Hi All
I'm new to this forum but are in the process of putting together my system.
I whish to log my Electrical power, Water, and heat consumption
I can see that there is a fine emontx V3 for the electrical power part and this logs and transfers the info the to the Raspberrry pi via RF
Now i have just had my house refurbished so my electrical power meter, my Water meter and my Heat meter are within 2 meters radius of each other so why not log all three directly via the Raspberry Pi, why use an additional power consuming device and transfer data via RF when i should be able to log it directly via the Raspberry Pi?
What am I missing?
Looking forward to hear from you
Br
Morten
Re: Why not using the Raspberry pi directly for logging values
The Raspberry Pi generally runs some kind of general purpose operating system and does not have the hardware required onboard to read analog sensors. To deal with live data, you really need to have a real time operating system to process the incoming data and output it in a usable form.
The amount of power an arduino uses is miniscule - somewhere on the order of 50mA which is just 0.25w, so hardly an amount to worry about.
RF isn't your only option, and neither is a Raspberry Pi. I am currently running my arduino via USB to an openwrt router, which sends data back via a python script.
My next phase will be to move the shield over to an Arduino Yun setup (which also uses openwrt) to have a more self contained unit. The arduino will collect data using the AVR, and pass it on to the Atheros chip which is running linux to send it to emoncms.
Re: Why not using the Raspberry pi directly for logging values
Hi
There is an all in one unit in the pipeline that places the Arduino directly on the Pi.
See the bottom of this thread: http://openenergymonitor.org/emon/node/3937
We are all eagerly waiting on its release. :)
In the mean time many of us have done a direct serial connection which does away with the wireless units.
Lionel