Manual PID tuning oddities.

[BitterSipper]

I will disagree.

You gone and done it now, he doesn't like it when you do that.

P.S. I figured it was something like this when you said integral is there to bring down the overshoot.

 

[muhteeus]

You gone and done it now, he doesn't like it when you do that.

P.S. I figured it was something like this when you said integral is there to prevent overshoot.

All about application. Most of the loops I have tuned were inverse .

 

[BitterSipper]

All about application. Most of the loops I have tuned were inverse .

I was really confused for a bit, I was like, this guy seems to know his stuff, wait... what did he say that's completely backw..... ohhhhh.

 

[augiedoggy]

Oh, I'll be trying it! I just brew outdoors so the temps we've had make chilling very difficult through my frozen hoses, so it'll be at least a couple weeks until I can try it. And plus I'm a big wuss with the cold, haha.

Which I why I built my full electric brewery and brew in a spare bedroom Although today we are back in the positive numbers yea!!

Sunday we broke a record set in 1889 with the -7 temps at this time of year. Sometimes I wish the weather was pid controlled...I could go for a little overshooting normal feb temps right now...

 

[muhteeus]

I was really confused for a bit, I was like, this guy seems to know his stuff, wait... what did he say that's completely backw..... ohhhhh.

Haha thank you. I have only been in the biz for 5 years, and sometimes I get pushback and think I am wrong. Glad to hear confirmation I can learn SOMETHING .

Did OP ever get anything solved?

 

[BitterSipper]

Haha thank you. I have only been in the biz for 5 years, and sometimes I get pushback and think I am wrong. Glad to hear confirmation I can learn SOMETHING .

Did OP ever get anything solved?

Op is me, tungsten has a piggyback problem and is trying to steal my thread

(my reply to augiedoggy before explains it)

Wait, what problem are you talking about. The problem that created this thread was that my controller was choosing to heat past the SV even with I and D off, which is contrary to proper function.

I mean I can tell you setting I to 1 effects better control than the default 240, and in fact having I at 2 is even better (for me). But that's not the problem, the problem is this controller is making it impossible to go through the steps to manually tune it. I posted an example of that process in the first post (though I disagree a little with the suggestion on how to come to an initial proportional setting).

I can get the controller to hold around a degree by tuning both at once, but I know I can do better and improve the rise and settling time if it wasn't acting so retarded.

I don't think that by now anyone disagrees that under P only control, there should be no output past SV, yet I have two ta4s that both do it.

 

[schematix]

You can do an inverse PID you just end up with negative gains. It's not wrong as long as you are consistent, but it's not common for your off-the-shelf controllers.

 

[TungstenBeer]

Which I why I built my full electric brewery and brew in a spare bedroom Although today we are back in the positive numbers yea!!

Sunday we broke a record set in 1889 with the -7 temps at this time of year. Sometimes I wish the weather was pid controlled...I could go for a little overshooting normal feb temps right now...

Great call. I'll most likely be building a new house next year and will be designing the brewery into the house layout, but for now... it sucks.

Op is me, tungsten has a piggyback problem and is trying to steal my thread

Haha sorry - it really is the same problem, you've just fine-tuned what your problem is a little further.

 

[BitterSipper]

Haha sorry - it really is the same problem, you've just fine-tuned what your problem is a little further.

Not really, yours is just a problem of low settling rate, which is solved by adjustments. You have P and I on and if the settings are not optimal, what you described will, appropriately, happen. It's likely your problem will be adequately solved by mucking with the integral.

I don't mind you hijacking my thread though, its the two haughty, holier than thou dweebs who don't provide anything constructive while flinging thinly veiled insults that I mind.

 

[augiedoggy]

Great call. I'll most likely be building a new house next year and will be designing the brewery into the house layout, but for now... it sucks.



Haha sorry - it really is the same problem, you've just fine-tuned what your problem is a little further.

last off topic comment (I promise) I'm actually looking to buy another house in the fall and am actually looking for something on the Niagara wine trail so I can grow some of my own hops and eventually (a couple years away) operate a nanobrewery from an outbuilding on my property. Either way I need dedicated brew space!

 

[PlexVector]

last off topic comment (I promise) I'm actually looking to buy another house in the fall and am actually looking for something on the Niagara wine trail so I can grow some of my own hops and eventually (a couple years away) operate a nanobrewery from an outbuilding on my property. Either way I need dedicated brew space!

I was going to just click the "like post", but I was afraid it could be misconstrued that it was for the "last off topic comment..."; however it is for your nano-brewery endeavor. I hope your journey is successful!
Cheers.

 

[TungstenBeer]

Well I know it's been a while, and while this doesn't help the OP it might help others who have read this thread.

I am confirming that my issue of the TA4 overshooting was fixed by setting P=3 (default), I=1, and D=off. Thanks augie!