Is there scope for the float to ride up and down within a "stilling tube"? The idea is that the tube protects the float from any waves and splashing within the tank that might cause the readings to fluctuate unneccessarily.

These type of thing are available of the shelve try:-

www.ott-hydrometry.de/web/ott_de.nsf/id/pa_c31_e.html

Designing and making as a DIY project would also be easy.

A boom with a float at the end with a sensor at the pivot, an AtoD converter and a PC just do fine after some calibration.

A float on a slide will also work.

Note on both options the reading will change (like in a car petrol gauge) if the tank is traveling up or down hill. ( I could not resist)

what kind of water are you measuring?

Go to www.ayvaz.com and see the level float switches/indicators to get the idea.

My Dear,

It is only monitoring the level locally your need? If you want to monitor and control the level then i don't recommend the float type instruments that they have many disadvantages.

Hello, my idea would be enough equal weights on both ends of a cable to overcome the cable and pulley resistance. Think elevator. Then a good size float on the inside weight and some type of pointer on the outside weight.

As the water level drops the weight and float being a little heaver than the out side weight and pointer follows the water level. Then as the water level rises the water pushes on the float which makes the inside weight lighter than the outside weight and pointer then goes down.

The weights I would think would need to be several hundred pownds each. So a small change in ballance would cause movement one way or another.

The scale on the outside would read full with the pointer down lowe and empty when the pointer is near the top. If you built a frame on top edge of the tank high enough you could read to the very top if you needed to.

Now if you wanted electrical measurment and or control a differntal transmitter with the high side attached to a port at the bottom then the low side open to atmosphere or top of tank if closed. Then to calabrate measure empty then full. You then calulate the volume in the tank by the reading. The meters can have a local display with remote dispalays also.

Hope this helps

metalSmith's

thanks so much guys.. actually i'll be using it just to determine the level of a 1 million gallon water tank .. the elevator idea is my initial approach.. my problem is where i can get the float i'll be using.. if it will be fabricated what material would i use? dimensions??? thnx a lot guys..

A manufacturer for floats.

http://www.ensim.com.tr/ensim-lonca/index.html

Hello, if you want to do it on the cheap find a 30 gal drum poly/metal, fill it with foam Like the expanded polystyrene (EPS) , or a two part expandable urethane foam

computer glitzed.

Take a cable, chain,threaded rod, your choice. Through the center of drum to attached the weight on one end and the cable to the other end. That goes up and over the side to the other counter weight.

By using the foam, the drum will never fail and it's heavy enough to tip the weights to the tank side but the buoy's is enough to offset it's own weight. So it will follow the water level.

The EPS blocks is cheaper than the urethane I think, the link on urethane gives more info on it's properties.

hope this helps you.

metalSmith's