Controlling HLT water fill automatically

[Windsors]

I have water fill with valve right next to my HLT. I am going to install a solenoid valve to turn the water on and off. I want to control it with 2 momentary push-buttons and do the following:

1. Start button - Opens the valve and fills until I hit the float switch level and valve close or until I hit the stop switch

2. Stop button - closes the valve when pushed.

Would 2 normally open momentary switches, one latching relay, normally closed float switch and one normally closed solenoid valve do this for me ?

Thanks

 

[Cpt_Kirks]

I have been thinking on this for my electric HLT.

I know it sounds bad, but I wonder if a toilet float valve would work for this?

 

[GilaMinumBeer]

I have been thinking on this for my electric HLT.

I know it sounds bad, but I wonder if a toilet float valve would work for this?

How clean is your toilet?


I have been considering a float switch too. Integrated into my BM.

 

[Bobby_M]

A thru wall float valve would be much easier.

 

[Munsoned]

I was thinking of a solenoid hooked up to one of those B3 float switches. Haven't really started to design my rig yet though, so no idea how feasible/expensive that would be...

 

[Windsors]

The float switch definitely works for the original fill volume and to keep it from overflowing. I will use one installed from the lid that i can adjust in height so I can set my fill vlume in the beginning and let it fly.

I do want to be able to add on the fly for what ever reason including cleaning at the end.

That's why I want push button control in addition to the upper limit control provided by the float switch.

 

[wehumble]

I think you are going to want a normally open start button and a normally closed stop. Pushing the start button closes the circuit and latches the relay. Push the normally closed stop button and the circuit breaks. Trip the normally closed float switch and the circuit breaks.

I've been toying with a design for my 'ultimate' brew rig and I want an auto-fill just like you're talking about.

 

[airbalancer]

My system uses one switch, one relay, and a float valve mounted in the lid. So when it turn it on it will fill until either the switch is turned off or the float valve is reached. You can add water at any time as long as the float switch is not reached. You just need a panel light so you remember to turn it off after it fills.

 

[weirdboy]

I think when I do this in a true automated fashion, I will use something like a potentiometer or similar so that I can set a desired volume without having to screw around manually with float valves.

Like, I could just program in the recipe and have it use the correct mash and sparge volumes.

 

[kladue]

The automation sounds easy but the programming is the biggest hurdle, the more you want to do the longer it takes to program. I have invested a significant amount of time to reach that goal with an automated system.

 

[diatonic]

I would love to be able to use a pressure sensor at the bottom of the vessel to sense level. It would have to be very sensitive (~1 psig) to maintain accuracy across 20" of water. I spent about 4 years on a submarine where I could glance at seawater pressure to tell how deep we were... Rule of thumb was 100 ft deep for every 44 psi.

 

[CodeRage]

I have water fill with valve right next to my HLT. I am going to install a solenoid valve to turn the water on and off. I want to control it with 2 momentary push-buttons and do the following:

1. Start button - Opens the valve and fills until I hit the float switch level and valve close or until I hit the stop switch

2. Stop button - closes the valve when pushed.

Would 2 normally open momentary switches, one latching relay, normally closed float switch and one normally closed solenoid valve do this for me ?

Thanks

In the primer in my sig there is a reference to an E-stop /stop/start circuit. Use that but add a NC float valve in series with the what would be the stop/e-stop button. Then use the auxillary contact on the control relay to drive the normally closed solenoid.

Pressing the start button causes the relay to latch close and if the float hits or the stop button is hit it will cause the latch circuit to fall out, thus closing the solenoid.


As for level measurement 2.31 ft per psi. Freescale makes some pretty nice 1.45 psig pressure transducers. Good for reading up to 3.35 ft of head pressure. run the 0-5V output into a 12 to 16 bit a2d and your in bitness... I've had a fair bit of success using one with a bubbler.

calculating volume is just a matter of applying pi*r^2 *psi*2.31/19.25 =gal

to use this kind of setup with out a controller you could use a pot as a voltage divider and the output of the freescale into an op amp set up as a comparator. The op amp's output goes true when the voltage from the PIT is greater than the voltage reference generated by the pot.

 

[Funkenjaeger]

I would love to be able to use a pressure sensor at the bottom of the vessel to sense level. It would have to be very sensitive (~1 psig) to maintain accuracy across 20" of water. I spent about 4 years on a submarine where I could glance at seawater pressure to tell how deep we were... Rule of thumb was 100 ft deep for every 44 psi.

People do just that - for example, a number of the people on the BrewTroller forum, including myself and CodeRage.

I don't think anyone's really characterized actual accuracy, but I do know that you can achieve precision on the order of 1mm water depth.

The challenge is in reliably feeding the sensor with the pressure. There's a lot of discussion in the BrewTroller group about solutions, and a couple that seem to work well, but it's definitely more of a challenge than you might think at first glance.

 

[Windsors]

thanks for all of the replies.

CodeRage, I went back and re-read your e- primer. Excellent.

Question - Is there a parts list somewhere for the components and good sources needed to make the E-stop circuit for a 50 Amp , 240 V panel ? I do recall seeing something in a thread you were helping out on, but I can't find it now.

Thanks

 

[CodeRage]

thanks for all of the replies.

CodeRage, I went back and re-read your e- primer. Excellent.

Question - Is there a parts list somewhere for the components and good sources needed to make the E-stop circuit for a 50 Amp , 240 V panel ? I do recall seeing something in a thread you were helping out on, but I can't find it now.

Thanks

No problem.

Here is the contactor
It says 40A but it has a 50A resistive load rating which is what we need.

E-Stop

regular stop button

and a start button

relay & base

 

[Windsors]

Thanks CodeRage

 

[kladue]

Here is something no one has seemed to have thought about, an adjustable water level switch for a washing machine, 110 rated contacts, variable trip point/level settings, and a $30 or less price tag. This would connect to bottom of keg or could use a tube on the inside like the wash machines do, and would not need additional relays to work. A center off SPDT switch along with level switch would make it possible to manually or automaticaly control a solenoid for water fill.

 

[egurney]

Pressing the start button causes the relay to latch close and if the float hits or the stop button is hit it will cause the latch circuit to fall out, thus closing the solenoid.

Would it be possible to keep the circuit live until turned off. That way it could keep the water level constant. Thinking of putting something like on my HLT to keep the element from burning out after having a few during a brew session.

Eric

 

[GilaMinumBeer]

Here is something no one has seemed to have thought about, an adjustable water level switch for a washing machine, 110 rated contacts, variable trip point/level settings, and a $30 or less price tag. This would connect to bottom of keg or could use a tube on the inside like the wash machines do, and would not need additional relays to work. A center off SPDT switch along with level switch would make it possible to manually or automaticaly control a solenoid for water fill.

Funny, I was looking at this as a sparge pump control. Most of the float switches I see are low voltage.

Looking around i came across www.washerwatcher.com , I am thinking I might get this and dissect it to wire between my pump and the output of my PLC. All I need is a normally open SPST switch with 110v+ rating. The sensor is solid state too.

 

[rabeb25]

On My old old setup I put a HLT float on from my RO system.