GSM water level sensor

Other Hardware Sensors
1

Hi everyone,

I am in a search for a GSM water level sensor, based on the following specifications:

  • The water sensor level is to be used in the situation when the river water level is around 1,5m and 1,7m of the relevant point.
  • SMS message must be sent to dedicated decision-makers, which are concluding further instructions.
  • A simple Application (Web or Mobile) should be provided in order to manage responsible decision makers (add or remove users, and to check a vital sensor operation).

Furthermore:

  • Need to have a long battery life – more than a year
  • MUST BE low-cost / low-energy solution
  • Should contain: Microcontroller, GSM capability, up to 5 users), Water level sensor (e.g. SKU: SS-DS-02 | Vendor: TOMSON ELECTRONICS), waterproof (or separate sensitive parts from the water)

I haven't much experience with sensors, that's why I turned out to you guys. If someone can give me a tip where to find this sensor (if exists), or to whom shall I speak to (in case of building from the scratch).

The case is that we need approx. 2 sensors (which can make a situation a little bit more difficult), but I believe together we can bring a smart solution. :slight_smile:

THANK YOU for the help!

Gratefully,
Davor

Linda's sensor.pdf (598 KB)

2

Are you looking for someone to sell you a complete product, or do you want suggestions on how to build one yourself?

3

Hi,

Thanks for asking. I would like to build it up with some advices, but if someone wants to build it for us, it's also okay, since we pay for the services.

4

I'm in for such a job - but the big issue is the GSM part. Which module works, or is even legal, depends on your locality.

If your module is connected to the Internet (WiFi network available at place of installation), a push notification to an Android app may be easier to implement.

5

Yes, There is a Wi-Fi network close to the sensor, and I am looking to use it to send a message through Twilio account, do you have experience with that?

6

No experience with Twilio yet - I just browsed the site a bit and it looks pretty straightforward. They even provide sample code for the ESP8266, which would be my choice of processor for this application. Low power, inexpensive, built-in WiFi.

To come back to your requirements of above:

  • The water sensor level is to be used in the situation when the river water level is around 1,5m and 1,7m of the relevant point.

Most reliable will be two float sensors - not the conductive sensors as you drew in your original post. This for overall reliability of the sensors.
The mounting of these is paramount to them functioning properly as it's a river, so you have to protect them from dirt and debris that may block the sensor, or physically damage them (flotsam hitting a sensor). For that you may use a large diameter PVC pipe and mount them on the inside. The pipe goes in the water, and protects the sensors from most dirt and debris. Place the sensors 20 cm apart and the pipe at the correct overall level.
Even more robust would be a small capacitive sensor. There are sensors that are designed to detect water level from the outside of a bucket - those again could be built into a pipe, the pipe sealed (the sensors themselves should be water proof as well), and then the sensors basically check for water on the outside instead.

  • SMS message must be sent to dedicated decision-makers, which are concluding further instructions.

That can indeed be done via Twilio.

  • A simple Application (Web or Mobile) should be provided in order to manage responsible decision makers (add or remove users, and to check a vital sensor operation).

Twilio provides the account management application already.

The ESP may act as web server providing the current status, but it's probably better to do that through an external web server that the ESP checks in to, as otherwise you'd have to keep it connected all the time and that drains your batteries fast.

For power saving - you want it low power: have the device sleep, and every 30 minutes or so (up to you - can be more, can be less) wake up, check its sensors, send out SMS if needed, update its status on the external server, and go back to sleep. This is the best way to save power.

When checking the page on the external server available information would be: last time the ESP checked in; status of both level sensors; battery level.

7

Thank you for such a detailed explanation!

Cheers,
Davor

8

Just drop me a message if you want me to build this.
Capacitive sensor in PVC pipe should be the most robust, can quite easily be completely sealed.