Electric Brewing Supply 30A BCS Giveaway!


Home Brew Forums > Home Brewing Beer > Automated Brewing Forum > Automated volume sensing idea/help
Reply
 
LinkBack Thread Tools
Old 12-14-2012, 02:18 AM   #11
Vesku
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2011
Location: Lievala, Kuusumu
Posts: 108
Liked 20 Times on 14 Posts
Likes Given: 9

Default

Yes it can, that's what I'm planning to do. And then use that info with the Arduino. Try "Wheatstone bridge" in the Google.

__________________
Vesku is offline
 
Reply With Quote Quick reply to this message
Old 12-14-2012, 03:58 AM   #12
matho
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jan 2012
Location: hazelbrook, New South Wales
Posts: 42
Liked 16 Times on 13 Posts
Likes Given: 6

Default

I use load cells out of a cheap electronic bathroom scales and use a single supply instumentation amp



R3 thru to R6 represents the load cells, I have adjusted the gain to give me 5v at 102.3 kg which gives me 100mL resolution on a 10 bit ADC. I have been using it on my HLT for a couple of years now and has worked well, my theory is that if you know how much water you put in you will be able to work out how much you will get out because losses are fairly static.

cheers steve

__________________
matho is offline
 
Reply With Quote Quick reply to this message
Old 12-14-2012, 01:51 PM   #13
ryan_george
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
Recipes 
 
Join Date: Jul 2009
Location: Fergus, Ontario
Posts: 223
Liked 21 Times on 15 Posts
Likes Given: 6

Default

I guess all of these load measurements are only good if you're dealing with straight water? Or if you know the SG of your wort....

__________________
ryan_george is offline
 
Reply With Quote Quick reply to this message
Old 12-14-2012, 02:06 PM   #14
passedpawn
Waste Allocation Load Lifter - Earth Class
HBT_MODERATOR.png
Feedback Score: 0 reviews
 
passedpawn's Avatar
Recipes 
 
Join Date: Apr 2009
Location: ☼ Clearwater, FL ☼
Posts: 19,286
Liked 3480 Times on 2154 Posts
Likes Given: 2990

Default

Best way is to submerse 2 parallel electrodes in there and measure the resistance (conductivity) between them. The electrodes could be sank into the kettle, or in a sight-gauge-like assembly outside the main volume.

The electronics to monitor doesn't need to be complex; a simple voltage divider would work.

Since the resistivity of the wort will change with recipe, etc, another pair could be used to normalize the depth measurement. This pair would be small, i.e., 1/4", and would provide a constant resistance value. This pair goes to the bottom of the tank and is wetted as soon as wort is introduced.

Use the ratio of the two electrode pairs to determine depth in any conductive fluid.

__________________
Hey goomba I love how you dance the rumba
But take some advice paisano learn-a how to mambo
If you're gonna be a square you ain't-a gonna go anywhere.
passedpawn is offline
 
Reply With Quote Quick reply to this message
Old 12-14-2012, 02:15 PM   #15
crazyirishman34
HBT_SUPPORTER.png
Feedback Score: 37 reviews
 
crazyirishman34's Avatar
Recipes 
 
Join Date: Aug 2010
Location: Newton, MA
Posts: 1,424
Liked 51 Times on 48 Posts
Likes Given: 87

Default

That seams like the most straight forward way of doing things but the electronics are way above my head.

__________________
crazyirishman34 is offline
 
Reply With Quote Quick reply to this message
Old 12-15-2012, 02:52 PM   #16
MrNatural
The Original, beware of imposters.
HBT_SUPPORTER.png
Feedback Score: 0 reviews
 
MrNatural's Avatar
Recipes 
 
Join Date: Dec 2010
Location: Elverta, CA
Posts: 426
Liked 60 Times on 33 Posts
Likes Given: 45

Default

Quote:
Originally Posted by Vesku View Post
Yes it can, that's what I'm planning to do. And then use that info with the Arduino. Try "Wheatstone bridge" in the Google.
Wow, damn near ancient technology

Quote:
Originally Posted by passedpawn View Post
Best way is to submerse 2 parallel electrodes in there and measure the resistance (conductivity) between them. The electrodes could be sank into the kettle, or in a sight-gauge-like assembly outside the main volume.

The electronics to monitor doesn't need to be complex; a simple voltage divider would work.

Since the resistivity of the wort will change with recipe, etc, another pair could be used to normalize the depth measurement. This pair would be small, i.e., 1/4", and would provide a constant resistance value. This pair goes to the bottom of the tank and is wetted as soon as wort is introduced.

Use the ratio of the two electrode pairs to determine depth in any conductive fluid.
I think I like this approach.

You could set the default resistance to the range of thermistors used by PIDs and calibrate/display the results as volume instead of temperature?

Are there modules/boards or any off-the-shelf solutions to bridge between electrodes and PID?

Guessing the electrodes would need to have some sort of native resistance for there to be an easily measurable change as level of submergence varies?

I'm wondering how much the linearity would be affected by differences in the conductivity of the fluid? Would it be tough to calibrate each use, especially as the chemistry of the wort changes during the mash, and whatever effect that has on conductivity?

Appreciate the input.

Dale
__________________

I come awake........with the gift for womankind.
You're still asleep.......but the gift don't seem to mind.
~Ian Dury

MrNatural is offline
 
Reply With Quote Quick reply to this message
Old 12-15-2012, 03:42 PM   #17
MrNatural
The Original, beware of imposters.
HBT_SUPPORTER.png
Feedback Score: 0 reviews
 
MrNatural's Avatar
Recipes 
 
Join Date: Dec 2010
Location: Elverta, CA
Posts: 426
Liked 60 Times on 33 Posts
Likes Given: 45

Default

Quote:
Originally Posted by matho View Post
I use load cells out of a cheap electronic bathroom scales and use a single supply instumentation amp



R3 thru to R6 represents the load cells, I have adjusted the gain to give me 5v at 102.3 kg which gives me 100mL resolution on a 10 bit ADC. I have been using it on my HLT for a couple of years now and has worked well, my theory is that if you know how much water you put in you will be able to work out how much you will get out because losses are fairly static.

cheers steve
Interesting. Do you have any pics of the physical setup? What is max load for the load cells?

Dale
__________________

I come awake........with the gift for womankind.
You're still asleep.......but the gift don't seem to mind.
~Ian Dury

MrNatural is offline
 
Reply With Quote Quick reply to this message
Old 12-15-2012, 04:12 PM   #18
passedpawn
Waste Allocation Load Lifter - Earth Class
HBT_MODERATOR.png
Feedback Score: 0 reviews
 
passedpawn's Avatar
Recipes 
 
Join Date: Apr 2009
Location: ☼ Clearwater, FL ☼
Posts: 19,286
Liked 3480 Times on 2154 Posts
Likes Given: 2990

Default

Quote:
Originally Posted by MrNatural View Post
Wow, damn near ancient technology


I think I like this approach.

You could set the default resistance to the range of thermistors used by PIDs and calibrate/display the results as volume instead of temperature?

Are there modules/boards or any off-the-shelf solutions to bridge between electrodes and PID?

Guessing the electrodes would need to have some sort of native resistance for there to be an easily measurable change as level of submergence varies?

I'm wondering how much the linearity would be affected by differences in the conductivity of the fluid? Would it be tough to calibrate each use, especially as the chemistry of the wort changes during the mash, and whatever effect that has on conductivity?

Appreciate the input.

Dale
It would be linear as long as the two rods were spaced evenly apart.

The second set of electrodes automatically calibrates to the conductivity of the fluid, so it's not a factor. That's why the ouput from this is a ration of Electrodes1 / Electrodes 2, where Electrodes 2 are small and the depth of the fluid doesn't affect them.
__________________
passedpawn is offline
 
Reply With Quote Quick reply to this message
Old 12-15-2012, 09:04 PM   #19
Vesku
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2011
Location: Lievala, Kuusumu
Posts: 108
Liked 20 Times on 14 Posts
Likes Given: 9

Default

Quote:
Originally Posted by MrNatural View Post
Interesting. Do you have any pics of the physical setup? What is max load for the load cells?

Dale
Do you see, there's that "Wheatstone Bridge" right there

Have anyone tried to build the 2 electrode system? I've seen some discussions about it, but they all measured capacitance rather than impedance. There was issues with heat affecting the readings. Also an AC current is needed for the measurement to avoid electrolytic corrosion.

If only a few different level indication are needed, here's a simple circuit that works: http://www.electronic-circuits-diagr...msimages/6.gif I didn't have LED's on mine, but send the info to the Arduino. I also had 3 CD4066's get more levels.
__________________
Vesku is offline
 
Reply With Quote Quick reply to this message
Old 12-17-2012, 06:13 AM   #20
Chowhound
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2012
Location: Beckville, TX
Posts: 3
Likes Given: 1

Default

If you just want on off control you could rig up some type of magnetic float in your sight glass that would pick up a read switch mounted on the outside of the sight glass, just slide the switch up and down the sight glass to set your level. You could have multiple switches for different levels, hi, low, hi-hi, low-low.

__________________
Chowhound 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
BCS Level Sensing OneHoppyGuy Automated Brewing Forum 9 06-22-2012 09:27 PM
DIY Automated bottling for under 100$ is it possible ? BeNNeS DIY Projects 17 01-20-2011 08:31 PM
For Sale - BCS-460 Automated controller NinjaJoe For Sale 5 06-14-2010 05:03 PM
Great Idea, Regular Idea, or Terrible Idea? BrewRI General Beer Discussion 25 04-23-2010 05:19 PM
Electricians: help me swap out an arc sensing circuit breaker Coastarine DIY Projects 14 08-16-2009 12:25 AM