I’m part of an artist’s cooperative – The Flying Monkey Arts Center. Susan and I share a space there – her stitch lounge and my fledgling electronics space, Antitronics, which my brother and I are starting. More on Antitronics in later posts.

We’re trying to get a handle on utility bills at the monkey. It’s safe to postulate that a large part of the consumption is air conditioning (we’re in Alabama) and lighting. The lighting is fairly efficient flourescents, but they are switched in large areas so that in order to light one artist’s space, you have to turn on a lot more than you need.

One of the things we’re planning to do at Antitronics is teach some workshops on topics including arduino projects, basic electronics, etc. It turns out that from a previous project, I already have three precision 600 Amp clamp-on ammeters, and a conditioning board so that they can be read by simple A/D converters. So naturally, this has become a project to help monitor our power use and demonstrate what’s possible with a few available component parts. I have all the parts now, and will start lashing them together as I have time. They are:

• An Arduino Diecimila
• An Adafruit Xport shield
• A Lantronics XPort module
• My custom signal conditioner board
• (3) Fluke clamp on current probes
• A power supply (TBD)

Disclosure – soon we’ll be selling some arduino and related kits at Antitronics.

So what we’re going to end up with in an industrial-strength three phase tweet-a-watt.

I haven’t used the XPort devices before, and I had a good look at the manuals tonight. It’s an impressive device, and I can see more projects in the future using them.

I’ll post some photos and schematics of the signal conditioner board as soon as I can. It was built as a one-off project and I’ve lost the schematics, but it’s simple and I can reverse engineer it in a few minutes. As I recall, it requires -5V and +12V supplies, but that doesn’t matter so much. I’m just going to have to package it all well enough that the building electricians don’t balk when I ask them to add it to the panel feeding our floor.

I expect that it will be possible to tell pretty easily where we’re using a lot of power. The activities in the cooperative are pretty scheduled, and the A/C is only run on certain days, so I can correlate a lot of that manually. And it just occurred to me that the air conditioning units are near the power panels, so perhaps I’ll add a temperature sensor in the outlet of the A/C.

Since it’s an art space, I also plan at least one realtime display, to raise awareness of power consumption.

I’ll post updates here as I progress. This is a ‘as I have time’ project, so it may take a few weeks.