water level inspection system

[kelvin tay]

I would like to implement a water level inspection system, but i want to produce a hardware too...

Anybodys who got this kind of experiences, please share with me...

I will appreciate all of your guidances. Looks forward your reply eagerly.

Thank you very much.

[Henrik_Volkers]

Range?

Resolution?

Price?

Drift?

Aging?

Monitoring a water tank level under pressure ?

EX class?

?????

There are many many  of systems with various principles on the market, each for their specific use.

At home for rain water tank you can build a DIY capacitive sensor with twisted pair cable and a 555 timer

on the other end are EX class sensors for industrial use... 

What do you need?

[kelvin tay]

I just want to produce a simple prototype for measure the water height with range (0-20 cm), only water, not other liquid...

Can u please suggest me which kind of sensor is better? because i hav never done this before....and also still learning LABview...so I dun know which is suitable... 

[Henrik_Volkers · Accepted solution]

Very simple: Use the level control of a toilet reservoir and add a potentiometer, ok only use the potentiometer (it`s wise to use a more protected one 😉 and replace the knob with a peace of aluminum with an old tennisball at the end. Use the potentiometer (10kOhm) as a voltage divider (one leg(CW) to AGND, CCW at Vcc(5V) and the tap to Analog in) 

If the water level is regularly down, take a look at the way modern laundry appliances use: they use a pressure sensor with an air filled tube.

Very nice is a absolute pressure sensor suitable to be dropped into the water. 

However: Water and electricity don't mix well, so take care what you do. If humans can touch the water, all devices have to meet strict isolation classes. Normally the inputs of a PC card don't meet them!