Spike Brewing 12.5 Conical Fermenter Giveaway - Enter Now!

Home Brew Forums > Home Brewing Beer > Electric Brewing > PID Autotune Offset

Reply
 
LinkBack Thread Tools
Old 08-21-2013, 09:35 PM   #1
Dgonza9
Feedback Score: 0 reviews
Recipes 
 
Join Date: May 2010
Location: Evanston, Illinois
Posts: 1,183
Liked 10 Times on 10 Posts

Default PID Autotune Offset

I recently figured out something about my PID that allowed me to autotune it much more precisely. I'm not sure if every PID has this feature, but if, like me, your PID tended to overshoot a degree or two after autotuning it, this might help.

It turns out my PID, Auberins Sy-2362 has a setting in one of the menus called the "atdu." This is an autotune offset setting and the default on my PID is 10. So whenever I went to autotune, the PID offset the set value by 10 degrees. If, like me, you typically tried to autotune by setting the set value to about five or ten degrees higher than the initial water temp, well, the PID will struggle to figure out the proper settings because of the atdu.

I used think that the trouble with my autotuning was that I always did it with just water, not grain and water which would have more mass. But I recently waited until after a brew day and then autotuned with the spent grain still in the mash tun. The result? I was still overshooting by a degree or two.

Eventually, I figured out the atdu offset and set it to zero. After autotuning, the system is spot on, mine maybe overshoots a tenth or two tenths of a degree, but I have it set to maximum accuracy and have the temp filter at zero. So it's pretty much right there.

On my PID, to get to the atdu I have to enter 0089 in the settings password. Yours may be different.

Anyway, I hope that helps anyone who, like me, was having trouble tuning their PID. Maybe I'm the last to know this, but it took me quite a while to figure out.

Cheers.

Dan

__________________
On Tap: Belgian Barrel Aged Barleywine, Da Yooper's Oatmeal Stout, Breakfast Stout, Hop Your Face Off IIPA, Catcher in the Rye Saison, "Wino-head" Nelsin Sauvin Gumballhead.

Bourbon Barrel Duchesse De Bourgnone
Kegged:

Fermenting English Mild

on Deck: Lager?
Dgonza9 is offline
 
Reply With Quote Quick reply to this message
Old 08-22-2013, 01:48 AM   #2
FredTheNuke
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2012
Location: Charlotte, NC
Posts: 630
Liked 54 Times on 45 Posts
Likes Given: 17

Default

Thanks! I've just got my RIMS controller running and am beginning the fun (with the probes in air I changed the setpoint to 3 degrees above air temp and it was pulsing the SSR output on and off every few seconds - not quite what I want).

__________________
FredTheNuke is offline
 
Reply With Quote Quick reply to this message
Old 08-22-2013, 04:54 AM   #3
Dgonza9
Feedback Score: 0 reviews
Recipes 
 
Join Date: May 2010
Location: Evanston, Illinois
Posts: 1,183
Liked 10 Times on 10 Posts

Default

Autotune works well if the atdu is set to zero first. Good luck. Post your results here.

__________________
On Tap: Belgian Barrel Aged Barleywine, Da Yooper's Oatmeal Stout, Breakfast Stout, Hop Your Face Off IIPA, Catcher in the Rye Saison, "Wino-head" Nelsin Sauvin Gumballhead.

Bourbon Barrel Duchesse De Bourgnone
Kegged:

Fermenting English Mild

on Deck: Lager?
Dgonza9 is offline
 
Reply With Quote Quick reply to this message
Reply


Quick Reply
Message:
Options
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Trouble with PID autotune movet22 Electric Brewing 11 01-09-2014 10:25 PM
PID Autotune Question Brewbien Electric Brewing 9 08-13-2013 10:41 AM
Alarm during autotune? Broham1 Electric Brewing 6 04-12-2013 03:10 PM
PID Autotune Goes to Boil Chugmaster Electric Brewing 6 03-07-2013 06:06 PM
To autotune or not? redman67 Electric Brewing 31 01-23-2011 01:26 AM