Modulating Auto Draw-off

[BRL]

Good Morning, I am just finishing up my modulating auto drawoff using a 4-20ma PID controller and a belimo actuator. Any interest in a parts list and wiring diagram? It can be built for $350-400.

[Polaris1]

Yes I'd like to see some info on it. Thanks

[BRL]

Valve $47
https://www.brewershardware.com/TC15VBFVPT.html?category_id=274

PID Controller $62
https://www.auberins.com/index.php?main_page=product_info&cPath=1&products_id=651

Temp Sensor $32
https://www.auberins.com/index.php?main_page=product_info&cPath=20_15&products_id=107

Modulating Actuator $165
https://www.supplyhouse.com/Belimo-LMCB24-SR-T-Non-Spring-Return-Proportional-Damper-Control-Actuator-Direct-Coupled-w-Screw-Terminal-Strip-24-VAC-DC-No-Aux-Switch?gclid=Cj0KCQiA7OnxBRCNARIsAIW53B9WSZYPMVOzp yClm-Nbvb428o0tmy-EaSNMkDXsrjCszZXbdT5K6QcaAvf6EALw_wcB

Resistor for 4-20Ma $10
https://www.supplyhouse.com/Belimo-ZG-R01-Resistor-for-4-to-20-mA-Conversions-500-Ohm

[BRL]

Wiring with a hand/off/auto switch
20696

[sirhart1]

Any chance you can get a better picture of your wiring diagram?

[BRL]

Sirhart1- I'll draw it up on Autocad and repost it when I get a chance. At the end of the season I can do a more detailed write up with pictures also. Any chance you snap some pictures of your steamaway inside and out. I think thats going to be our next years project. Thanks

[BRL]

Hopefully this is better

20762

[DougM]

Nice, any way you could attach the .dwg file? :)

[sirhart1]

BRL its a Leader Enhanced Steam away. I could take pictures in the spring if that is ok? also the drawing is small. fire145@cox.net if you'd email me a copy thanks

[BRL]

Sirhart1 spring would be perfect! Doug what version of autocad do you need it saved in? It's saved to 2020 right now.

[DougM]

2020 would be great, thanks. If there's no easy way to post it you can send it to me at eskimoin@gmail.com
Thanks!

[BRL]

Here is a little video of the first draw off. Still need to learn a bit and I should probably run it through auto tune but it works!

https://www.youtube.com/watch?v=KRfbdrPbHCQ

[wmick]

Here is a little video of the first draw off. Still need to learn a bit and I should probably run it through auto tune but it works!

https://www.youtube.com/watch?v=KRfbdrPbHCQ

Id be very interested to hear about your progress.... and how you've programmed the PID.. I've been daydreaming about building one of these recently.... Trying to decide between PID and a simple on-off. My only experience with PID controllers was on a plastic extruder...(running valves for cooling lines and electric heaters) From what I remember, it worked very well when things were running consistently... but if there was an unusual change in the process, EG. stopped the extruder for a few minutes to do a screen-change, etc... (which would eliminate friction heat for a time),,, it would over-cool and take a long time for the controller to get things figured out again... Could be that we just didn't have things programmed properly?? I've been wondering if an auto draw off would have the same sort of issues if I was late with loading wood, etc... Thanks for the update... I look forward to more...

[sam2145871]

Any updates on this? It would be great if you could post some more pictures and the wire schematic is very fuzzy. If you wouldn’t mind emailing me the schematic in a larger former I would appreciate it! My email is sam2145871@hotmail.com. Thank you!

***Edit- I also forgot to ask exactly which PID did you buy? There are three choices and I’m not sure if the RS-485 communication or the SSR features are useful or needed for this. Thanks again.

Marcus

[BRL]

Hey Marcus, the model is SYL-2381-mA. Should be the first option in the drop down menu. I'll send you some info when I get a second.

[JPGraphX2]

Hello, Could you give us PID parameters ? Thanks!!

[Bricklayer]

What did you end up using for a bracket to secure the valve actuator ? And did you have to get an extension for the butterfly valve shaft ?

[Bricklayer]

Been working on changing my auto draw to a modulating auto draw.
I’ve pretty much got it done. Just waiting on a couple parts to arrive.
I went with the belimo actuator and butterfly valve but if one wanted to save money you could buy a motorized ball valve on Amazon. (5 wire ) and the auber PID will still operate it the same as a belimo.
One good thing about the motorized ball valves is that they have capacitor return. The belimo valve is a fail in place actuator. So if you lost power while drawing off. Your valve would stay open and not close untill power was restored.

[bmbmkr]

Bricklayer,

How did you attach the Belimo valve to the butterfly valve? I have butterfly valves connecting my flue pan to dyrup pans, but you have to pull the lever out to turn them. I'm sure they make a butterfly valve without the lever lock, and I saw you asked the same question to the OP. I am diving into this project this year. I appreciate any info.

[Bricklayer]

I had to take the valve to a machine shop and get them to weld the handle in the pulled out position and then weld an extension on top of the valve handle for the belimo to attach to.
I could not for the life of me figure out a way to attach the belimo to the valve. So I ordered the bracket from CDL that bolts right to the valve. Was like $60. Havnt had time to put it all together yet. Going to be my fall/winter project.

[bmbmkr]

Thank you for the reply. Good info. The bracket keeps the Belimo in place so that it doesn't just spin around while trying to open the valve?


BW

[Bricklayer]

Yes. It connects to the bottom of the belimo and bolts to the valve.

[bmbmkr]

Yes. It connects to the bottom of the belimo and bolts to the valve.

Good deal, if you get a chance, could I get a photo or link when you get a chance?

[JPGraphX2]

Anyone could share PID parameters? :)

Thanks
JP

[Bricklayer]

For some reason I can’t post pictures. Is the site not allowing pictures to be attached to posts anymore ? I have a wiring diagram that I have been trying to post.

Here are the parameters that should work.
I have not had the time to fully test mine on the evaporator yet but it seems to work and modulate the valve.

INTY = P100
OUTY = 1
COTY = 4-20 ma
RD = 1 ( cooling )
OT = 2
HY = 0.1 ( this means it will go .1 degrees higher then your set temperature before it starts to open valve )

[Bricklayer]

Finally I’ve been able to get it all set up and put together 100%.
Noticed a few problems with this setup.
There are 1000’s of different settings on this PID but it seems like for what we want to do with it there isn’t an optimum setting without using autotune while making syrup. The PID is basically trying to keep your temp at your drawnoff temp. It calculates how long it takes to heat, cool down , and tons of other things while the evap is running and temp is fluctuating up and down. So if it sees a temp spike say when your heating it up to temp it may open the valve a bit to slow down the temp rise and test how the system will react. Can’t turn that off in settings.
I’ve dialed in the settings very close to where they need to be. But I think to be able to dial it in properly it needs to be run on an evaporator that’s boiling sap and making syrup and Auto tuned to that
I’m just testing it on the evaporator with water. So it’s not giving the same results as sap would. And every evaporator is different on how the temp drops in the syrup pan once a bunch of syrup is drawn off. The goal with a modulating valve is to slowly modulate the valve to keep the temp as close to drawnoff temp as possible and not spike to high. And also you don’t want the valve to open to 100% to fast and drawnoff all the syrup and flood the pan with fresh sap from the flue pan and drop temp way down. Then your basically batch boiling in your syrup pan.
The settings I have now with boiling water will start to open valve at the set temp. Then open it as the temp rises a bit but it won’t start to close untill the temp is below the drawnoff temp. So the temp of the syrup pan will drop way down and a bunch of not syrup will be drawn off. So just trying to get that setting right.
I think some of it has to do with the belimo valve speed of opening and closing being pretty slow. So just gotta figure out the closing settings on the PID. I’ve adjusted my belimo to only open about 3/4 of the way. So the actual time the valve takes to open and close is reduced. I also adjusted the butterfly valve and the belimo to be not fully closed 100%. Just enough to stop the flow of water while it’s boiling. Hard. This decreases the time the valve takes to open by about 5-6 seconds. It’s adjustable by the screw stops on the belimo valve. Basically the butterfly flapper is hitting the gasket but not that final pop to seat it in the middle of the gasket. Obviously this is going to differ with every valve. So that would need to be adjusted for whatever evap your using it on.

[cbmapleguy]

Hi, Do you have a better quality picture of the wiring? I built an auto drawoff a few yrs ago but looking to add a modulating valve to it.

Cheers!