Automatic Control Valves

[_shorty_]

Hey guys, New to the threads. Been searching forum for a couple days now, off and on, and can't seem to find my answer.
Many people use the term 'control valve', but no-one (that I've seen) really tells what types of valves or where they get them.

I'm in planning stage for my system, and am hoping to automate as much as possible. I found good affordable PLCs (controlers) at automationdirect.com, and am coming along with other needed hardware. I'm hoping someone could point me to some affordable control valves. I'm looking for analog flow control valves. What I've found so far are crazy expensive, so if someone has an affordable or DIY version of one, I'd greatly appreciate some info on it.

Also, if anyone can make recommendations on flow meters? That'd be great too! Whether electronic or analog readout...

 

[DaveMorris]

The only electronic or solenoid control valves that I have found that are even remotely cost effective are for 1/4" lines. Anything bigger than that gets expensive extremely fast. None of the sprinkler type valves will work because they all rely on back pressure. I did a lot of research on it and pretty much came up empty. You need food grade valves so that you don't have any exposed metals that would corrode with saltwater. I got two 1/2" valves that a friend stumbled across at a surplus shop for $10 each. That was just pure luck. Maybe somebody else on here has had more luck than I did.

 

[AquaticFins]

Are you looking for electronically actuated or hydraulically actuated valves?

 

[_shorty_]

Really, anything that's cost effective. Electrically, would probably be easiest. Hydraulically actuated vlvs would require more hardware... So, again, whatever is cost effective and available.

Also any suggestions of electronic solenoid valves would also be helpful

Also flow meters suggestions.

In doing more research... I started looking into using rotameters to measure and manually adjust flow... but that's not as fun...

 

[Perched Urchin]

Dave Morris,
How do the sprinkler valves rely on back pressure? I had picked up a few of these and didn't see anything on the box mentioning they won't work if not under pressure. I thought they were just typical solenoids.

 

[tkeracer619]

What are you trying to automate with all these control valves?

 

[DaveMorris]

Dave Morris,
How do the sprinkler valves rely on back pressure? I had picked up a few of these and didn't see anything on the box mentioning they won't work if not under pressure. I thought they were just typical solenoids.

From what I can tell, the solenoid only removes the pressure holding back the valve diaphragm. Water pressure is needed to push the diaphragm open and allow flow. The solenoids work fine, but I could never get the valve to work for a very low pressure scenario I was trying to set up. The back pressure issue is what I was told by folks here when I started asking the questions. If you find some that work, by all means share the info with us. I still have several things that I would like to automate using auto valves.

 

[tkeracer619]

Ill ask again?

Why the control valves?

You really need to consult someone on your ideas not just how to get parts for your ideas. The only thing I can think of where you would need automated valves is for a water change system. You are barking up the wrong tree if so and potentially setting yourself up for a costly disaster.

 

[DaveMorris]

Ill ask again?

Why the control valves?

You really need to consult someone on your ideas not just how to get parts for your ideas. The only thing I can think of where you would need automated valves is for a water change system. You are barking up the wrong tree if so and potentially setting yourself up for a costly disaster.

I respectfully disagree. I will be setting up a system that will do water changes automatically and with the technology available today it is very easy to build in failsafes that will prevent disaster. I travel for work, sometimes for two or more weeks and I would rather not go that long without doing some of my routine maintenance. Things like rinsing my MRC skimmer cup, water changes, spraying my mangroves, etc. Automated valves are a great way to do these things. The trick is finding a way to do it without breaking the bank.

 

[tkeracer619]

Why not do whats already proven reliable and use a reef filler pump on a timer for water changes if thats what its for.

Use a pump in a reservoir or a solenoid controlled by your RKE to spray the mangroves.

I have used the sprinkler stuff to wash down large skimmers and it really didn't do a good job. If it did bubble king wouldn't have wash down systems that cost $2000+.

I wouldn't want much of anything automated if I was leaving for that long. Too many things to go wrong and fail safes usually just turn things off. That wont help if a valve gets stuck open and drains your tank with nobody around. We can easily agree to disagree but I still think using flow meters and control valves to do a water change is making something easy complex and failure prone.

 

[DaveMorris]

I guess I just think the opposite of how you do. I think my travel requires me to automate more. The automation also leads to better stability because things happen more consistently. Yes it does add a level of complication to it, but if I am willing to do that, I don't see the problem. When trouble does arise, I can reset things and reprogram things to make corrections. This of course is still knowing that my wife can address an issue if it is a significant problem that needs a more hands on approach.

 

[dan223]

Most CV's are built for industrial and hvac and cost will be up there. As said already wc's can be done with pumps already out there that are set up specifically for it, they take out and replace equal amounts, like the litre meter system. The collection cup for skimmer can be tapped and run to a larger collection container, automatically rinsing the collection cup would only clean the outer part and not the inside neck which is probably more important. Theres no need to over complicate things unless money and time are no object and it would be fun for you.

 

[_shorty_]

Part of my job is controls programming... so, 1) I thought it'd be fun. But also, 2) I was looking to create a system that I could add to later. The plan was to fully automate it. I could control (via shared sump and large pump) to multiple tanks including the quarantine tank. Then at the push of a button I could switch to 'quarantine' mode to isolate the quarantine tank. I have lots of ideas... but it looks like finding cost effective hardware is my limitation. I could re-evaluate things by looking at individually sized pumps like you're talking about... But, that's still not quite as fun.

I'd thought of using a stepper motor to create my own to mimic an analog control valve.. but not sure if I have the time right now to tackle that...