p>Autotune sets up the parameters for the PID controller to provide precise temperature control - particularly in the transient (warm up) state. If the PID parameters are incorrectly set, you will see gross setpoint overshoot…</p>
<p>Auto tune is not about calibration or accuracy of temperature. If you want to check accuracy - place the thermocouple probe in a bucket of ice water (should read near zero degrees C) and then in a pot of boiling water (should read near 100 degrees C).</p>
<p> </p>
<p>Autotune sets up the parameters for the PID controller to provide precise temperature control - particularly in the transient (warm up) state. If the PID parameters are incorrectly set, you will see gross setpoint overshoot (a few degrees is normal) during warm up and you may also see an oscillating temperature that never stabilizes around the setpoint. In the "old" days, we used to enter the parameters manually and iterate them until we had a stable temperature with low overshoot. Autotune was a godsend as most controllers will develop better parameters than I ever could. Check your manual - it should have instructions about how to use this feature. Typically, you set the parameter to 1 and then turn on the heater and let autotune do it's thing as the system warms up. If you power cycle the temperature controller, I suspect you will find the autotune parameter set to 0. </p> J.R. - how does the Autotune…tag:fretsnet.ning.com,2013-09-26:2177249:Comment:1189422013-09-26T04:01:38.920ZRobbie Collinshttp://fretsnet.ning.com/profile/RobbieCollins
<p>J.R. - how does the Autotune feature work? I assume this an auto-calibration feature? I set Autotune=1 in the setup menu. It seems like this would be a one-time deal.</p>
<p>What's confusing is that auto-calibration would need feedback from a second sensor or for the operator to input the actual blanket temperature read with, say, an infrared thermometer.</p>
<p>J.R. - how does the Autotune feature work? I assume this an auto-calibration feature? I set Autotune=1 in the setup menu. It seems like this would be a one-time deal.</p>
<p>What's confusing is that auto-calibration would need feedback from a second sensor or for the operator to input the actual blanket temperature read with, say, an infrared thermometer.</p> I finally received the heatin…tag:fretsnet.ning.com,2013-09-26:2177249:Comment:1189412013-09-26T03:57:49.971ZRobbie Collinshttp://fretsnet.ning.com/profile/RobbieCollins
<p>I finally received the heating blanket from LMII and was able to test my controller. I set it to 121C (250F) and it took the blanket about 3 minutes to get to that temp. Unfortunately, I can't lay my hands on my infrared thermometer to check it.</p>
<p>The unit is has two readouts for PV and SV. PV means Processed Value and is the thermocouple reading. SV is the Set Value or the temperature you want. When the unit boots it gives the general parameter settings on the PV and SV LED…</p>
<p>I finally received the heating blanket from LMII and was able to test my controller. I set it to 121C (250F) and it took the blanket about 3 minutes to get to that temp. Unfortunately, I can't lay my hands on my infrared thermometer to check it.</p>
<p>The unit is has two readouts for PV and SV. PV means Processed Value and is the thermocouple reading. SV is the Set Value or the temperature you want. When the unit boots it gives the general parameter settings on the PV and SV LED readouts. Mine said it was configured for a K thermocouple which is what I'm using.</p>
<p>Setting the temperature requires pressing the Set button which highlights the right hand side digit. Pressing it again gets the 2nd digit, etc. I set it to 121C then turned off the unit. The unit rebooted with SV=121.</p>
<p>Wiring the DC output to the SS Relay, I couldn't figure which screw (4 or 5) was positive. The SSR is marked + and - so I assume it cares. I checked the output with my Fluke and got 13.68v but swapping test leads got the same value. I thought it would read +13.68 or -13.68 depending on whether the positive lead was on the positive output, etc.</p>
<p>If SV > PV then the controller should kick on the relay, but the red relay LED wasn't on. So, I swapped the control wires on the SSR, played with the internal menus, power cycled the unit and the SSR came on. So, I don't know whether it was wired backwards or not.</p>
<p>I turned Autotune on, but truthfully I don't know what it does. Auto-calibration?</p>
<p>So far, so good! Tomorrow I will attempt to remove a fingerboard and will report back. Any ideas on the initial temp for removing a bound fingerboard?</p>
<p>The mess around the rear connections is hot glue. My dremeling wasn't very exact.</p>
<p><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/2167746738?profile=original"><img class="align-full" src="http://storage.ning.com/topology/rest/1.0/file/get/2167746738?profile=original" width="600"/></a><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/2167747769?profile=original"><img class="align-full" src="http://storage.ning.com/topology/rest/1.0/file/get/2167747769?profile=original" width="600"/></a></p> Awesome - very nice construct…tag:fretsnet.ning.com,2013-09-13:2177249:Comment:1182892013-09-13T17:37:16.852ZJ R Emmetthttp://fretsnet.ning.com/profile/JREmmett
<p>Awesome - very nice construction of the control box and a professional wiring job! One source (although a bit expensive) for all things temperature control that I've used for years is Omega Engineering. Great source for thermocouples, plugs, sockets, controllers and wire. </p>
<p> </p>
<p><a href="http://www.omega.com/">http://www.omega.com/</a></p>
<p> </p>
<p>Just one note on thermocouples - for absolute accuracy, all connections from the controller to the thermocouple should be the…</p>
<p>Awesome - very nice construction of the control box and a professional wiring job! One source (although a bit expensive) for all things temperature control that I've used for years is Omega Engineering. Great source for thermocouples, plugs, sockets, controllers and wire. </p>
<p> </p>
<p><a href="http://www.omega.com/">http://www.omega.com/</a></p>
<p> </p>
<p>Just one note on thermocouples - for absolute accuracy, all connections from the controller to the thermocouple should be the proper type of wire and sockets. You may see a degree or two of temperature offset in your controller, which should not matter for this application. Also, a general rule of thumb for temperature control accuracy is that a +/- 2C error in any system like this is typical (and acceptable).</p>
<p> </p>
<p>When you get your heaters, you will need to tune your controller. The Omega site has pretty good technical information about PID controllers and setting parameters. Most modern controllers have an "auto tune" (no vocal talent jokes, please :-) ) feature that will get you very close. If you run into issues (slow to reach temperature, unstable temperature, etc) send me a message and I'll do my best to help.</p> I finally got all the parts i…tag:fretsnet.ning.com,2013-09-10:2177249:Comment:1178002013-09-10T01:30:52.608ZRobbie Collinshttp://fretsnet.ning.com/profile/RobbieCollins
<p>I finally got all the parts in from China:</p>
<p><a href="http://storage.ning.com/topology/rest/1.0/file/get/2167743912?profile=original" target="_self"><img class="align-full" src="http://storage.ning.com/topology/rest/1.0/file/get/2167743912?profile=original" width="600"></img></a> Yesterday I cut the holes in the Enclosure with a Dremel and a Gyros ST carbide wheel. If you haven't tried them they are a couple of inches in diameter and very robust. Lasts much longer than a little Dremel wheel. Today I wired it up using wire I stripped from a IEC AC cord and some connectors from Harbor Freight. I found…</p>
<p>I finally got all the parts in from China:</p>
<p><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/2167743912?profile=original"><img class="align-full" src="http://storage.ning.com/topology/rest/1.0/file/get/2167743912?profile=original" width="600"/></a>Yesterday I cut the holes in the Enclosure with a Dremel and a Gyros ST carbide wheel. If you haven't tried them they are a couple of inches in diameter and very robust. Lasts much longer than a little Dremel wheel. Today I wired it up using wire I stripped from a IEC AC cord and some connectors from Harbor Freight. I found an old aluminum Pentium heat sink, cut it to size with the bandsaw, and installed it on the solid state relay base with heat sink compound. I then attached it to the bottom of the enclosure using the screws that held the fan. I drilled some holes under the heat sink for ventilation.</p>
<p><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/2167744122?profile=original"><img class="align-full" src="http://storage.ning.com/topology/rest/1.0/file/get/2167744122?profile=original" width="600"/></a><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/2167744162?profile=original"><img class="align-full" src="http://storage.ning.com/topology/rest/1.0/file/get/2167744162?profile=original" width="600"/></a>Here's it plugged in. You may notice that there are two fuses. One that's part of the AC input/switch/fuse combo and a standalone fuse. The input fuse is 250v 5A and basically protects against surge and excessive draw from the controller or relay. The other fuse is wired between the relay and the heating blanket and protects the relay from excessive draw from the blanket. I have a 120v 6A fuse which by Ohm's Law W=V*A = 720w which is about 13% more than the largest side bending blanket from LMI draws.</p>
<p>My blankets still haven't arrived. When they do I'll start posting on the Trini Lopez Fingerboard thread I started.</p>
<p><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/2167744284?profile=original"><img class="align-full" src="http://storage.ning.com/topology/rest/1.0/file/get/2167744284?profile=original" width="600"/></a><a target="_self" href="http://storage.ning.com/topology/rest/1.0/file/get/2167744239?profile=original"><img class="align-full" src="http://storage.ning.com/topology/rest/1.0/file/get/2167744239?profile=original" width="600"/></a>I couldn't find a panel mount K-type female jack for the thermocouple so I used a banana plug unit. I'll cap the thermocouple ends with some male banana plugs. Next I'll use my Brother labeling unit and print out some legends. Also need to figure out how to light up the blanket switch on the front. It has three posts...two silver for the switch and a third brass one. Would that go to neutral?</p> I do like steam punk but I'v…tag:fretsnet.ning.com,2013-09-02:2177249:Comment:1169572013-09-02T17:42:45.574ZNed Knepphttp://fretsnet.ning.com/profile/NedKnepp
<p>I do like steam punk but I've never tried to make anything. Wonder if I can work up an acoustic that's steam punk. Maybe a resonator?</p>
<p>I do like steam punk but I've never tried to make anything. Wonder if I can work up an acoustic that's steam punk. Maybe a resonator?</p>