First test run. How'd I do?


 
K

Ken B

New member
My "pit" is a ceramic Primo Oval XL and I'm using a just printed MicroDamper. I decided to try a test of 4 temperatures (200, 225, 275, 350) to see how the system behaved. PID settings were 4, 0.004, 5. Min fan 0% max fan 80%. No fan at 15%.

I'm really impressed, basically blown away.

Here are some of my observations. After lighting one spot with my MAP torch, it reached the target of 200° and stabilized in 10 minutes - wow. Each transition was smooth with some slight oscillation partially due to my changing the top vent. For the 350° segment, I might open the top vent even more.

Basically, the over and undershoots were never more than 5°. That's impressive. Here are the charts.

image_zps9udaywtl.jpeg


And with fan speed

image_zpsyqglro4i.jpeg
 
Last edited:
I can't wait to fire mine up first thing in the morning. Hopefully the rain in FL is gone by then. The graphs look good!! Did you have any of the heat deflectors in place?
 
If the max fan speed was set to 80% why is it showing 100% on the graph?
I might not even sleep tonight. I just want to go and fill my Primo up and toy around.
 
Ken B. That's a good looking first run. You can see that it want to oscillate toward the end. Try running it next time with your I set to 0.003. I find that 0.0035 is good on my Akorn and a Primo is a more efficient machine. I wouldn't be suprised if you had to drop I down to 0.0025 or possibly even 0.002. Start off at 0.003 though and see how things go.

EDIT: Just noticed you said you were playing around with your exhaust.. that could cause the oscillation as well. Still I think a lower I is more appropriate for your pit.

Russ Oz said:
Gotcha. So if max was set to 30% it would still show 100 on the graph (if indeed the fan was running at 30%).
Click to expand...

That's correct.
 
Last edited:
SteveCK said:
Still I think a lower I is more appropriate for your pit.
Click to expand...

Thanks, I'll definitely play with the I values. I normally stick to the 200° to 275° range for longer cooks but I can see that stabilizing it more over a larger range would be desirable.

And thanks again for the MicroDamper design. I'm sure that it will be perfect for my situation.
 
SteveCK said:
Ken B. That's a good looking first run. You can see that it want to oscillate toward the end. Try running it next time with your I set to 0.003. I find that 0.0035 is good on my Akorn and a Primo is a more efficient machine. I wouldn't be suprised if you had to drop I down to 0.0025 or possibly even 0.002. Start off at 0.003 though and see how things go.

EDIT: Just noticed you said you were playing around with your exhaust.. that could cause the oscillation as well. Still I think a lower I is more appropriate for your pit.



That's correct.
Click to expand...

In English, what exactly does I do? Mine was set at .008 on my test run. I'm also cooking on a Primo.
 
Russ Oz said:
In English, what exactly does I do? Mine was set at .008 on my test run. I'm also cooking on a Primo.
Click to expand...

My quick run down on PID for pits. The P is relative to the size of your pit. The I is your driving force. D is how badly you want the pit to freak out to changes.

I think I read somewhere that you are using something different than the MicroDamper so these values may not apply to you due to the differences of air delivery.
 
SteveCK said:
My quick run down on PID for pits. The P is relative to the size of your pit. The I is your driving force. D is how badly you want the pit to freak out to changes.

I think I read somewhere that you are using something different than the MicroDamper so these values may not apply to you due to the differences of air delivery.
Click to expand...

I'm using a RD3 on a Primo round. My settings were:
P: 3
I: .003
D: 6
Fan on above: 35%
Fan Min: 0%
Fan Max: 60%
Fan Start Up Max: 100%

That seemed to run very smooth for me. I'm very new to this so if anyone sees something that I should tweak please chime in. I wish it were easier to attach a pic. Does this forum not have an app??
 
You must log in or register to reply here.

 

Back
Top