Help needed: Arduino and ultra sonic sensor for measuring water level

I have a 5.000 liter water tank in my garden that I would like to measure using a ultrasonic sensor and my Raspberry PI. The termporary hardware setup was easy and also the software implementation was totally fine. So the tests that I made were all succesfull.

In my test setup the wiring was only temporary and in the final installation I need to lay the cable in the ready existing cable channel that is in the ground.
My problem ist that I was not able to get the pull wire completely into the cable channel - maybe there is a tight rounding in the cable channel that dissallows me to get through.
By this fact I was pretty annoyed the last weekend - but I need to find alternatives.

The Idea:
Control the Ultrasonic Sensor locally with an Arduino (which is much more lightweigth than the raspberry) - both placed in the water tank, run the Arduino with a battery and transmit the data via wireless lan or via a 433MHz link to the raspberry.

What do you think about it? Any suggestions.

Thanks a lot

André

I would only place the sensor in the water tanks and all the other electronics outside as water is corrosive.
Be aware that in a water tank the relative humidity is high, which affects the speed of sound of the sensor.

So make some reference measurements with the sensor (use a stick to get the factual value) to create a lookup table.

Then interpolate in the table to get a quite reasonable measurement.

If you check the sensors subsection you will find more water level measurements tools and sketches (upper right is a search box)

To keep the Arduino close by why not use a project box? The sensor could be mounted on the outside of the box while the Arduino could be protected inside of it.

other related thread - Measuring water-level in a plastic storage box - Sensors - Arduino Forum -

One more;-

sonnyyu:
We have an other thread talk about water level measurement;-

The method is discussed at thread:

Ultrasound
Pressure sensor
X band Proximity Sensor
Ku band Proximity Sensor
K band Proximity Sensor
Sound
315MHz/433MHz rf-link Arduino (radio waves blocked by water)
Bluetooth Proximity Sensor
VLF radio waves (3–30 kHz) (radio waves through by water)
Laser-based water level sensor
Capacitance proximity sensor
Resistance proximity sensor
Measurement the pump discharge pressure (if there is pump)
Float switch

http://arduino.cc/forum/index.php/topic,160378.0.html

Thanks for your replies!
The intention of my question is more to get an idea if it is possible

  • to run the arduino (in a completely waterproof box) with batteries
  • transmit via wirelesslan when the sensor is in a water tank that is outside burried in the ground and covered by a lid of steel a. How about the range? Is Wireless lan okay? Or would you prefer another link?

Thanks !

André

to run the arduino (in a completely waterproof box) with batteries

Yes, Underwater Enclosure IP68.

transmit via wirelesslan when the sensor is in a water tank that is outside burried in the ground and covered by a lid of steel a. How about the range? Is Wireless lan okay? Or would you prefer another link?

pressure sensor, wired,

http://forum.arduino.cc/index.php?topic=160378.msg1200683#msg1200683