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Posted: Wed Dec 02, 2015 11:40 pm
by mammuth
Whatever. I like it. Its easy to build something with shops around the corner and money no object. But to do it full diy out of stuff you have laying around or you can get its another thing. Keep on your journey! :D

P.s. depending on the programming of your temp controller (switch cycle and hysteresis) you propably want to switch from relay to ssr. Not sure how long a relay survives permanent switching of 2kw or so.

Posted: Thu Dec 03, 2015 12:10 am
by motoman
mammuth wrote: P.s. depending on the programming of your temp controller (switch cycle and hysteresis) you probably want to switch from relay to ssr. Not sure how long a relay survives permanent switching of 2kw or so.
Yes, we decided to make ssr in order to have automatic temperature control.
The problem is that we still have not seen it in action. Hope it will work properly.

Posted: Thu Dec 03, 2015 1:53 am
by mammuth
I see a problem with your pt100 element. Its a little bit big (its a to- case, isnt it?). How do you plan to put it inside the sandwich?

Posted: Thu Dec 03, 2015 11:51 am
by motoman
mammuth wrote:I see a problem with your pt100 element. Its a little bit big (its a to- case, isnt it?). How do you plan to put it inside the sandwich?
We have two of them and probably we will put them somewhere near sidewall of snowboard between cassette. Or somewhere between aluminium sheets of upper and lower blanket. I do agree that is is a little bit big.

Posted: Thu Dec 03, 2015 12:14 pm
by mammuth
I think you can convert your controller to J-Type (or K-Type) sensor, which is very small. There are some interface chips especially for that. Should be no big deal if you program it by yourself

Posted: Thu Dec 03, 2015 12:31 pm
by motoman
mammuth wrote:I think you can convert your controller to J-Type (or K-Type) sensor, which is very small. There are some interface chips especially for that. Should be no big deal if you program it by yourself
appreciate your advice. I will look for that sensors in the market. Anyway we have to make our sensor cables longer, so we will have opportunity to put another sensors. But now I am a little confused if we will not find another types of sensors and where to put that we have now... we did not think about the size of indicators.

Posted: Thu Dec 03, 2015 12:35 pm
by mammuth
If you use a J-Type sensor all you need is J wires which you weld together at the tip (you can do that with a car battery). So you can make it as long as you wish and dia is 0.25mm or so. The only culprit, you need to use only this type of cable, you cannot extend it via a normal cable and if you want to use connectors in between you need special J-Type connector. Same for K-Type. Otherwise its quite cheap :)

Posted: Thu Dec 03, 2015 1:06 pm
by motoman
mammuth wrote:If you use a J-Type sensor all you need is J wires which you weld together at the tip (you can do that with a car battery).
You mean that welding of wires is done in order to connect sensor to wire?
Probably I have to read more about J type. Sensor seems pretty long...where to put it in sandwich?

Posted: Thu Dec 03, 2015 2:34 pm
by mammuth
J or K wire is based on a special metal. Before i try to explain it from memory look here:

https://en.wikipedia.org/wiki/Thermocouple

you just weld the end of the two cables (each wire is different metal imho) and this connection is your sensor :)

The smallest version looks like this:

http://at.rs-online.com/web/p/thermoelemente/6212142/

Just a cable with the ends welded together

As said, the cheapest version is to get this cables (10 meter roll or so, quite cheap), cut it to the length you need and weld the tip with help of a car battery (google it, there are some instructions/videos how to do).

To interface it to your controller you need a chip like that:

https://www.maximintegrated.com/en/prod ... 31855.html

You have to look which interface you need for your controller, from max you can get them with i2c, can,.... Also different sampling resolutions and so on.

This one is 8bit, 0.25 degrees resolution, 0..1024 degrees with spi interface: Thermocouple Amplifier Digital MAX6675

The only other piece you need is a capacitor.



Nice uh :)

Posted: Thu Dec 03, 2015 2:43 pm
by mammuth
The 6675 is eol.

The other one is around 7 Euros @ digikey. You have to search the datasheets which is avail and cheap.

https://para.maximintegrated.com/en/res ... 0Converter

Posted: Thu Dec 03, 2015 2:51 pm
by MadRussian
my remark about problem is not intended to you. If you read the board you should know what it's about.
There is no stupid questions and questions you asked me was not stupid and I never told you you're asking stupid questions. What I told you over six months ago and we'll repeated again right now... you should read this board.....what I told you it enough information out here to make skis/snowboards WITHOUT ASKING AMY QUESTIONS. what I told you at the time questions you are asked was discussed and explained recently and giving you a links to discussions apparently that wasn't enough

Nothing wrong asking questions. Wrong IMHO is expected others to do your homework

not intended to OP We need old MM back maybe even for short period of time lol

Posted: Thu Dec 03, 2015 9:01 pm
by MontuckyMadman
Ive had a severe brain injury which damaged my mean and angry brqin parts so now everything is just peachy and sunny all the time. Its like a frontal lobe lobotamy. U should try it.

Posted: Fri Dec 04, 2015 1:28 am
by mammuth
MontuckyMadman wrote:Ive had a severe brain injury which damaged my mean and angry brqin parts so now everything is just peachy and sunny all the time. Its like a frontal lobe lobotamy. U should try it.
Pls elaborate how to do it. Maybe a small wiki. Would like to try that asap :)

Posted: Fri Dec 04, 2015 4:06 am
by gav wa
Mad Russian, I think you are forgetting this is HIS Journal. His thread. He can write in it whatever he damn well feels like. If you don't like what he writes why are you reading his journal.

Posted: Mon Dec 07, 2015 2:49 pm
by motoman
Dear mammuth,
thank you for useful advice!! we will learn about that types of termocouples after we will test our present.