Thermostat questions

[decepticron]

Thanks for the detailed explanation of the pid, really cleared things up. I am currently building a fridge smoker and think i will use a pid. On the bradley site they said you need to account for the mass of the meat for the autotune to calibrate properly. One guy did this by placing a large bowl of water in the smoker during the warm up. If this is true would you not also have to account for the temperature change outside the smoker during the time you are smoking. Up in these mountains the temp can change a lot in a day.

 

[cheech]

While the amount of meat in the smoker will throw off how the PID controller works I have found that even if I am off by a few degrees it is not a big deal. Normally I autotune going into winter and then again late spring. To autotune a controller is not a big deal to do just clicking a few buttons. It is just not a big deal whether I do or not.
I control by refrigerator smoker with in 1 degree if it varies to far from that then I will autotune again

 

[dan dan the meat man]

I have found new PID controllers on eBay for around $30 and depending on the type of smoking you do I have bought one with 10 ramp and soak cycles for $90. I use the single one as a relay to power up the multi ramp / soak with the meat as an input temp. The multi controls the box (frig) temp and when meat is up to temp it shuts itself off. Works great for summer sausage, turkeys and jerky.

 

[earache_my_eye]

I just did a search on ebay for a PID controller......TWO PAGES FULL!!

Looks like they're easy enough to come by.....now I just need more research so I can understand how to make it work for me......

Eric