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Unread 10-04-2011, 09:52 AM   #7
Billie
Got Wood.
 
Join Date: 09-20-11
Location: Belgium - Limburg
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Quote:
Originally Posted by Pappy View Post
Wow! It's like your talking French. I did understand any of it, but I looks great. Good job.
Thanks. It actually Dutch. :)

Quote:
Originally Posted by IamMadMan View Post
Whats the value of the resistor between points A and B? and what wattage (1/2 or 1)?
That's a K-Type Thermocouple

Quote:
Originally Posted by rksylves View Post
My problem with using a controller such as you've decided on is that the fan is either 100% on or 100% off. When the fan is fully on it will blow a huge amount of air into the cooker until it reaches the target temperature. The problem is that after the fan turns off the temperature will continue to climb. The temperature swings will be very wide. I found that turning the fan on by varying degrees worked best.
Hey Russ,

First of all thanks for the nice comment :)

Actually that's what a PID does...It calculates the time it takes to get to a certain temperature. The first time it will overshoot, the next time a little bit less and the third time it will stay at the set temperature. When the PID notices that the temperature is dropping it will activate for a few seconds. If you like the theory behind a PID see the wiki. ;)
I got mine tweaked (autolearn modus of the unit) to 0.2C (0.36F correct me if i'm wrong) offset... Which means that if i set my temperature to 230F (110C) it doesn't go above 230.36F (110,2C) and below 229.64F (109,8C)

Which is just fine by me ;)

Oh and in the schematic there's a potentiometer in the circuit of the fan. So i could change the speed of the fan if necessary. The only thing is i think 100ohm isn't enough, because that one burned out on the first try. So mine is built with the potentiometer, but it isn't connected any more...


Greetings
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OTP 22.5". Mini Smoker. 16" Cheapo Offset smoker. 22'' Selfmade TDS. DIY PID Controller
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