[Sven337] just blogged about a gas consumption monitoring setup he finished not long ago. As his gas meter was located outside his apartment and nowhere near any electrical outlet, a battery-powered platform that could wirelessly send the current consumption data to his Raspberry Pi was required. His final solution therefore consists of a JeeNode coupled with the well known nRF24L01+ wireless transmitter, powered by 3 supposedly dead alkaline batteries.
[Sven337] carefully looked at the different techniques available to read the data from his meter. At first he had thought of using a reflective sensor to detect the number 6 which (in France at least) is designed to reflect light very well. He then finally settled for a magnetic based solution, as the Actaris G4 gas meter has a small depression intended for magnetic sensors. The PCB you see in the picture above therefore has a reed sensor and a debug LED. The four wires go to a plastic enclosure containing the JeeNode, a couple of LEDs and a reset switch. Using another nRF24L01, the Raspberry Pi finally receives the pulse count and reports it to an eeePC which takes care of the storage and graphing.
Great. And now make a deal with your local utillitites company that you send them your data daily or better more frequently so they can make a better prognosis while you save some money.
“His final solution” – don’t say that. It’s too soon.
The problem with smart gas meters is that they need to run on GAS. They aren’t to hip to run electric to the meter. Maybe an RFID with some of the lowest power chips out now.
I notice sealed parts, but I see an exposed pin and socket troublemaker in the foreground.
It is just a matter of replacing the REED with an optocoupler and you can read the electricity (and the water) meter(s) too. Interrupt driven, low power.
And at the jeelabs site you will find that these ‘nodes’ can run for eons on a single (‘dead’) battery.
Concern trolls seem to be quite active recently.
Odd because my smart gas meter runs on electricity. It has asolar panel in the top and a storage battery inside, I am betting the solar panel on top only extends the battery life, but honestly they only need to transmit a single low power burst daily.
not hard to do at all to make it run 10 years off of a set of lithium batteries inside it.
Mine (I looked it up) runs on lithium thionyl chloride batteries. Which I don’t think are rechargeable. Most British meters are in a cupboard, indoors to keep it out of the way, or outdoors to protect it from the elements.
In my case the electric meters are in a separate cupboard oppposite, but in many houses the electric and gas meters are next to each other. Seems a shame the utilities can’t have some arrangement where a gas meter can leach a little from the electric meter. I suppose it’d be more complex, failure-prone stuff to add to it, from the electric side. Though even a few mW would do. I wonder how practical it is to steal power by running a wire next to a mains-carrying cable.
Interesting design.
Wondering… is there some software to generate pinout diagrams like this:
http://perso.aquilenet.fr/~sven337/data/gas/qrc-jn-v6-part.png
?
Maybe my Node.js-Based RPi Smart Meter data collector is of interest: https://github.com/0xPIT/cubemeter
Note, the Pi has plenty of Horsepower and storage to do storage and graphing. pretty simply to take the data and serve it up via web page.
That’s exaclty what https://github.com/0xPIT/cubemeter does. I’ve added screenshots to the github page today.
I placed an IR on top and emitter on bottom of my gas meter connected to an arduino – using an analog pin and software filter (to try and filter out sunlight) to see the rise and fall of an rotating cam inside the meter – it has worked really well
I get 100 clicks per one ccf
Hm, good idea, taking advantage of an aspect of the mechanism that happens to serve your purpose. I wonder how much inside a gas meter is metallic? Perhaps placing a magnet nearby would give a magnetic field that varied in speed with gas usage, made up of eddies from some cog or cam.
looked like plastic to me – i played around with a reed switch and didn’t pick up anything – I noticed the cam moving and … and had a “I wonder if thought”
I got a hall effect sensor but never did anything with it – as what I had worked so well
here is my code and pic’s
http://forum.arduino.cc/index.php?topic=63375.msg1650153