# Water Level Sensors



## benno1973 (23/3/09)

Just wondering how people with automated breweries are able to sense water levels? I understand it can be done using a capacitive approach, where the volume of water affects the conduction between two probes? Is this right?

I'd be interested in putting something together that can measure volume in my HLT and boil kettle using probes or the like. And yes, I can (and do) use a graduated measuring stick, but it's another step I'd like to take towards automating parts of my brewery. Ideally I'd like to be able to read the results into a computer via RS232 or something, but not sure what's involved with that

I have no background in electronics, and don't even understand the stuff, but I did manage to put together a tight arse stir plate, so simple things I can manage. And I'd like to learn, so if it's a simple project, I'd love to give it a go. I have a background in IT, but more in software development, which means I know nothing about hardware or the electronics side. I'd go nowhere near mains power, but small scale stuff (i.e. as long as I can't kill myself) I'd love to play around with.

I notice that Jaycar are selling this device which measures water levels in water tanks - not sure if this sort of thing might be appropriate as a starting point, but I'd like to be able to get a volume readout rather than just a high/med/low 'indicator' so I guess some tweaking would be required. But is that sort of thing possible?

Anyway, any suggestions welcome, whether it's links to other websites or whatever. I've had a look over Zizzle's brewbot thread, but I can't see where it mentions how the level probes are hooked up. I've googled it, but can't find any simple project on how to put something like this together. Maybe it's not simple, and that's fine too, but I thought I'd ask the question...


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## Offline (23/3/09)

You can get ultra sonic level sensors, Im not sure that they would work with boiling liquids

Another option would be scales; one litre of water weighs one kilogram


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## jonocarroll (23/3/09)

Offline said:


> Another option would be scales; one litre of water weighs one kilogram


Depending on how precise you want to get. 

Scales were my first thought too. Best way would be to just calibrate it properly - measure it empty, call that zero, add a known quantity of water and measure, repeat until full. Then do the same again when it's at temperature and see if it's different. Sometimes the simplest solutions are the best.


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## Supra-Jim (23/3/09)

If you're looking at automation, you're probably going to trasferring you liquid with a pump. Why not loose the level sensors and install a flow meter into the pipework?

:icon_cheers: SJ


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## benno1973 (23/3/09)

Supra-Jim said:


> If you're looking at automation, you're probably going to trasferring you liquid with a pump. Why not loose the level sensors and install a flow meter into the pipework?
> 
> :icon_cheers: SJ



Actually, it's currently a 3-tier gravity fed system. Not that I have anything against pumps, I just what currently works and I'm happy with it. A flow meter is an interesting idea, but I assume they're not cheap?

I thought about weight, but it's difficult to measure the weight of a ~50kg boil kettle with a flame underneath.


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## Supra-Jim (23/3/09)

A level sensor that can handle boiling bubbling liquid and measure the level as it changes in the tank (i.e. opposed to a switch that indicates once a particular/fixed level is reached) will not be cheap either. You would really need something that sit in the lid of your HLT and and a probe or sensor that descends down into your water, all the way. This will not be cheap.

Nothing wrong with a gravity fed system, was just making an assumption about your move towards automation.

:icon_cheers: SJ


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## newguy (23/3/09)

Flow meters (the ones I've been able to find) start at about $300-400 US. Omega Engineering have a wide variety. Load Star Sensors have a nice range of mass sensors and various hookup arrangements which allow you to use them in a hanging arrangement. Load Star Sensors. I'm not sure how much $ the mass sensors are worth.


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## jonocarroll (23/3/09)

Kaiser Soze said:


> I thought about weight, but it's difficult to measure the weight of a ~50kg boil kettle with a flame underneath.


My thoughts were to hang the HLT from the ceiling/with a support of some kind and connect something like this in-line. It's even got RS232 output.


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## kirem (23/3/09)

http://www.parallax.com/Store/Sensors/Obje...e%2cProductName

That could be the basis for a homebrew ultrasonic level detction and measurement.

they also have pressure sensors, I know they used to have a pressure sensors capable of more than 1.6lbs.


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## benno1973 (23/3/09)

QuantumBrewer said:


> My thoughts were to hang the HLT from the ceiling/with a support of some kind and connect something like this in-line. It's even got RS232 output.



Nice one! I brew outside, so I'd need an engine lifty thing (I'm not a mechanic either!  ) but great idea. Unfortunately it's $700, so a bit pricey for me...


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## mika (23/3/09)

Weighing everything with the burner included in the weight measurement would be the best way to go. They use Ultrasonic level sensors here, big ticket items, but some process engineers are not that keen on them, due to the moving surface (from other flows feeding in) affecting the accuracy of the reading. Differential pressure sensors seem to be the preferred option, though in a 30m3 tank, there's a fair bit of differential pressure from top to bottom. In a 50L pot, not so much. And I'm not sure what sort of temp they can withstand. If you're just wanting to know whether the pot is full or empty a simple float level switch is hard to beat.
Othwerwise maybe look at a float and guide within the vessel (I couldn't get it to work, though I didn't invest a lot of time) so that the sensor equipment can be kept away from the hot liquid and the such and use a resistive scale to measure volume. Much the way a fuel tank guage works in a car. Proximity sensors are fairly cheap as well, so perhaps a controller could be configured to 'count' tags on the float guide as the level changed.


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## newguy (23/3/09)

The parallax PING ultrasonic sensor probably wouldn't work long in a high humidity/high temp environment. I looked into ultrasonic and ruled it out because of the need for environmentally "hardened" models.

What about a pressure sensor? Imagine a tube with a pressure sensor at the top. The tube runs down the side of your vessel and stops just short of the bottom. As water fills the vessel, the air pressure in the tube climbs. Read the pressure and bingo, you have your liquid level. Pressure sensors come in all sorts of pressure ranges and are quite cheap.


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## benno1973 (23/3/09)

newguy said:


> What about a pressure sensor? Imagine a tube with a pressure sensor at the top. The tube runs down the side of your vessel and stops just short of the bottom. As water fills the vessel, the air pressure in the tube climbs. Read the pressure and bingo, you have your liquid level. Pressure sensors come in all sorts of pressure ranges and are quite cheap.



Great idea. Would that work over the range of temperatures from ambient to boiling?


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## newguy (23/3/09)

Kaiser Soze said:


> Great idea. Would that work over the range of temperatures from ambient to boiling?



It should. Pressure transducers are commonly constructed from SS. If the sensor isn't capable of handling steam, just extend the tube away from the vessel. That would allow the steam within the tube to cool without affecting the pressure reading.

I just had a quick look through my Digi-Key catalog and most pressure sensors are rated for at least 85C. Good enough for HLT and mash tuns.....also good enough for a kettle so long as the sensor is far enough away.


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## kirem (23/3/09)

newguy said:


> The parallax PING ultrasonic sensor probably wouldn't work long in a high humidity/high temp environment. I looked into ultrasonic and ruled it out because of the need for environmentally "hardened" models.



hence in my post I said the BASIS for a homebrewed solution.

I like your idea of an air pressure sensor. The seal to create the pressures could prove difficult to maintain and would need to be environmentally hardened


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## jonocarroll (23/3/09)

newguy said:


> What about a pressure sensor? Imagine a tube with a pressure sensor at the top. The tube runs down the side of your vessel and stops just short of the bottom. As water fills the vessel, the air pressure in the tube climbs. Read the pressure and bingo, you have your liquid level. Pressure sensors come in all sorts of pressure ranges and are quite cheap.


Along the same lines - what about instead of sealing the tube for pressure, have a float inside attached to a (not-too-heavy) pole coming out the top... you could put a slide-wire-potentiometer at the top, and measure the float level by proxy like that. Just a thought.


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## newguy (23/3/09)

I just ran some numbers. Unless there is something wrong with my calca, the pressure in the tube is too small to measure with a cheap pressure sensor for rather normal sized kettles/HLTs (approx 50 - 100cm deep). Which of course explains why I haven't seen a liquid level gauge like this before.... <_<

However if you put a piece of styrofoam (the float) at the bottom of the tank connected to the plunger on a syringe-like deal then you could kind of amplify the pressure and be able to use a standard pressure sensor to measure liquid level. The float doesn't have to be styrofoam - it could be an air filled copper or SS tube.


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## technocat (23/3/09)

Kaizer Sose: If you are just a little electronic savvy I can show you a method of water level detection you can make yourself just using two transistors, a SCR to drive a relay with its inherent diode. You would need to make up a probe using two wires in a thin tube sealed at one end with epoxy, and fix this to the top of whatever vessel you are filling. HLT maybe, all for the fraction of the cost of a commercial job. You would need a low voltage 12VDC supply probably from a plug pack capable of delivering up to half an amp.


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## benno1973 (23/3/09)

newguy said:


> However if you put a piece of styrofoam (the float) at the bottom of the tank connected to the plunger on a syringe-like deal then you could kind of amplify the pressure and be able to use a standard pressure sensor to measure liquid level. The float doesn't have to be styrofoam - it could be an air filled copper or SS tube.



Yeh, that's an option. I had a look on the Jaycar site, and found this, which (as you say) has temp compensation up to 85C. This was the kind of thing you were thinking of? And I guess you just make the tube long enough so that the float can rise from the bottom to the top of the vessel and provide a measurable pressure differential?



Beernut said:


> Kaizer Sose: If you are just a little electronic savvy I can show you a method of water level detection you can make yourself just using two transistors, a SCR to drive a relay with its inherent diode. You would need to make up a probe using two wires in a thin tube sealed at one end with epoxy, and fix this to the top of whatever vessel you are filling. HLT maybe, all for the fraction of the cost of a commercial job. You would need a low voltage 12VDC supply probably from a plug pack capable of delivering up to half an amp.



Beernut - this is exactly what I'm after. I am almost an electronic illiterate, but I'd be interested in learning how to do this. If you even had a circuit diagram or something, I'd be happy to go away and do a bit of research to see if I could work it out. Any help appreciated!


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## roger mellie (23/3/09)

Kaiser Soze said:


> Just wondering how people with automated breweries are able to sense water levels? I understand it can be done using a capacitive approach, where the volume of water affects the conduction between two probes? Is this right?
> 
> I'd be interested in putting something together that can measure volume in my HLT and boil kettle using probes or the like. And yes, I can (and do) use a graduated measuring stick, but it's another step I'd like to take towards automating parts of my brewery. Ideally I'd like to be able to read the results into a computer via RS232 or something, but not sure what's involved with that
> 
> ...



You wont find a cheap sensor - liquid level measurement is done in numerous ways - all quite expensive:

Differential Pressure - Transmitter would cost say 2K - accuracy comes into play when the difference is small
Ultrasonics/Guided Wave Radar - horrendously expensive - take a lot of setting up - dont like turgid surfaces - or steam.
Metal Tape - not cheap either - not suited to miniaturization
Float methods (where a metal float goes up an down a sight tube and inductive sensors detect the level) - you could make your own but inductive sensors arent cheap

I would discount flow measuring level and this is usually not accurate enough.

By far the simplest and cheapest way of simple (non adjustable) liquid measurement is 

http://uk.rs-online.com/web/search/searchB...t&R=0845976 they are available in Aus - I think mine cost me 23.00

I use these on a couple of other water tank automation projects I have around here (low level cutouts) - they are cheap - can handle boiling liquids.

I always thought that if I ever got round to building a brewery worthy of automating that I would use these - the automation side of level control in a 50L brewery is usually to fill up a vessel to a pre determined level then heat it. The analog reading of how much in the tank is immaterial - repeatability is paramount.

Thats my 2c anyway

RM


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## kirem (23/3/09)

Through calibration, I know how long to switch the solenoid on to get the volume I want. It is part of how I get my system to autostart whilst I am still sleeping or otherwise occupied;

http://www.aussiehomebrewer.com/forum/inde...st&p=433700

It is also possible to manually fill the HLT the night before with only the volume of water needed for dough in and empty that at a preset time. This is the technique I am trialling on the weekend;

One timer to start the mill motor and open the solenoid and turn it off some time later and another to start the mash cycle (pump and heat exchanger)

going a little OT;
The system ramps and soaks from 20degC to mash out using the heat exchanger, so there is no great importance on strike or sparge water temperature for me. My heat exchanger is quite efficient at changing mash temperatures and really negates the need for a HLT.

I don't see a problem with the mash returning to 60-70 deg during sparge and then recirculating to mash out temperature. The enzymes should be mostly denatured during the first mash out.


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## benno1973 (23/3/09)

newguy said:


> I just ran some numbers. Unless there is something wrong with my calca, the pressure in the tube is too small to measure with a cheap pressure sensor for rather normal sized kettles/HLTs (approx 50 - 100cm deep). Which of course explains why I haven't seen a liquid level gauge like this before.... <_<
> 
> However if you put a piece of styrofoam (the float) at the bottom of the tank connected to the plunger on a syringe-like deal then you could kind of amplify the pressure and be able to use a standard pressure sensor to measure liquid level. The float doesn't have to be styrofoam - it could be an air filled copper or SS tube.



Just found this which references the motorola pressure sensor from Jaycar.


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## benno1973 (23/3/09)

roger mellie said:


> You wont find a cheap sensor - liquid level measurement is done in numerous ways - all quite expensive:



I was hoping that wasn't the case!  



roger mellie said:


> I always thought that if I ever got round to building a brewery worthy of automating that I would use these - the automation side of level control in a 50L brewery is usually to fill up a vessel to a pre determined level then heat it. The analog reading of how much in the tank is immaterial - repeatability is paramount.



Although I'd like to fill to a certain level in the HLT, and then empty certain varying volumes into the mashtun, so a reading of how much was in the tank is essential...


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## kirem (23/3/09)

those float switches are what I use as an interlock so that I can't apply power to the element until they are covered with water and to autofill the HLT and heatexchanger.

http://www.jaycar.com.au/productView.asp?I...mp;form=KEYWORD

http://www.aussiehomebrewer.com/forum/inde...st&p=433736


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## Jono_w (23/3/09)

Hey guys,
This is what i found when trying various ways of measuring liquid levels in my system.

-Differential pressure sensors worked ok but had a lot of trouble with liquid getting into them and also at 50L you need a very sensitive sensor i think mine were mpx100 sensors which if i recall correctly they went to around 1psi, any variance in the temp of the water used to play havoc with these sensors also if you got a small amount of liquid in the air line the surface pressure of the water would hold pressure in the line and give false readings.

- Load Cell or scales are the way to go, search eBay for industrial scales with rs232, they can be had for around $200. These will give you an accurate measurement regardless of liquid temp , viscosity and resistance.

- Resistive. If you are doing the same size batch I would recommend this type. I use it in my 50L system. I have a stainless rod suspended from the top of the tank for high level and a insulated bolt in the bottom of each tank to show empty. These are wired to my USB IO controller and just register on or off, very stable and simple.

Cheers.
Jono


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## BusinessTime (23/3/09)

Can you fill the HLT, cut off the water source when the float kicks in then empty based on timings assuming you will have a consistent flow rate out of the tap at the bottom?.


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## benno1973 (23/3/09)

BusinessTime said:


> Can you fill the HLT, cut off the water source when the float kicks in then empty based on timings assuming you will have a consistent flow rate out of the tap at the bottom?.



I could, although a consistent flow rate would (I assume) require the valve fully open, which is fine for initially filling the mash tun, but not so good for sparging. For sparging I'd want to throttle back the flow.


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## roger mellie (23/3/09)

Kaiser Soze said:


> I was hoping that wasn't the case!
> 
> 
> 
> Although I'd like to fill to a certain level in the HLT, and then empty certain varying volumes into the mashtun, so a reading of how much was in the tank is essential...



Well - given that the head pressure wont change much - you should be able to do this based on time.

Fill to 50L - easy to replicate this using a 'cheap' float. Then based on a valve opening - which will have a fixed orofice and hence backpressure - will give you a fixed volume per minute/second open (within reason). Imperically you should be able to fine tune this to be quite accurate - especially if you use gravity as opposed a March Pump h34r: and the same hoses each time.

Johnathon is right - a gravometric based system would be very accurate - I still think given your earlier comment - that a switch and a valve and a timer are going to be easier to customise than trying to control based on a signal from a load cell. Bearing in mind unless you buy a head unit for the weight reading - therefore giving you the ability to tare and set inputs to your automation system based on weight setpoints - you are going to have to do some work at the component level to get this all going.

Level Switch/Timer/Valve - you wont get cheaper.

RM


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## matho (23/3/09)

there is a selection of level switches 
here http://www.temperature.com.au/Products/LevelSwitches.aspx
if that helps


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## newguy (23/3/09)

In terms of instrumentation this would be dead easy, but it would require another container.....

For automated filling of the HLT or mash tun, why not have a fill grant, similar to the outflow grant usually present between the mash tun and kettle in many commercial breweries? Make this fill grant about 1.5l in volume with a decent accuracy float switch or resistive float sensor at the 1l mark. Fill from the bottom until 1l is in the grant, then open a drain valve to dump the contents into the HLT/mash tun. Repeat x times to get x litres in the vessel.

It's a little more involved piping-wise but it's dead easy and very cheap.


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## Tony (23/3/09)

Without reading the whole post so forgive me if its been said.................

Ultrasonic level sensor in a strait sided vessel with a 4-20mA output to a display is what i plan when i can get my hands on one.

Span your range.... say for eg. 0 - 600mm to 0 - 50 liters.

easy.

Edit...... just had a think and this will be a bitch in my HLT with HERMS coils, temp probes and heat elements ect to provide false echos but in a vessel with clear view to the bottom......... perfect!


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## technocat (23/3/09)

what I had in mind was simple. When the water reaches the probe it pulls a small relay in which shuts your solenoid valve down. HLT is to the desired level probe can be adjusted up or down to suit. Regarding varying levels in MLT after looking at flow meters and some pretty expensive gear I settled for timing circuits to shut water flow off as well as gas. This idea was take from irrigation setups. I am working on this at the moment. I will draw up a circuit diagram of the former idea and post it here and if you are looking for a cheap timing device other than commercial irrigation ones I see in Jaycars cattle dog which I just received last week a little Micro driven timer which you could sub switches rather than jumpers to get different timing combinations Cat No. KC-5464 also see they have a water level sensor for eight bucks, circuit board with works would save cobbling my idea up on a tag strip. The output would probably power up a small minature relay to control your solenoid valve.
I even see a project there for a computer interface. Things are moving ahead with Jaycar.


Cheers


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## Fermented (23/3/09)

Sorry to go so low-tech, but I cooked up something like this a while back for a film processor's bleach dump overflow jerry can.

If it's for attended operation, get a couple of pieces of threaded SS rod and matching nuts. Mount either on a piece of SS bracket (with grommets to isolate the 'probes') or plexiglass / nylon / teflon / etc or through the non-conductive lid of the container. Two holes, threaded rod through and bolted into position. One higher than the other by say 20 mm. Tighten nuts. Affix terminals (or drill through the rod and wrap wires and use heat shrink tube for a nicer finish. Put a 9V battery and a small piezo siren in series (polarised) on one terminal and the other terminal returning to the 9V battery. The little piezo siren is annoyingly loud. Louder siren? Probably 12VDC, so use a plug pack instead of a battery. 

You can use the same arrangement without the siren and power it from a PLC and digital I/O card (used Siemens ones with software kit for making your own firmware go for a couple of hundred bucks these days, other kinds are around; old and slow is OK as this isn't a high speed process). If no software comes with it, then use your Google-fu to find something liek a back up copy somewhere  . The I/O on these is usually 24VDC. In software, it's like Port goes high then [other things happen]. Not overly hard. The development kit is a bit of a brain bender at first, but you can wrap your head around it after a few hours. 

Cheers - Fermented.


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## Sully (23/3/09)

Try Here for ideas.
The control unit is about US$40.00. Was looking at doing something similar before I changed to HERMS. 
Cheers
Sully


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## Guest Lurker (23/3/09)

Like Roger Mellie I work with these things for a living. Ultrasonic sensors and flow meters at the cheaper end would be the least reliable in my experience, mass is going to be the most reliable. But for the idea of a tube filling from the bottom and measuring the sealed in pressure, the more conventional way to operate it is as a bubbler ie 1) have a tube as described venting to the base of the vessel, 2) fill vessel with water, 3) with a hand pump or compressor pressurise the TOP of the tube, 3) reduce the air input until the tube is only slowly bubbling (tube is empty of water but no friction loss from air pumping and 4) have a pressure sensor in the tube with the appropriate range to measure exactly the height of water it is pushing against.


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## Crazy (23/3/09)

I got my design from when I was running a job installing a water bottling line at Coke a few years back. 

They have the resorces (Money) for all maner of fancy level transmitters that tell them exactly where the level in the vessel is. They use pressure, ultrsonic and capacitive systems for their analogue systems. 

The bit that supprised me was that their fail safe systems were simple and cheap sensors. The relay costs under $100 and the probes are stainless set-screws taped into a plastic bung that is in turn screwed into a standard stainless socket welded into the vessel. Another "earth" stud is welded to the vessel. 

This system works every time and can be set up fail safe for high or low level aplications or the relays I use can be used with three probes (one is the earth refrence) to cycle a pump or valve to keep the level between two points. This is perfect for control of the sparge valve when fly sparging.

Derrick


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## Zizzle (24/3/09)

Water and wort are excellent conductors. For my mind the conductance probe method is by far the most reliable and the cheapest too.

For my brewing I don't really need infinitely variable measurement down to the ml or even hundreds of ml. Strike and sparge volumes may need to vary a couple of litres tops around pre determined points.







Most micro controllers have multiplexers in front of the ADC so it is trivial to cut a range of probe lengths and hook them up. As you can see in the above I used a small plastic block with slots cut for 5 probes, but only ended up using 2. A single screw hold the probe so they are very easy to adjust.

I was actually thinking I would mark or notch the probes so that they didn't need to be clamped by the screw. I would then be able to tweak the desired levels accurately by hand when I loaded the grain. Just like reading a ruler. Actually that would probably we easier than keying in desired values via the controller. The only downside is that the exact values used would have to be recorded by hand.

The circuit is dead simple. Just connect the vessel to gnd and the probes pretty much straight to the ADC input on the micro. The Atmega has programmable pull up resistors so just turn them on in software. Sample the ADC and apply a simple threshold when you want to know the water levels. Too easy. From memory the resistance was about 20K ohm through water for reference.

I had non brewer mate who saw my setup and said "beauty you can do an automated system to top up my pool from my rain water tank". Same principle, just difference probe implementation. Works well despite the much harsher environment.

I also use a single probe in the kettle to ensure I never apply power to the elements without them being covered.






You can see I prototyped the probes with a rustic looking bit of wood with some holes in it for the probes:







Haha.... looking through my photo stream I see a couple of AHBers tries to demonstrate what they though was an effective "probe" system at a qld swap... dodgy bastards....


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## seravitae (24/3/09)

ultrasonics are actually danm cheap to use. in fact you could probably get away with a standard 40khz transducer, an AVR or PIC and a few hours if you're handy that way.



Alternatively it may be possible to use capacitive sensing, although I have heard the metal of the keg can interfere. I am sure there are ways around it though. Capacitance sensing is danm sensetive too if you need it to be, I was able to accuratly sense a fly buzzing on one side of a room


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## jonocarroll (24/3/09)

sera said:


> Capacitance sensing is danm sensetive too if you need it to be, I was able to accuratly sense a fly buzzing on one side of a room


I dare say that this seems even more sensitive, and apparently only $80. Okay, not sure how it works for this situation, but the link is worth the trouble.


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## seravitae (24/3/09)

Using laser isnt a bad idea - same way you make those long-range laser mics using modulation of the laser on a surface like glass.



Actually to take it a step further, I've read a report about some guys who managed to sense the cpu working (residual EMF) and managed to actually determine individual commands being executed on a remote CPU.





</offtopic>


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## Zwickel (25/3/09)

just my simple waterlevelsensor:


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## benno1973 (25/3/09)

Thanks for everyone posting so much useful information!

I hadn't (for some reason) ever thought about having adjustable conductance probes, and that's probably the simplest design I could get working easily. In fact, having multiple probes could mean that before brewing, I could set low volume levels in my HLT for mash in and each sparge stage (for batch sparging). As so many people have pointed out, the analog reading of how much in the tank is immaterial.

I'll post back if/when I get something up and running...


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## shmick (25/3/09)

Next part of the project...

What do people use for water solenoid valves?

Most of the ones I've seen are slave types which require pressure (more than gravity feed) to operate correctly. 

Any experience on what and where to get them?


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## benno1973 (25/3/09)

shmick said:


> Next part of the project...
> 
> What do people use for water solenoid valves?
> 
> ...



 Yeh, that was going to be my next question, but I didn't want ask too much in the one post!


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## Crazy (25/3/09)

My earler level probes were little kits for $20ish from jaycar which I can't find at the moment but then upgraded to the ones mentioned earllier. 

For valves I use standard 2 or three peice stainless valves and attach a wiper motor to the top. Positioning is then done using two proximity switches.

Cheers Derrick


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## Zwickel (25/3/09)

shmick said:


> Next part of the project...
> 
> What do people use for water solenoid valves?
> 
> ...



the water solenoid valve Im using is one from a washing mashine.



one can get very cheap at ebay.

Cheers :icon_cheers:


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## technocat (28/3/09)

Lost this thread for a while being up in the big smoke for the past week I dug these circuits out of my notes for a simple level sensor without being to complicated. Ah oh! complications "Upload failed. You are not permitted to upload this type of file".
Can anyone tell me why this occurs just trying to upload a couple of schematics. I had this happen with trying to upload recipes. Got me stuffed, enlighten me someone.

Cheers <_<


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## Thirsty Boy (28/3/09)

what about a remote site tube - with a ball floating in it - and a laser distance measurer pointed down the tube.

The laser does the measuring work and the tube with the ball keeps it away from the hot steamy wobbly bit, so it doesn't have to be an industrial unit and it doesn't have to deal with waves and splashes.

You'd get a readout that I'm sure some tech minded person could fudge into a control circuit

They use ultra sonics at work for standing tanks like HLT - working tanks like mash, lauter and kettle use flowmeters and simple empty/not empty sensors.

Both methods keep the instrument techs busy - they screw up frequently.

Surely today there would be a software solution... point a camera at a site tube with a bright orange ball floating on top - feed image into computer - write a bit of software that converts the position of the ball vs a scale, into a volume measurement - output into your brewing control software. If you could get all three vessels into the same camera shot.... thats all three volume measurements taken care of with the one bit of electronics and some code.


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## kirem (28/3/09)

Thirsty Boy said:


> what about a remote site tube - with a ball floating in it - and a laser distance measurer pointed down the tube.
> 
> The laser does the measuring work and the tube with the ball keeps it away from the hot steamy wobbly bit, so it doesn't have to be an industrial unit and it doesn't have to deal with waves and splashes.
> 
> ...



Exactly my thoughts the other night. I already have a tube to manually measure the water in the HLT so fitting ultrasonics to the top of the tube to measure a ball that is being floated up or down sounds like a great solution to me


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## Thirsty Boy (28/3/09)

Actually, it would be easy to get all three site tubes in the same camera shot - make them remote from the vessel. Small hoses convey liquid to remote site tubes mounted on the wall - camera pointed at the appropriate bit of wall. A $20 webcam would be good enough.


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## technocat (28/3/09)

Beernut said:


> Lost this thread for a while being up in the big smoke for the past week I dug these circuits out of my notes for a simple level sensor without being to complicated. Ah oh! complications "Upload failed. You are not permitted to upload this type of file".
> Can anyone tell me why this occurs just trying to upload a couple of schematics. I had this happen with trying to upload recipes. Got me stuffed, enlighten me someone.
> 
> Cheers <_<


 
Thanks to Newguy I reformatted these and got them on, thanks Mark. Unfortunately I wrote an essay underneath on how these circuits worked but looks like I lost the lot.


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## Tony (28/3/09)

I have used hundreds of these level relays in indistry and they work great. WOuld be perfect.

Use the metal of the HLT as the refference and raise or lower your probe to switch at your volume.

cheers

http://www.eqams.com.au/multitrode.htm


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## technocat (28/3/09)

Yeah Tony I described how to set up the probe in my description of these circuits and adjustable for different levels. What I was trying to do was KIS without being stupid, with a little knowledge of electronics and a 40 watt soldering iron, ideal working circuitry for the "home" brewer, I see you have a handle on what I was getting at. When I get a bit of time I will back it up with some useful info for people who might be interested. I don't know what happened to the text below the graphics it just didn't show up. :unsure: 

Cheers


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## technocat (28/3/09)

Kaiser Soze said:


> Thanks for everyone posting so much useful information!
> 
> I hadn't (for some reason) ever thought about having adjustable conductance probes, and that's probably the simplest design I could get working easily. In fact, having multiple probes could mean that before brewing, I could set low volume levels in my HLT for mash in and each sparge stage (for batch sparging). As so many people have pointed out, the analog reading of how much in the tank is immaterial.
> 
> I'll post back if/when I get something up and running...



I find a multiple timer, controlling a solenoid valve for water into the tun more useful. I guess everyone has their own approach that's what make this forum interesting.


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## Zwickel (28/3/09)

Tony said:


> Use the metal of the HLT as the refference and raise or lower your probe to switch at your volume.


Thats what Im doing :icon_cheers:


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## Tony (28/3/09)

Zwickel said:


> Thats what Im doing :icon_cheers:



great minds think alike mate


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## Zizzle (30/3/09)

Reading all the complicated schemes then reading Zwickel and Tony's posts made me reminds of me of the Cult of Done Manifesto.

"9. People without dirty hands are wrong. Doing something makes you right."

http://www.ikiw.org/2009/03/04/the-cult-of-done-manifesto/

But there is no Stop Energy here.
If you think your scheme will work, try it and let us know!


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## kirem (23/7/09)

http://www.siliconchip.com.au/cms/A_109529/article.html

http://www.jaycar.com.au/productView.asp?I...mp;form=KEYWORD

I wonder if this could be adapted to suit a HLT.


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## hockadays (23/7/09)

prob would work it depends on the sensitivity of the pressure instrument i'd say.


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## Screwtop (23/7/09)

Kirk, wonder if it can be calibrated to give volume????

Screwy


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## matho (23/7/09)

i have just bought some electronic bathroom scales from the reject shop for 20 dollars im going to use the presure sensors in a pic project to measure volume eventually but for the time being im just going to put it under my bucket 'o' death. i think the scales uses piezo restistive devices ill have to pull it apart to find out.

cheer's matho


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## kirem (23/7/09)

Screwtop said:


> Kirk, wonder if it can be calibrated to give volume????
> 
> Screwy



for $100, I might give it a go.
I need to know a lot more about the circuit and some basic info like what range the pressure sensor works.

although, I do like the idea of the conductance probes. It is what we have settled on at work.


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## djar007 (28/6/13)

Digging up an old post .But most of the participants are still here. I have a few questions on flow meters. This type . Would suit my system perfectly as I have a 240 v pump for recirc and a 12v little brown pump to fill and drain the vessel. My little brown pump is powered o and off by a simple switch. I was originally looking for a basic inline flow meter . I read a lot about the inaccuracy of such meters. I came across the linked setup and would be able to easily adapt it to my system behind the scenes and out of sight. The lcd would mount nicely above my brew controller. I would only need the flow meter for cold water into the vessel. Set my quantity and let it fill. Buzzer sounds and I flick the off switch on the little brown pump. I would only be looking at controlling up to about 65 litres of water into my unit. Volumes would be changing for each different batch type and size.

So my questions are these:
Is anyone out there using something like this successfully? If so what and how is the usefulness/accuracy ?
Is there something a little more simple that will just give me a digital count ? Any home brew supplies offer anything like this?
Has anyone got any working examples of a hall monitor sensor being used with an Arduino? I have only seen links to parts.

I know that the thread is old. I came to it whilst researching my way through a few threads and thought this was the best spot for my post. I am hoping that the technology has improved the accuracy of these sensors over time. I am not really interested in other types of indicators or switches as this particular setup suits my purpose and setup.Regards Dave


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