Sooo, has anyone got the skinny on how to recalibrate an AI DigiM-2 mantle?
It didn’t come with a manual, and I’m guessing the answer isn’t actually in there anyway.
It’s overshooting by 15-20C which is ridiculous for a PID, so I’m reasonably certain there is a “work properly” button I can push.
Only this time it doesn’t appear to be flashing red like the easy ones do.
Any and all help appreciTed.
I’ve got the same mantle with the same issue. Mine will overshoot by up to 50c on occasion. If you find a fix, please share!
Just got off the phone with AI.
Still need to RTFM.
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Run the auto tune using the R/AT button.
Load flask, set temp.
Hold R/AT for 3sec.
Should get feed back.
Unit will overshoot as it learns, then give feed back that it is done.
Will update once I’ve performed said trick, or fine manual arrives in email.
It should work I have done it in the past using the same instructions… The key is to take your time when you retrain the PID. Its really annoying but worth the patience that it takes…
I had the same mantle with the same problems after all there auto tune this try that it went into the trash
In this case it may have helped.
Unfortunately one of the new minions grabbed the flask of crude I was using and started another run…about 5min before I was convinced I had a fix (not gonna blame them for grabbing it right as it hit temp) 
We’ll see when I try and bring it online next week.
Whatever instructions they gave you was wrong.
You need to load pump oil up in your boiling flask to perform the task. Beause it’s non reactive. Then pull vac to take all the water out and then do a auto tune. The auto tune isn’t actually what is making it over shoot. That’s the calibration. And you can’t do that on those mantles . The actual reason it might be over shooting is becusee you set the jumps too high.
Meaning when your at x temp and go up 20+30c at s time the outside of the mantle is getting sooooo hot to keep up with temp raising. See you press up temp but the core take a whole to reach it. By the time you reach th core temp the outside bowl is so much hotter it just keeps applying energy.
I have digital mantles that are accurate by 1/10th of a degree and will never over shoot.
This might be a calibration and tuning issue. It might also be user error.
Thank you for your vote of confidence.
Auto-tuned with crude in the flask. Mantle is behaving much better.
I can see tuning under vac with a non-volatile load being more accurate.
Was planning to tune under vac if the parameters derived at ambient looked to need adjustment.
@square_root_pharms probe in boiling flask…
I’m gonna give you user error.
At some point one of the dozens of previous users on this mantle unwittingly pushed the auto tune button and messed up the calibration…
But trying to tell me that even though AI’s tech support and a page from their manual posted up thread both tell me HOW to drop the PID into auto-tune mode, it simply can’t be done with these mantles, is ludicrous.
Non-volatile…but close enough I guess.
So what about the extra heat load when that which is in your boiling flask is actually boiling?
Is tuning without that evaporative cooling (by using a non-volatile flask loading) going to be as accurate as tuning with actual process fluid?!?
I mess around with arduino PID code from time to time. This one.
This code works best when calibration is done with the same material you plan on running in your process.
I’ve sold many of them. Rarely did a basic auto tune solve the issue. It took a few tries
I don’t believe that’s how those pids work. You are supposed to load a flask with oil, and go directly to 100 or say 150 and that will adjust the bias setting of the PID … When boiling it reads the differential from the probe and decides based on the PID settings how much power to give it.
@cyclopath did this solve your issue? I just started the process. About 90 minutes into it. What set temp did you use and how long did it take you?
I used 130C i believe, with decarbed crude and no vacuum. it absolutely reigned in the wild temp over-shoots. nobody has actually gotten to run it for distillation yet because bits keep breaking, and we seem to be perpetually just shy of two complete kits. but it hits and holds 150C for decarb quite reliably now.
took a long time. don’t think it was much more than and hr.
The only way to retrain the AI (Abote) Is to continue to run them under stable conditions. That’s how those PID systems work. You cannot initially calibrate the PID tune (loop) via Non-Decarbed crude. The decarboxylation process reeks havoc on those cheap AI machines during the Initial tune. It has to do with the thermal probe RTD(PT100) ability to accurately read the temperature of the material in the flasks. If I’m not mistaken those AI machines do not use a thermal couple for the probe. They use a 3wire RTD that is less responsive to thermal change than a more appropriately suited x-type thermocouple. I’m sure there is a very good reason why @spdking stopped selling these systems. Very on brand for across international though!
After I posted that it finished. I had acetone in the flask at atmosphere. 40c and it went through 2 “heat cycles” and called it good. It now is within 5-6°c on a 10° increase of mantle temp. I have yet to make a run, but will post updates as soon as I do later this week.
What’s your time Delta? That thermal response is still pretty poor for a standard PID loop.
