how to keep R/O from starting/stopping to fill top off container

sdf_beanhead · #1 07/09/2007, 09:28 PM

I have not found any good info on setting up a Top off system that allows you to fill your top off water container when it is empty and stop the R/O unit when it is full, so your R/O unit doesn't start and stop constantly.

I cannot wrap my head around how to setup the float switches and relays. I think I need to use latching relays, but I still don't really know how to wire it.

Any help would be appreciated.

volpe315 · #2 07/09/2007, 09:49 PM

http://www.melevsreef.com/plumbing/auto_topoff.html

check out this site this guy has ton of info

melev · #3 07/10/2007, 02:54 AM

Hey Blake. I use a float valve in my 55 gallon drum. When the float rises up, it creates back pressure in the RO system to the point that the ASOV turns off the system and water ceases to run out the waste line.

Paul,

[welcome]

So you're the guy using up all my bandwidth?

JCTewks · #4 07/10/2007, 03:12 AM

After the float and auto shut off kick the water flow off, you'll need to shut off the inflow of water to the system before you remove any water from the resorvoir to keep it from cycling and causing high TDS. I'm not sure if there is a way to get around the whole having to shut off the feed without using a controller and some solenoids.

manderx · #5 07/10/2007, 03:14 AM

put a solenoid in front of the RO and hook it to a timer so that it's only on just long enough to fill your reservoir (via float valve and asov). this way it only comes on once a day. or you can go with a really small reservoir and have it come on twice a day or whatever.

this keeps the ro from cycling, and it gives you some protection against a float valve failure.

GuySmilie · #6 07/10/2007, 09:04 AM

=edited=

I mis-understood your question.
Sorry, disregard.

silverwolf72 · #7 07/10/2007, 12:06 PM

I posted a thread for a cheap delay timer that would work perfectly for this, can be set to engage a relay from 1 to 60sec triggered by a float switch.

sdf_beanhead · #8 07/10/2007, 01:37 PM

Thanks for all your suggestions. I would like to do something like weatherson has setup. But instead of coming out of the RO unit, the water would come from my shared top off container in th garage. Also, I would like to do this with float switches. If you look at http://www.autotopoff.com/custom.html there is what they call a "latching" upgrade. what they describe thereis what I would like to do. Thanks for your help.

FuzzyLogic · #9 07/10/2007, 01:47 PM

Latched relay w/2 float switches

melev · #10 07/10/2007, 03:22 PM

Now that is what I call a useful layout! I love that it is animated as I always have trouble understanding electrical diagrams.

sdf_beanhead · #11 07/10/2007, 05:30 PM

WOW!! That is not a latching relay is it? That is a latching circuit, right?

What is the purpose of the diode?

FuzzyLogic · #12 07/10/2007, 05:48 PM

RC member beanimal explained the diode best:

Quote:

Originally posted by BeanAnimal
The diode is to help abosrb the back emf (inductive kick) that occurs when the relay field colapses. This will help protect the delicate reed switch in the float assembly.

Explanation:
When the power is removed from the relay, the armature is quickly shoved back through the bobbin (the coil) by the return spring. This action produces electricity. In addition the relay bobbin and armature are saturated with electrons that are released when the electromagnetic field colapses.

Any small 1n4xxx series should work.

For those interesed:
There are many relay coil suppression methods... this is one will work well for our purposes. You should not that ANY suppression slows down (dampens) the field collapse and therefore slows down the movement of the relay. This in turn can cause arcing at the relay contacts. This should not be a problem in our application... but HIGH VOLTAGE HIGH CURRENT applications can be affected. In those cases stronger relay springs, contact configurations and other suppression means should be explored.

Bean

sdf_beanhead · #13 07/10/2007, 06:19 PM

It is so simple, and I can't figure out why I did not put that together. I think I was just in a hurry trying to come up with the circuit and got frustrated which didn't help in laying out the circuit.

I thank you VERY much. We need to add this to someone's site or something.

Again thank you, I will probably use one of the other solutions for my main top off water container in the garage (it feeds top off containers for my two tanks)

melev · #14 07/10/2007, 06:32 PM

Was that a hint? I mean, if it is I'll have to actually make this thing first.

MeuserReef · #15 07/10/2007, 06:51 PM

Quote:

Originally posted by melev
Was that a hint? I mean, if it is I'll have to actually make this thing first.

[color=light blue][readers chanting][/color]

BUILD IT!
BUILD IT!
BUILD IT!

ps...

Marc, is your term in the oval office over?

melev · #16 07/10/2007, 07:07 PM

My term ended July 1st. I'm now a normal guy without a title.

MeuserReef · #17 07/10/2007, 07:22 PM

Quote:

Originally posted by melev
I'm now a normal guy without a title.

Thats before you go in the phone booth, right Clark?

LOL. Glad to see that you all are getting a break from the rain up there.

sdf_beanhead · #18 07/10/2007, 08:04 PM

It could be a hint. I already built it and it works like a charm. I need to get my website hosted somewhere because right now I am serving it off of my internet connection now.

Speaking of rain. I thought I was living in the tropics the way it has been raining everyday. This is weird for July.

MeuserReef · #19 07/10/2007, 09:12 PM

Quote:

Originally posted by sdf_beanhead
It could be a hint. I already built it and it works like a charm.

Where did you get your latching relay?

I like the idea of the less frequent cycling... Heres how I accomplish the short-cycling issue:

I currently have my RO unit hooked up so that it refills my sump directly. There are 2 float switches that are wired together into a DPDT relay. The relay sends power to two solenoids hooked in series (in case on fails). The entire ATO system is powered via a timer that only powers the ATO on for 15 min a day. This way, even if all of my float switches stick and both solenoids fail... I can still only produce 15 minutes worth of water... which is about how much the tank evaporates in a day.

The only time that the RO unit will cycle on and off rapidly is if Im messing in the sump and cause the water level to move up and down during the 15 minute "on time"

sdf_beanhead · #20 07/11/2007, 08:56 AM

It is NOT a latching relay. IT is just a regular 12v DPDT relay. The latching is caused by the way the 12v power is routed through one side of the relay and the float switches.

If you wire it up like the image shows you it will work. I don't have my float switches yet, but I do have several wall light switches. I hooked it up with those in place of the float switches and TaDa it works. I will put the guts in a project box and take a pic as soon as I get a chance.

King-Kong · #21 07/11/2007, 10:18 AM

Man.. I suck at electrical... is there any additional reading material you could point me to so that I can make sense of how that is working?

sdf_beanhead · #22 07/11/2007, 01:24 PM

a quick google search for basic electrical symbols will give you the meaning of the symbols, but for the concepts, you might want to pick up a basic/beginner electronics book. I hate to say it, but my favorite local electronic "do-dad" shop was Radio Shack until they became Cellphone/Satellite TV Shack (in my mind). They had several VERY basic electronic circuit books that went over the basics and gave examples, and it gave you the part numbers to buy from radio shack. But sadly Radio Shack is trying to change it's "image" to be more like Best Buy and Circuit City which means the parts section is getting smaller and smaller.

Anyway, what part are you not understanding? The picture of the circuit is just a logical layout of the circuit. It may not look like that when you wire it. I will try to take a picture of my temporary wiring job and post it for comparison.

Does anyone know of a REALLY cheap place to get float valves? I need 8 total to get both of my tanks topping off automatically (with safety backups of course). Aquahub charges $6.99 for theirs and that comes out to $55.92.

melev · #23 07/12/2007, 02:34 AM

You said float valves, but I'm guessing meant float switches since you referred to aquahub.com... I buy float valves from USPlastics.com for just slightly less than $6.99

Switches from AquaHub.com - man, I remember when they were only $3 each. Everything is going up in price.

sdf_beanhead · #24 07/12/2007, 10:36 AM

I meant Float switches

Thanks for the heads up on the float valve though because I need one of those also. Which one by the way? And I WAS going to order one from Marine Depot for $17.99

With my affinity technology and automation, I should have chosen a cheaper hobby, but it is too late now... I am waist deep and am not looking for a way out.

melev · #25 07/12/2007, 03:17 PM

I like this one because you can use it vertically or horizontally. It is adjustable. When I got ready to order them, we had a group buy and I ordered 20. If I recall correctly, the total shipped come out to $6.25 per person because the price goes down as you order more at a time.