Flukso water meter

The current application of Flukso lies in the monitoring of electricity consumption and photovoltaic production. From the very start though, there has always been the desire to monitor all household flows (hence the Flukso name). Monitoring electricity just seemed more straightforward and definitely less intrusive than monitoring resources like water or heating.

That is, until one of our 'Fluksonians' (thanks Michel!) pointed me to Lieven's water and gas meter hacking experiments at lika.be. Lieven uses a Hall-effect switch which can either be inserted in the water meter's drilling or glued to the gas meter. When such a Hall-effect sensor is located close enough to the meter's rotating magnet, a clean pulse can be derived from the sensor. This allows the sensor to be coupled to a modified Fluksometer, with an extra output for powering the sensor. This is why you find two cables connecting the Hall sensor to the Fluksometer in the picture below.

Water metering with a hall switchWater metering with a hall switch

This means we now have experimental support for water metering. Yay! Well, at least for a certain popular type of water meter in Belgium. I am interested in finding out whether this approach works with other types of water meters as well. Post a comment or contact me directly if you're interested in tinkering with your own water meter.

Again, kudos to Lieven for devising this elegant water and gas measurement hack! It allows us to re-purpose the utility meter to our own needs in a non-intrusive, non-seal-breaking and robust way. We might even not be voiding our warranty this time.


jmke's picture

very interesting results, but seems a lot more invasive than the clamps :)

icarus75's picture

Actually, it isn't. This type of water meter comes with a drilling already present. It's covered by a black plastic cover. We assume this is explicitly meant for automation purposes. We're just making use of it!

We think (unverified) that it's even possible to detect the magnet rotation by simply attaching the Hall switch to the outside of the water meter.


WCG_SYD_GHD's picture

Most water meters can be fitted with a "probe" which is nothing but a reed switch. These come in all sorts of shapes and sizes, ranging in price in Australia from A$30-150.

If you are after more than qualitative flow information, you need to find out how many litres of water need to flow through the meter to generate one pulse. For meters that look like a "hand grenade" (like in the picture above) count the number of red dials. If it's 4, more than likely it's 0.5L/pulse. If there are 3, then try 5L/pulse. Others come in 1, 10, or 100L/pulse.

This is what a smart water meter is all about.

If you want more info - or if I figure out how to upload a paper - I'd be quite happy to provide a detailed "How to smarten up a water meter" white paper.

We've been doing this professionally in OZ for over 5 years - and in fact this is exactly how I have been monitoring the rainwater supply in my house for over 3 weeks now. So I dare challenge about who has been first. ;-) lol

Keep up the great work.



icarus75: Here's a link to Guenther's white paper.

icarus75's picture

Hi Guenter,

This Fluksometer's firmware has been slightly modified to work with the water meter's 0.5L/pulse meter constant. So I'm pretty sure about having the first quantitatively 'correct' Flukso water meter. :-P

We intend to provide the meter constant as a user configurable setting in a future version.

You can attach a file in a forum topic, not within a comment. If you send me the white paper, I'd be happy to attach it to this blog post.


Wozzzaaa's picture

What a great idea.

Any aussies connected up their water meters yet?

Stijn Ruts's picture


Hoe heb je Hall effect switch aangesloten op de pulsingang?
Heb je hier dan 2 pulsingangen voor nodig?

hall effect switch heeft de volgende aansluitmogelijkeden:

VDD (supply) GND en Vout wat sluit jij daar dan op aan?



icarus75's picture

Hi Stijn,

I modified the internal Fluksometer wiring to have access to a 3.3V rail. I am currently experimenting with Reed switches for water measurements. These type of switches do not require any external powering. They can be hooked up to the standard pulse ports of the FLM.

ransbottyn's picture

What's the current status of monitoring the water and gas in Belgium with flukso? Still a hack? What components do I have to order to test this with my flukso ? I'm monitoring my 3 phase electricity and very happy with the flukso-results... looking forward to monitor my gas and water usage but it's not completely clear to me what to order?

icarus75's picture

We had to go through a couple of iterations to come up with a proper gas sensor. Both water and gas sensors are now in production. The sensors will be added to the web shop as soon as we've got them stocked. Thanks for the patience!

ransbottyn's picture

Thanks for the feedback, and just to know, is this a matter of weeks or months?

icarus75's picture

Should be a matter of weeks. :-)

icarus75's picture

Water and gas probes are now available through the Flukso shop.