A few tips from DIY Drones

I visit regulary DIY Drones, and two posts lately captured my attention because they are directly related to our project:

  1. Dronepedia: The first issue is the necessity of having a well done wiki for any Open Source project. A solid wiki would spare users a lot of time and many replicated discussions. I think it is time for the Open Energy Monitor to have a solid wiki, and the team here agrees on it. I guess we will roll it very soon. Needless to say, help is much appreciated.

  2. DIY electronics warranties: A serious issue for the DIY movement businesses, and small electronics makers in general. Where does your liability stop, and where does users responsibility begin? As Anderson puts it in his post, it varies from one company to another, while they are committed to delivering a minimum level of customer and technical support, other companies estimate that starting the moment where you power the components on, their liability stops. It is quite paradoxal indeed. I invite you to read the linked post ans share with us your opinions in the comments

A great talk by Saul Griffith on energy

A fantastic video:

Can we make this kind of analysis and sustainable energy plan at the community-group scale?

It would be really exiting to integrate the electricity energy monitoring hardware directly into such tools so that the larger context of energy use is easy to see.

Rearranging builds upon

I made a start on rearranging the builds upon page, I'd like to elaborate on the different ideas that the project builds from:
  • sustainability
  • open source design
  • personal fabrication
and explore the larger open source sustainable technologies ecosystem that is out there.


A few more designs:

- mains ac module
- multiple input pulse counter
- baseboard
- barebones CT Pulse RF unit

+ some example module connection diagrams at the bottom:

Next step is to order the components to test a few of these.

PCB Designs in development

The plan

Create a PCB's for each module that interconnect via standard 3-wire and 4-wire connectors. A PCB specifically for:

  • Mains AC v3 module
  • RTD Temperature sensing module
  • Relay module (may be able to use modules available for this)
  • multiple input pulse counter
  • Compatibility with the nuelectronics datalogging board.

Develop a baseboard that is an Arduino with normal shield headers but also with 3-wire and 4-wire connectors on the same PCB.

Develop a baseboard that is an Arduino with normal shield headers, 3-wire and 4-wire connectors and also tri-state buffer for master/slave network operation.

An barebones arduino with a CT or pulse input module and RF transmitter socket all in one.

Sampler 2.0

I wrote this program a while back, its an update to the VISampler program. When building the energy monitor its sometimes useful to be able to see the AC Voltage and Current waveform that your monitoring. It puts my mind at rest to know that the circuit is doing what it should: no large noise or over voltage spikes.

Main features

  • Select arduino from USB port drop down list
  • Take samples at different sample rates
  • Select any analog input or multiple analog inputs
  • See a zoom-able, pan-able graph.
  • Get Mean and Standard deviation of sample
Download it here Sampler 2.0

Kirikou: an open electricity monitor

Hello everyone,

This is my first contribution to this blog after months of reading it :)

I am Amin, I study a Bsc. of "Environmental and Resource Management" at the BTU, and I am currently doing an internship at the technical department at Wagner und Co. Solartechnik in Marburg.

My main task in this internship is to dimension and design photovoltaic systems for our clients overseas, and I could not help but notice how pricy the existing monitoring solutions are: more than 400 euros for a box that monitors your inverter's production and makes the data available on the internet. So I started thinking about building a system that does that for a very "affordable" cost. And since I have caught the Arduino virus for quite some time (Wired magazine's fault), I started to think about making an Arduino-based photovoltaic plant monitor, this is how I found the open energy monitor initiative.

Months of browsing and thinking made this little idea grow in my head like a good cancer, and talking to people about it generated mostly positive feedback.

I am now determined to launch a commercial product (DIY-Drones business model, more or less) that is based on the open energy monitor. This device, which I name for the moment Kirikou, will monitor the mains AC that comes from the meter to the distribution box in each building, plus 5 to 20 sub-circuit consumers. It will not require the intervention of an electrician (clip CT's). It will send the data to Pachube or Google Charts via Wifi. And it will cost 200-240 euros per unit.

Quite an ambitious target I know, but with the help and support of the inventors, the community and some other people, I am confident that I can make it take off. Open source hardware businesses started to pop up like mushrooms the last years, and that's fantastic! It is only fair to share the knowledge about things, it is a win-win situation for everyone and I really hope to see many businesses based on the open energy monitor.

There are also some unconventional ways to get it started, like these sponsoring programs that help entrepreneurs get on their feet in the beginning. A very good friend sent me this link to the Zurich HUB fellowship, and I applied.

I thought it would be in the spirit of the competition to get a community involved, and I created this Ulule page (screenshot below) to raise 120 euros to build my electricity monitor based on the Blackwidow board.

I am really excited to start this adventure with the support of a community, I believe that we could develop and spread this together.

I believe the first step should be to get more organized and communicate more efficiently on the technical choices and so on.

Your feedback, comments, criticism is most welcome, you can also visit my blog if you want to know me better.

By the way, the verdict from the Zurich HUB will be announced on Dec 20th (in a few hours), please wish me good luck :)


Networked Arduino's

Back in August this year, Ken Boak, Suneil and I had a build session where we developed networking for Arduino's. The documentation page still in the making can be found here:

I added a build example using the network for my home energy monitoring system with examples for an ethernet enabled master unit, PV monitor slave and Solar Hot water controller + energy monitor. All that can be found here:

Networked Solar hot water controller, Solar PV monitor and Home Electricity monitor