Slashdot Mirror

Nice! I also did an over-the-top solution a few years back: http://www.kondra.com/circuit/circuit.html The write up is a bit old at this point as I've replaced the boards with custom hardware that uses a true meter grade chip per circuit so I get everything including power factor with certified billing grade accuracy. Nice setup though... kudos to you!

First off, I have to say I agree with the original poster... I too tried to use the Zenith stuff from Home Depot when replacing lights for a friend and the stuff simply doesn't work. Pretty disappointing since there isn't much to this stuff. When I started looking into doing lights for my home I also looked at the X10 stuff but finally decided to build my own infrastructure. Not that there is anything wrong with the X10 stuff... it's affordable, easy to use, and has lots of software support. However, I'm building some custom home automation stuff anyways (such as asterisk integration and a cross platform graphical data-flow language for microcontrollers so you can embed control logic onto a cheap controller board instead of using a dedicated pc without needing to know how to write code) so I figured I'd customize the motion stuff as well. I found some GE motion sensors for about $10 that work great (and actually come with docs covering sensetivity, range, effective angles, etc... which you don't normally get in a packaged unit). I modified them a bit to add tamper detection but otherwise they work great out of the box. These feed back into a controller board which can also control the flood lights (which are just standard floods controlled by relays). And yes, I'm sure all this can be done with X10, I just prefer to build my own stuff (http://www.kondra.com/circuit/circuit.html).

I read about a great solution some time ago, but I couldn't remember where. It might have been here, it might have been digg. Regardless, I found the link with the google query "power monitoring system"

http://www.kondra.com/circuit/circuit.html

It's very involved and detailed and it looks like anyone who tried to replicate the system would have to spend quite a bit of money, but then you'd have access to all of the data you could ever want about your power consumption.

I'll include the last page of the linked site here, just for your own edification:



Wisdom

So what did I learn from this project that I can pass on to other folks crazy enough to try this?

        * DON'T MESS WITH HOUSE WIRING UNLESS YOU KNOW WHAT YOU'RE DOING!

        * While my software was sort of overkill, I've got to say that having high resolution historical data for every circuit in my house has been very informative.

        * Keep in mind that when it comes to friends and family, 'informative' is a relative term. Although you might find it very 'informative' to know that your wife left the lights on in the living room three out of four nights last week, she will probably not think so. I've found it better to save my geek points for things like "honey, don't you think we should have a raid server?"

        * Just because you know how your electric bill breaks down now, don't expect to see any great savings. In my case most of the power went to my computer stuff. I will say that as a result I've rotated out some older dual cpu servers for lower power single cpu boxes and have tried to consolidate server functionality quite a bit.

        * If you know modbus and you don't need something quite as sophisticated as what I put together, the Veris board has a bunch of features built in such as alarm levels, etc. For a simple home system, this can make the software part of things quite a bit easier.

Here is a site that has made me excited about monitoring the power usage in my home:

http://www.kondra.com/circuit/circuit.html

this guy knows exactly how much power he's using:
http://www.kondra.com/circuit/circuit.html

Not sure what your point is. If you're saying that Slashdot was six days late to the party, well, yeah, surprise surprise. But if you're saying the guy just aped a Make hack and then got it posted on Slashdot, no. The guy who wrote the article Make blogged is the same guy who wrote the Slashdot story you're reading right now. Both link to

http://www.kondra.com/circuit/circuit.html

p