Top-off Water Chg Schematics

[rharlow]

I am looking for comments on the attached schematic. My idea is to control the RO/DI to fill two reservoirs, a "water change" tank and a "Top-off" tank. The water change once filled will just sit until I add salt and the be manually valved into sump as water is removed. The Top-off will be controlled by a peristaltic pump feeding the Kalk reactor and going into sump for top-off. All these will be on timers to control when they are in operation, ie. Kalk during lights out.

I can put circuits together and read some schematics, but my electrical theory is way lacking! I've read here where it is advised to have a Diode and Zener across the coils. Would that be both coils on a dual coil relay? For diodes, would a 1N4001 or 04 be better. I've got a bunch as well as 1N5400 sitting around. Also, for this application, is a 1N4742A the right zener?

Please feel free to critique this schematic. Thanks for you insight and help!! Oh, by the way, I've never posted images, so this will be a first. If it doesn't work, or is too blurry, I'll try again. Thanks

Chip

 

[Liam]

very impressive schematic However i do not understand how it will work because you have top off and water change soleniods powered from the same timer/power source so in theory both your top off and waterchange will be powered at the same time.If i understand you correctly you will put the pumps on timers,so what if when the water change pump turns on via its timer and your water level is fine,as i interpret the diagram nothing will happen.
Also most evaporation occurs during lights on so relying on a seperate circuit to power a kalk reactor during lights out is the correct theory but you will probably find due to a low level off top off required at night that it will not provide much benefit for keeping ph up overnight you would be better off plumbing it into your regular top off and use it more for a means of precipitating phosphates and keeping ph generallly high.
In my experience automated water changes work well by using two pumps on the same timer,place one pump upsteam of the input from the new water input in the sump(this will prevent changing new water immediately) you need to use two ball valves to create an equal exchange rate(i timed mine many times into a marked bucket to make sure the rate was equal).This is far simpler.
Another piece of advice its to wire you float switches in series rather than parallel,this is a good failsafe in case one sticks.
I am sure it is an oversight but i think your LED's are back to front
Please LMK if i am interpreting it wrong,which is normally this case
-Liam.

 

[rharlow]

As far as schematics, I do have LEDs backwards, already fixed. I also made the "Solenoid On' LEDs in parrallel so as not to drop voltage to coil. As far as operation, this is what I envision. Also, this is for a 65gal tank w/ 15 gal sump.

I will have two water tanks, one for water change, maybe a 10gal, and one for top-off, maybe 2gal. The circuit on the left will automatically fill these tanks during the day. If either tank needs water, then RO/DI solenoid will be energized along with the respective tank solenoid. At night, I plan to drip Kalk using the right circuit energizing a perstaltic pump pulling water from the top-off tank and into Kalk reactor. For water changes, this will be gravity fed from the tank into the sump. I will have a tee off the "Main tank" to sump line that I can connect a hose to to fill up a waste tank. Essentially turning two valves on at the same time, one to bring clean water from water change into sump, the other to pull water out. Hope this makes sense.

As far as the floats, one is a low float and the other is a high float. I amy however put a mechanical float as a backup to the high float.

Hope this clarifies a little. Sorry the schematic turned out huge!!

Chip

 

[maurod]

Hey Chip!
I am about to order solenoids see this thread: http://www.bostonreefers.org/forums/showthread.php?t=14006

Let me know if I should order you a few.
I am also going to be ordering 10 float switches so as to have some supply for the club (and get free shipping)

M.

 

[rharlow]

Thanks Mauro for the thoughts. I t looks like the solenoids you're getting are not 120VAC. I'll be using 120VAC solenoids. I've sourced several spots, but still have yet to contact local plumbing for ice-maker solenoids. Thanks for thinking of me!!

Chip

 

[maurod]

Chip,
Most of these solenoids will fire at 120 - 12 VAC. It's a simple fix (and much safer!) to add in a voltage regulator to lower the voltage for the solenoid.

M.

 

[maurod]

I just checked the manufacturer's website for the solenoid - it will run on 110 voltage:
http://www.ksd.com.tw/en/htm/productgc_en.htm#o

 

[rharlow]

The one in the catalog is 24VAC. Yes the manufacturer does offer 120VAC as an option but it is a different model # solenoid. The coils are made to match whatever voltage you want, 24VAC, 120, 220 etc. His prices are good! I may adjust my system plan to go with 24VAC, but for now I'm planning on 110/120. Also, I've been looking for an all plastic solenoid (possibly delrin) to prevent any copper contamination. I see this have some sort of copper ring. Not sure if that is actually exposed to water. Again, thanks for the offer, but I'll pass at this time.

Chip