Power usage

Yesterday, we had a bit of a scorcher.  117F.  The day before was 110, so a difference of 7 degrees.  Look at the difference in power usage.  It's absolutely nuts.

7 degrees translated into 2kw of power.  That's crazy.  Today will be even hotter, I'm sure it will be even nuttier.

Helpful Links

While writing all this automation code, I found tons of useful information out there.  I'll try to keep this post updated with some of the things I found that we especially useful.

Insteon Command Reference
AD2USB Forums (vista alarm panel interface)
One Wire FS
LibConfuse Documentation
LibEvent Documentation
BrulTech
Bitfield decoder
http://marc.merlins.org/perso/linuxha/
http://homewireless.org/wp/2010/03/insteon-commands/
http://irrigationcaddy.com/blog/
WMR968 Serial Protocol
http://hobby-boards.com/store/

Playing with sensors:

I've been goofing around lately with some one-wire sensors.  I have RJ45 jacks all over the house, and I've been wiring them into the one-wire hub, and getting temperature data on all the rooms.  The problem is, I purchased a bag of 25 raw DS18B20 chips, so I've been soldering the things onto little stub wires, and then crimping them onto rj45's and it takes forever.

Then I had the idea of just crimping the chip right into the RJ45.  It actually fits perfectly.  But I was worried that the data would be messed up, because it would basically be measuring the temperature of the wall, not the room.

So I crimped one stub, one 4" wire, and put them right next to eachother for awhile, and recorded the results:

 

The long wire is much more sensitive.  The way it jumps up and down, is actually the air conditioner going off repeatedly.  The stub seems to smooth the results out more.  It does seem however, that the stub is consistently about .5 degrees higher on average, so I guess that's the effect of the wall holding heat.  Based on these results, unless I need actual detail, these stubs will be fine, and are much easier to make.

This will eventually be the home of my journey through building a home automation system, from scratch.  I am DIY'ing everything, from the installation of all the hardware, right down to writing the software for it from scratch.

This week I've released the initial beta version of gnhast - Garbled's NetBSD Home Automation Scripting Tools.  Download it here.

About gnhast:

A collection of daemons that work together to build an event-based home automation system. The core set of daemons is written in C, however, any event (such as a light being turned on) can be handled by an external script or program. These programs can be written in any language, and the central daemon handles all the intercommunication. It is designed to be easily extensible for new device types and protocols.

The core system is BSD Licensed (3-clause), however scripts or additional data collectors may be written under any acceptable lic.

While the primary development environment for this is NetBSD, it can be used on other UNIX variants, such as Linux, or other BSD's.

gnhast wiki (in progress)

The initial version has support for one-wire sensors (temp, humidity, lux, lightning strike, general counters), Brultech GEM's, and Insteon v2 switches and dimmers.  Support is planned for NuTech AD2USB devices, and a few other things, as I buy and install them in my house. The general plan is to co-develop the system as I physically install devices, so more support will be added as my wallet allows.

Tim