Touchless water level control... any interest?

[Reef55]

After reading all the nightmares over the years of top-off's failing, I decided to come up with a new way to monitor water level.

The problem in each case seems to have is whatever part touches the water is what fails. So my first requirement was that it can't touch the water. So, my design goals:

1) No sensor touches the water.
2) Very small so it could be used in nano tanks.
3) Adjustable distance that water level must change to trigger unit.
4) Redundant sensors.
5) Control either a water pump or solenoid, so it has to switch 120VAC.
6) Sense when the water is too low, and turn off the return pump.
7) Have visual (LED) indicators of the water level, if the topoff outlet was turned on, if the return pump is on or off.
8) If the water gets too high or too low, sound an alarm.


It has taken me quite some time, but I have the circuit design complete, with every goal accomplished.

Is this something anyone would be interested in? I will be building one for myself, but if there was more interest I would design circuitboards and have them made somewhere.

Thanks for any input,
Mark

 

[stugray]

You didnt explain how it works.

Does it use optical, acoustic, magic?

I designed an optical liquid level sensor that I thought was brilliant... until I figured out it was already on the market. It has no moving parts ( all solid state ), but it must still touch the water.

Stu

 

[eshook]

I am also curious how this works without touching the water?

I am planning on using an air-pressure system for my auto top-off. It has no moving parts and will not fail (in the on position) but it touches the water. The only missing component is that it won't shut off my return pump if the water gets too low, but I suppose I could get a different type of sensor for that if I wanted. Plus I would rather have a burnt pump ($50-$100) than a FW reef (don't even want to think about ;o)

Reef55 what is the magic behind your system, and better question how much will it cost?

 

[Reef55]

It uses light to sense the water level. Total cost of parts alone will be around $100.

 

[Palancar]

Would the sump have to be translucent?

 

[got2lb]

That's pretty much what the TUNZE OSMOLATOR does. It uses optical sensors to tell when the sump is low.

http://www.premiumaquatics.com/Merc...D&Product_Code=T3155.000&Category_Code=Dosers

 

[Donw]

I dont think there is a lack of interest. Light sensors or refractive sensors are what most call optical sensors. They are pretty cheap and easy to come by.

Don

http://reefcentral.com/gallery/data/500/58414dads_003.jpg

 

[Reef55]

The Tunze Osmolator uses a refractive optical sensor that comes in physical contact with the water to sense the water level. These cost around $20 each from what I have seen, and to sense 4 different levels of water would require 4 of them.

My design uses optical sensors that do not touch the water. The sensors are placed above the water and determine the depth of water away from them. Only one set of sensors needed.

 

[Donw]

<a href=showthread.php?s=&postid=6709664#post6709664 target=_blank>Originally posted</a> by Reef55
My design uses optical sensors that do not touch the water. The sensors are placed above the water and determine the depth of water away from them. Only one set of sensors needed.

Do you have any details. I'd like to hear more. How are you dealing with ambient light? Refraction due to turbulance? Turbidity?

Don

 

[gobygoby]

what if something in the water column goes through the path of the light? or a shadow? this doesnt seem to relaible to me....but what do I know?

Goby