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http://www.coleparmer.com/catalog/product_view.asp?sku=9352001

I have the standard 6"x35" 110v heating blanket running with a timer but this seems like it would work for a pretty good price, but I thought I'd ask someone with experience, thanks!

It looks like it. I've used similar controlers in the past, but have had to use a seperate relay, this unit appears to have a 16 amp relay built in, sweet deal.
You'll need thermocouples too.

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Jim Watts
http://jameswattsguitars.com

I'm too cheap to go for a controler. I use a themocouple and temperature multimeter from Harbor Freight and turn the heater (light bulbs) off by hand.

Bob

Yeah, that's what I'm doing now but I need to upgrade my thermometer and I ran across this, seems like the way to go and make my life easier.

I would avoid any unit with an inbuilt relay. That is the component most likely to fail eventually and then you would be up for a new controller. Have a look on ebay for an Omron E5CS-Q and run a separate relay. The E5CS-R has an inbuilt relay but it low amp out still requires a separate larger external relay to run a heat blanket. Also recommend a digital timer to be hooked into the loop as it allows fail safe timed cycles. With such a system you can fine tune and log all of your thickness, heat and time combinations for different woods. Then simply dial them in and hit the go button with few worries about broken sides or scorching.

Here's mine, I could have made it more compact but pretty lights and shiny metal with lots of holes are 'very' important as I am a Dr Who fan.



Cheers

Kim

jeesh! That looks like something out of a Bond film! I'm sure it works nice but do you really need it? I got one from Ebay that works like a dream and is quite simple, with just a knob, outlet and fuse, all for $30.00. I don't really need a temp gauge or timer, just a way to regulate power. I do like the way that shiny box looks though.

sorry no pics yet.

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"Preoccupation with an effect gives it power and enhances the error"
from "Your Owner's Manual" by Burt Hotchkiss.

No, but then I do not NEED a heat blanket either and could easily resaw with a bow saw if I wanted to, but I choose not to. I am pretty sure that a PID will control temp a lot more accurately than a router speed control all though both work fine, but then so too does simply pulling the plug out of the wall when it all smells and sounds right. But good wood is expensive and the stuff required to give a little more insurance was cheap enough to justify the effort. Si I am happy and that is all that really matters in my world.

Cheers

Kim

There are some good threads here on PID controllers...bought this one off of Ebay for about 30 bucks the 20 amp ssr was around 15 cheap mechanical timer I had but sells for around 10 bucks at Lowes...Balnket plugs ito the outlet...works fanatastic , built into base of bender..

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MK5acoustics.com

That looks to be a good unit though with a little searching you can get controllers for less, but the 12 amp relay is a great feature. Before retirement I was a control system electrician in a auto plant paint shop and dealt with temperature controllers all the time and they are really quite durable and last forever.

I picked up a cheap unit on ebay for about 1/4 of that price with an internal relay that works great, it is harder to find a high current relay unit but they are out there. These units are over kill for our usage but are a lot safer than the watch the temperature and turn on and of manually methods that we usually use. I use mine in on/off control mode so the PID loop is not even used and the 5 amp at 250 volt output it has is enough capacity at 120 volt operation. My only advice is to find a thermocouple with a long thin probe that will be easy to fit between the blanket and slat, most units come with a screw in type couple. Mine came with a fat probe but for $10 I was able to get a better probe.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

ON my thermocouple I cut the end off and twisted the wires together as Fred suggested in one of the threads...works perfect...

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MK5acoustics.com

I bought my blanket from MEI and ordered it with an embedded thermocouple so its actually 'in' the silicone of the blanket itself.

Cheers

Kim

Awesome, I'll look on ebay, I already have a 20amp inline timer switch so yeah this is just to make life easier. Any particular one to look for on ebay?
A lot of them have only 3 amp output load? Do I definitely need at least 5 amps?

Either 5 amps or more or pick up a relay to add to the mix. The twisted wires on the thermocouple wire work fine but I came upon a 1/8" diameter probe on ebay and it is easier to slip into the stack. I just kept searching and checking output current specs until I found one. I made a simple box and mounted the controller a timer and a duplex receptacle in it.

Here is a thread from the past that I started http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=19892

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

It's the relay that usually fails in a system like this. For that reason I built ovens and other heating systems from the basic components....a microprocessor, a thermocouple, and a relay. But the stuff I made was in service all day, every day....so.....this will probably work fine for you.

I'd recommend an eyelet type J thermocouple over simply twisting the wires together though. Twisting the wires together can work but the cost difference between thermocouple wire, which you need anyway, and a complete thermocouple isn't going to be worth challenging the possible number of variables that could foul you up here.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

Thanks everyone! The link Fred gave was great and I think I'm ready to venture forth. I'll be wiring it up to a 10A SSR so that shouldn't be an issue. Wish me luck!

Alrighty, I got a really good deal on this controller and I thought I had it all worked out but I think I'm stumped again! The listing said it was rated at 5A at 240v but it doesn't look like it... but I don't have to worry about that if I wire in a separate 10A SSR right? Does it go to posts 7&8?

Sorry, I'm pretty novice when it comes to technical electrical stuff. I was going off of Alans diagram in the other thread but of course I have a different controller.
Thanks!

Here is a pic of the side of my controller...

http://www.lmii.com/CartTwo/thirdproducts.asp?NameProdHeader=Heating+Blankets+and+Accessories

Anyone tried this LMI thermocouple? Seems reasonable at ten bucks.
I've used a leaf type thermocouple but it has to be kept in good contact within the sandwich.
Never had much luck with a round probe as they're usually at least 1/8" diameter. Never a good place to stick them in the sandwich at least in my experience.
Nelson

This is what I got and it's a real good price too.
http://www.auberins.com/index.php?main_page=product_info&cPath=3&products_id=144
I also got the K-type panel connectors so I can unplug it from my home-made box.

AJ
OUT2 is 1A @ 240V which probably won't heat a blanket very much,so you'll have to go through the SSR. Usually the output to the SSR is very small like 40 mA. In this case the SSR is just a switch controlled by the PID. you'll have to have 240V going in and out of the SSR, and the PID will open and close it accordingly to maintain the temperature.

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Matt Jacobs

"Don't tase me bro"

Hopefully Fred will chime in sometime, but I only have 120v in the shop so I come in with 120v on posts 10/9, out to a 10A SSR on posts 8/7 and then from the SSR feed the Blanket and my thermocouple (K-type) goes in 3/2?

Thanks for all the help guys...

Can you scan the manual and email it to me fred-tellier@cogeco.ca if I get a look at it I will have a better idea what you have and how to best use it.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

Helpful post. Thanks, guys.

Ed

After looking at the manual AJ emailed me I see something that can be a problem. His unit does not have an on off control mode only pid. PID is overkill and will probably hinder our used as it will slow down the heating of the wood which will probably hurt the bending process. The idea of PID is it ramps up the output at a controlled rate which is programmed by the PID values until it reaches the setpoint ( the relay will switch on and off as controlled by the PID to control the ramp up ), while on off control just provides full output ( relay closed ) until the setpoint is reached then it will switch on and off as needed to maintain the set temperature, I get a range of couple degrees over and undershoot around the setpoint.

I hope I have not added to the confusion

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

First of all, thanks very much Fred for all your help. I was able to talk to someone and I got my head around it will have it wired up in the next few days. Actually it does have a On/Off function, it's just buried in there amongst all the parameters. I will be definitely running it as On/Off and hopefully it all works as planned!

AJ that's good news as that is a real good controller Chromolox makes high end heating equipment

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866