How close are your temps with Auber PID?

[awarner322]

Hey guys, I have done a handful of beers on my herms system and have been tweeking things as I go. My question is: How 'close' does your system keep your temps to your set value? Mine never seems to settle on the number (overshoots, undershoot, repeat). What I don't know if that is normal. I suspect the answer is no...and my P I D settings need tweeking. I have auto tuned numerous times and always get different values. I have seen some videos of guys PIDs and I see the 'output' light turning on and off very rapidly and frequently....I do NOT have this happening. Should I?

I know these questions get annoying....and this forum is littered with them. But I can never seem to find the answers I am looking for. So thanks for your help.

I use

Auber SYL 2342 for my Boil
Auber SWA 2451 for HLT

 

[augiedoggy]

Hey guys, I have done a handful of beers on my herms system and have been tweeking things as I go. My question is: How 'close' does your system keep your temps to your set value? Mine never seems to settle on the number (overshoots, undershoot, repeat). What I don't know if that is normal. I suspect the answer is no...and my P I D settings need tweeking. I have auto tuned numerous times and always get different values. I have seen some videos of guys PIDs and I see the 'output' light turning on and off very rapidly and frequently....I do NOT have this happening. Should I?

I know these questions get annoying....and this forum is littered with them. But I can never seem to find the answers I am looking for. So thanks for your help.

I use

Auber SYL 2342 for my Boil
Auber SWA 2451 for HLT

did you perform the autotune function with the same amount of liquid as your controling temps with when your using them?

 

[awarner322]

Yes. I have a truly simulated brew day (minus the grain...)

Even after the auto tune with said amount of water...if I let that cool down and run it as a normal function...I still have that problem. I had read that could be an issue so I eliminated that variable....

I just find it strange my system should be calling for continued output when it has exceeded the set value by 3-4 degrees.

 

[kal]

I don't have that issue.

My setup gets to the set temperature and then stabilizes/stays at that temp.

Maybe your auto-tune did not work correctly?

(That said, auto-tune is typically not required as our setups are "highly dampened" meaning that it takes a lot of time/power to make a change to the temp).

Is it happening on both PIDs? Is your thermometer temperature on the PID (the PV value) stable?

Kal

 

[jeremy2027]

On my system I use keggles for all three vessels. At first in the HLT my temperature would always overshoot by 2 degrees and would drive me crazy. I filled the HLT with 15 gallons of water covered it and started my pump to recirculate as I would on a normal brew day. I then set the temp to 155*F and started the autotune on my Auber 2352 PID. It took about 40 minutes to complete and now everything is on the money. The pulsing of the element is very slight just to maintain where before if the temp would be 156 or 157 the element would still stay on for 3-5 seconds when set at 155. I would give it another shot on the auto tune.

 

[mabrungard]

Using a PID in the boil is problematic when its in proportional mode. It needs to be in manual mode so that you can adjust the percentage of power you deliver to the element(s). A PID can work for a HLT, but you need for the HLT to be well-mixed so that the energy input is well-distributed into the mass of water. My HLT is not mixed excepting when I stir it or by the convection currents in the water. Either way, its far from ideal. I just accept that its not going to do a great job in creating the perfect temperature in the HLT.

I've long come to the conclusion that sparging water temperature is not really a major concern in brewing. The example I like to cite is that decoction mashing does not cause tannin extraction. That wort and grain is boiled!

The alkalinity of the sparging water and the gravity of the final runnings from the tun are more important. While I'm all about alkalinity and pH, I ultimately find that its the gravity of the final runnings that has the greatest impact on tannin and silicate extraction. I now limit my final runnings to 3 brix or higher to avoid extraction of those nasties. The common lore for stopping runoff is 2 brix. That didn't work for me. All of this is just to reinforce that the temp of your HLT water isn't critical to your brewing success.

 

[kal]

Using a PID in the boil is problematic when its in proportional mode. It needs to be in manual mode so that you can adjust the percentage of power you deliver to the element(s).

Correct. Use a PID in manual for the boil, in automatic to hold a specific temp. For what it's worth, with the huge increase in New England style IPAs and APAs, doing hop stands is getting more and more popular (that's where hops are steeped for long durations at specific temps after the boil). By using a PID in in the boil you can use manual during boiling to control the vigorousness of the boil, then switch to automatic to hold at 160-170-180F for 40-60-90 mins (or whatever).

A PID can work for a HLT, but you need for the HLT to be well-mixed so that the energy input is well-distributed into the mass of water.

Correct. I recommend recirculating the water with a pump. That's what I do:

My HLT is not mixed excepting when I stir it or by the convection currents in the water. Either way, its far from ideal. I just accept that its not going to do a great job in creating the perfect temperature in the HLT.
I've long come to the conclusion that sparging water temperature is not really a major concern in brewing. The example I like to cite is that decoction mashing does not cause tannin extraction. That wort and grain is boiled! The alkalinity of the sparging water and the gravity of the final runnings from the tun are more important.

Sure, but don't forget that many of us have HERMS setups so the HLT temperature is the mash temperature, and we want that to be accurate. When I mash I do this:

So two pumps are needed. The mash temperature holds very well, following the HLT temp. Here's an example with the HLT set to 149F, the mash follows:

A video of this in action with a 1.100 OG Russian Imperial Stout I brewed a couple of days ago mashed at 149F (the mash lid isn't usually off - only done for the video):

https://www.instagram.com/p/BK6Z4xjAgPI/?taken-by=theelectricbrewery

So for many of us HLT temp is very important. Not for the sparge water (I agree it's not critical) but for holding mash temp.

I agree 100% that sparge temp isn't overly critical. My sparge water starts at 168F and slowly cools throughout the 60-90 minute sparging process since I turned off the Hot Liquor Tank element. By the end of the sparge the mash will be about 20 degrees cooler. This is intentional. A lower temperature near the end of the sparge helps minimize tannin extraction from the grain husks when it is most likely to occur (the mash has less sugar and higher pH). By the end of sparging the mash has very little sugar left so the drop in heat does not affect the flow. I find this works extremely well and I don't concern myself with the gravity at the end of the runnings as the sparge water has already cooled off greatly. Lets me make ~3.5 to 4% very delicate/light lasting american lagers without worrying about excess tannin extraction. Added bonus is that I don't worry about dry firing the HLT heating element as the water level drops.

Kal

 

[awarner322]

Thanks for the input here guys.

Kal- A few questions since I have a system that my system is set up exactly like yours. My issue is that I cannot stabilize my system like you are able to in this example at 149 degrees.

1) What are your P I D settings on your HLT? I know its a lot different for every system but I want to know if I am in the ballpark

2) Is that your mash with return shooting the wort right out the top? I thought in your initial build you ran the hose to the bottom of the grain bed?

3) How often and for how long does your element fire?

 

[kal]

Thanks for the input here guys.

Kal- A few questions since I have a system that my system is set up exactly like yours. My issue is that I cannot stabilize my system like you are able to in this example at 149 degrees.

1) What are your P I D settings on your HLT? I know its a lot different for every system but I want to know if I am in the ballpark

Every system is indeed different so my settings would not matter. What I would ask you is these things that seem to make a difference for people who have issues:

- Are you using the same 7/8" OD tubing I recommend or the thinner walled 3/4" OD?

- Are you using the same center inlet March pump I recommend?

- Are you using the same Blichmann kettles and false bottom I recommend?

I've had a few people that have temperature offsets / stabilization issues that were using different components that were able to make their problems go away by using the parts I recommend. Hope this helps!

EDIT: I read back on your thread here and you're not using the same PIDs as I use to begin with so comparisons really are not possible.

2) Is that your mash with return shooting the wort right out the top? I thought in your initial build you ran the hose to the bottom of the grain bed?

No - the hose has always rested on top of the grain bed. For complete details see my brew day step by step guide: www.theelectricbrewery.com/brew-day-step-by-step
There are lots of videos and pictures that show exactly how I brew on my setup.

3) How often and for how long does your element fire?

This is not really a question that can be answered, and/or the answer isn't really going to help you: While heating up it fires continuously. While maintaining temperature it fires often enough and long enough to keep the temperature stable. It's not something you control. It does it for you. That's the whole point of a PID: To make it simple/easy to maintain temperature without the operator having to worry about having to manually tweak it.

I don't know what your setup's like but I would recommend resetting the PIDs to their default values and then doing an autotune per the PID manual. It should stabilize.

Kal

 

[augiedoggy]

Every system is indeed different so my settings would not matter. What I would ask you is these things that seem to make a difference for people who have issues:

- Are you using the same 7/8" OD tubing I recommend or the thinner walled 3/4" OD?

- Are you using the same center inlet March pump I recommend?

- Are you using the same Blichmann kettles and false bottom I recommend?

I've had a few people that have temperature offsets / stabilization issues that were using different components that were able to make their problems go away by using the parts I recommend. Hope this helps!

EDIT: I read back on your thread here and you're not using the same PIDs as I use to begin with so comparisons really are not possible.


No - the hose has always rested on top of the grain bed. For complete details see my brew day step by step guide: www.theelectricbrewery.com/brew-day-step-by-step
There are lots of videos and pictures that show exactly how I brew on my setup.


This is not really a question that can be answered, and/or the answer isn't really going to help you: While heating up it fires continuously. While maintaining temperature it fires often enough and long enough to keep the temperature stable. It's not something you control. It does it for you. That's the whole point of a PID: To make it simple/easy to maintain temperature without the operator having to worry about having to manually tweak it.

I don't know what your setup's like but I would recommend resetting the PIDs to their default values and then doing an autotune per the PID manual. It should stabilize.

Kal

While I understand the reasoning behind the thicker hose I fail to see what the brand of the kettle or the pump have to do with a pids ability to hold and maintain temps? Do you believe the kettle thickness is going to have that dramatic of an effect? or is this recommendation just because its the only system you have used and therefore endorse?

This is coming from someone using thin walled bargain bayou kettles and $18 dc pumps with no issues maintaining temps with my the mypin td4 pids im using.


Myself I would thing ambient temps where your brewing (say outside in the cold) would have more of an effect if any...
Also I autotuned my rims pid after a brewing session while I still had grain in the mash tun... I figured it was the best wast to simulate brewing conditions and the real load and reaction delay on the pid.

 

[kal]

While I understand the reasoning behind the thicker hose I fail to see what the brand of the kettle or the pump have to do with a pids ability to hold and maintain temps?

Good point. You're absolutely right - I misread the post to mean they were having issues getting the MLT temperature to match the HLT temperature. It's a common question I get and the questions/suggestions I made were what are the most likely culprits.

None of those have anything to do with getting a PID to stabilize. There may be an offset between MLT and HLT if you use different parts, but you should always be able to get the HLT PID to stabilize.

Sorry for the confusion!

Myself I would thing ambient temps where your brewing (say outside in the cold) would have more of an effect if any...

The PID should still be able to compensate and stabilize. If it's colder out the PID will just fire more often to keep the HLT temp stable.

Kal

 

[awarner322]

This is what I don't understand and can't figure out

 

[kal]

Try another auto-tune. I've seen cases where an auto-tune doesn't go right.

Kal

 

[geoffey]

Try another auto-tune. I've seen cases where an auto-tune doesn't go right.

Kal

I concur. I've recently had a similar issue with overshooting temps and an auto-tune fixed it.

 

[joebob296]

You can also read the manual. And manually change the P, I , and D settings. I would run auto tune and would constantly end up 5 degrees over my target temperature. Even after pb was corrected. After I started to manually adjust the PID settings. (depending on what was happening, and in communications with Auber) The end result was a PID that would not change 1 degree for a 90 minute mash.

 

[awarner322]

Yeah. I have tried playing with that manually. Admittedly, I do not have a great depth of knowledge with this type of equipment. Ill keep screwing around with it....it works okay right now. Multiple auto tunes have been done. Seems to produce very different P I D values every time. Makes me think that it may be function of my system. My temperature probe is reading the temp of the HLT as it is pumped out of the keg with a T and the probe sticking in that. Could this be a problem? Given its proximity to the element?

 

[geoffey]

You might just not have the right temp controller. The ones with "fuzzy logic" have worked better for me. I can't explain why, but it's been the case. I've tried a few different models. Are you using an SSR? Is it a three vessel system like a Kal Clone?

 

[jodell]

This is what I don't understand and can't figure out

For what it's worth, I also bought the mypin PID's, and while they work great now, it did take a few tries on autotune for them to function properly. I wish at the time I had just bought aubers, if nothing else just for the manufactures instructions, but after some research they are working just fine now. I am always within a degree of my setpoint

 

[awarner322]

You might just not have the right temp controller. The ones with "fuzzy logic" have worked better for me. I can't explain why, but it's been the case. I've tried a few different models. Are you using an SSR? Is it a three vessel system like a Kal Clone?

It is very similiar to Kals. I use:

Auber SYL 2342 for my Boil
Auber SWA 2451 for HLT

Ill probably try and reset everything to factory settings and try another autotune. Seems like I have done 10-20 of them already tho. My boil PID works awesome. Maybe I should just buy one of those and use that....

 

[LarMoeCur]

Hey guys, I have done a handful of beers on my herms system and have been tweeking things as I go. My question is: How 'close' does your system keep your temps to your set value? Mine never seems to settle on the number (overshoots, undershoot, repeat). What I don't know if that is normal. I suspect the answer is no...and my P I D settings need tweeking. I have auto tuned numerous times and always get different values. I have seen some videos of guys PIDs and I see the 'output' light turning on and off very rapidly and frequently....I do NOT have this happening. Should I?

I had the same exact problem. I ran the auto-tune two or three times. It did not help.

It turns out my issue was a poor connection. I'm no electrician so, my layman's take is that if your trying to tune the PID and a connection is weak the PID will send more current or higher %. Now when you're up and running on a brew day everything is nice and hot and your connection maybe better so it takes less current to hold temp but your PID doesn't know that. So, it sends the high current load but the connection is better so the element heats better and faster.

Like I said I'm a Layman so please correct me if I'm in left field. Fixing my connection fixed my over shooting problem. I now hold rock solid at set temps.

 

[kal]

Yeah. I have tried playing with that manually. Admittedly, I do not have a great depth of knowledge with this type of equipment. Ill keep screwing around with it....it works okay right now. Multiple auto tunes have been done. Seems to produce very different P I D values every time. Makes me think that it may be function of my system.

It could be, if the system is somewhat unstable. When you do an auto-tune the PID fires the element and then watches to see how the temperature it reads from the probe reacts to that element firing. It does this a few times to see what the reaction is like and then adjusts the P/I/D values accordingly. If things are different when you auto-tune than when in use you may get different results. For example:

- If you have less flow one moment than in another due to various reasons then this'll confuse the PID during auto-tune because the results won't be identical. In other words, while an auto-tune is running don't play with any ball valves, don't turn the pump on/off, etc/
- If you do the auto-tune with water but then have flow issues when you use grain the results may also be different too. I mill loose and don't have flow issues.
- If you use more water (mass) during the auto-tune than the typical batch then it may overshoot during a real batch.
- Likewise if you have electrical connection issues (i.e. the temp probe reads intermittently). That would just confuse the PID.

I like to auto-tune at the important mash temp (150-160 or so) and use water, but that works for me as I don't have any flow issues during mashing (false bottom/pumps/etc work great together). I also mill loose (close to 0.050" mill gap). You want a loose crush with recirculating setups. I also run the pumps 100%.

My temperature probe is reading the temp of the HLT as it is pumped out of the keg with a T and the probe sticking in that. Could this be a problem? Given its proximity to the element?

Shouldn't be, if flow is good. Good auto-tuning results is all about consistency. Also depends on the PID too I suppose. Aubers tend to work well. I hear more complaints about some of the really cheap ones (though Auber technically in my eye is a 'bargain/budget' PID). Even Aubers will sometimes give odd results with auto-tune, requiring a redo.

It's also important to remember that our recirculating systems are highly dampened: What that means is that it takes a long time for the system to change/react when heat is applied, so generally speaking over/under shoots should be pretty rare. I ran my setup for a few years without any issues using the default P/I/D settings without having any issues before I did an auto-tune. This is why in my brewery build instructions I recommend that people only try auto-tuning if they have issues.

You can also try setting the P/I/D values manually as some have mentioned but that can get confusing pretty fast.

Good luck!

Kal