Positioning valve actuator for liquid

I'm looking for a ball valve with a positioning actuator. The purpose is to control liquid pump volume output with a feedback loop, through an Arduino, from a flow meter.

So far, cheapest is a valve with a pneumatic actuator for over four hundred.

Any thoughts?

Depending on the setup, you could use pressure sensors to determine how much liquid has left or entered a vessel. I realize it is not was you were asking, however another way to skin a cat or brew a beer I will be using them with my brewtroller in order to determine a vessel's volume and turn off valves when at desired volume.

What will they be used for, just trying to find a budget way.

Sorry to be vague, the valve would be used to control the flow rate (gpm, cfs) out of pump. (My preference is to use a stepper motor on a pump, but that's expensive for the rates I would like to see.) I can think of a few possible applications:

1. When using a reverse chiller, to slow pump rate down through chiller to improve heat exchange, until outflow temperature of wort reaches desired point.

2. When recirculating, sparging, and draining mash tun, to prevent negative pressure under grain. And prevent a stuck mash.

3. To control how fast wort moves between tuns and fermenters.

4. To eliminate the need to stir the tun with a mechanical vane, just let the pumped water do it.

There may be some problems because the valve can create a Venturi effect on the fluid.

Look at Belimo valves for electric actuated ball valves, around $200 new, much less from Ebay, only problem is Arduino will not output the 1-10V signal needed to control position.

Thanks kladue, if I remember my electricity and electronics correctly, the analog 4-20mA signal out of Arduino must have a voltage side to it, possibly (from memory) 0-5V. It still might work, I'll check it out. Thanks.

I found this about converting 0-5V to 0-10V. Good starting point. http://www.nano-reef.com/forums/index.php?showtopic=230743

So with kladue's advice, I bought a Belimo actuator and valve. Decided to buy these features:

1. CCV ball valve because it has a linear profile;

2. Three-way action to give more flexibility; and

3. Floating-point actuator because it is cheaper.

Found it on eBay for 40 bucks, free shipping!

It arrives next week. It will be the first piece of automated equipment since I bought my Arduino.

:-D

Now you can use 2 digital points and control it without much code difficulty, pulse up / down in response to flow. A suggestion is to write a "Home" sequence to preposition the valve for startup, all the way in one direction then back the other way 45 seconds to be centered as the actuator is a 90 second travel stop to stop.

It's a little different approach but I have used a light dimmer switch to modulate my pump speeds for transfering (racking). Maybe a combination of valve position and pump speed?

I got the Belimo today. I'm worried the orifice in the valve is too small. Its a 1/2" valve, the orifice is 3/8" x 1/8". I'm worried it will introduce air into the wort or water.

Is the "orifice" a colored piece of plastic with a slot?, if so then there should be a snap ring holding it in place. Pop the snap ring and push the plastic orifice out and you should have a nearly full opening ball behind that.

Thanks, Yes. I saw that. I don't need the more exacting flow control from that insert? I planned to call Belimo tomorrow to ask about a bigger one. Not necessary ?

You can save the plastic for now, but having used these valves in a brew system you will find that you do not need the restriction when working with the low head pressure circulating pumps.

Thanks

Kladue, how can I get 24VAC pulse control of my Belimo TR24-3 (floating point) without software? I'm looking for cost effective and simple a hardware approach. Thanks in advance!

I have a HERMS and wants to use the Belimo valve as the bypass for my HE so I can automatically control the position of my bypass valve. I continually heat my HLT during the mash so that at the end of the mash I am at sparge temp. So my HE bypass valve (Belimo) needs to be slowly throttled open as the HLT temp rises to maintain a constant HE outlet temp back to Mash Tun.

Or should I order the TR24-SR (proportional) and hook it up to an Auber PID?

It will cost a bit more but a PID controller with 0-10V output will simplify the control considerably when using the Belimo SR proportional control actuator. A suitable model from Automation direct would be the SL4824-LR which has a 0-10V output, and has companion software available for setup. You will need 24V to power the valve in addition to the control signal, but the valve works equally well with either 24V DC or AC power so a simple 24V transformer will do the job. Be aware the valve will start to move at 2V input and complete travel at 10V, so do not expect it to move below 20% controller output.
If you are patient and willing to cruise Ebay for process controllers with voltage outputs or 4-20 milliamp outputs you might be able to save some cash.

SMc0724 said:

I'm looking for a ball valve with a positioning actuator. The purpose is to control liquid pump volume output with a feedback loop, through an Arduino, from a flow meter.

Click to expand...

What flowmeter are you using?

Thanks for the help Kladue! I ordered the SL4824-LR (with PC USB adapter), an RTD, and the Belimo SR tonight. Maybe this is a silly question but where do I get a 'simple' 24V transformer? Also, I don't mind the actuator/valve not responding below 20% of the controller output. Could I have avoided this by using the SL4824-CR version with 4-20mA output (the actuator takes either 0-10VDC or 4-20mA)? Just curious.

BTW, you have quite the setup! I'm a nuclear engineer and most of my work is refueling reactors. We have reactor vessel purge systems that are pretty complex but your brew system blows them out of the water! Impressive!

nvrstck said:

...
Maybe this is a silly question but where do I get a 'simple' 24V transformer?
...

Click to expand...

Some doorbell transformers can supply 24VAC. They are easy to find and inexpensive.

The valves do not draw much power ( about 4 watts) so a 20VA rated 24 volt transformer from Home Depot will work.
I work in the industrial instrumentation field so the brewing system control system design build is like what I have been doing for quite a while.

I've not decided on the flow meter yet.

Late to the conversation, but is there any reason any electric ball valve with manual override couldn't be used?

The manual override should just be a "Knob" on the top that rotates with actuation right?
Thinking something like this: http://www.oscsys.com/store/product/291

Then figure out a way to couple a rotary encoder to the manual knob to sense the real world position of the valve? http://www.oscsys.com/store/product/1001689

Parsing the output from the encoder should be a lot easier than all the crap you need to do to make a 0-10v transition with the controller.

But then again, I'm just guessing