Musings of a Home Automation Techno-Geek!


Active Member
How I Got Involved In Home Automation
Why My WAF Is So Low, I’m Always In The Doghouse!

I’d been a fan of remotes and other things MALE for some time, and I always was a techno-geek-kinda person even way back. I’m not the techno-geek type that does things just because you can, although I have been known to take the Rube Goldberg approach on occasion. Then again, Home Automation (HA) still IS a Rube Goldberg approach in many areas…

Although I had dreamed of HA on many occasions, it all actually started in my second apartment in South Florida. I wanted to wake up to the traffic report on TV, to see what route I’d take into work in Miami, and what that would do to my day after the drive (hehe). I’m not the kind of person that needs or uses an alarm clock. Unless I’m extremely tired, I wake up 5-10 minutes before they go off, anyway (only to punch the snooze and go back to bed!). I had computers hanging around – I had run several BBS and was a PC- and network-literate person (being in IT helped that) – so I looked for computer-based HA packages. Of course I got the IBM Home Director for a sweet deal. After all, this was an apartment and all I could do was use plug-in modules, and maybe replace a light switch to be taken out later. So the X-10 stuff with the IBM Home Director was good enough.

I got a VCR and a composite monitor and set them up in my bedroom, up on a shelf above my desk facing the bed. Then, I figured out what TV station had their traffic report at a specific time each morning, tuned the VCR into that one, and set up the computer to turn on the X10 module to the VCR and monitor at that time, and off again 10 minutes later.

Worked like a charm! I was hooked! I added a lamp, a couple other lights, and some small appliances. Then I found Homeseer, the product that did more than I thought possible at that time. I used it for a while and finally plunked down $40, I think it was, and registered it. Now I had the best computer-based extensible HA system available (in my opinion).

When I bought my house a couple years later, I already had plans to automate much of the lighting and what other systems I could. However, the first priority was the sprinkler system, which was missing its “gutsâ€. The conventional timer and valve system had been ripped out and never replaced. The lawn needed watering badly, and I didn’t own a hose! I couldn't see dragging a hose around weekly, so I bought a 24 volt transformer and the valve assembly, hooked it to an appliance module, and programmed a six-zone event in Homeseer. The six-zone event is simply turning the appliance module on and off over time six times, one for each zone in my ratcheting valve system. The duration was calculated based on the zone’s flow rate – I collected a half-inch of water over 30 minutes, and each zone overlaps adjacent areas, so 30 minutes per zone is 1†of rain over the entire lawn. Voila! It worked, and still works, great!

I always wanted to add some logic to the sprinkler system so that I didn’t water the lawn if it didn’t have to. Did I mention my $prinkler system uses city water? Gound water has iron and minerals stains the houses here - a no-no. Driving in the rain by homes and medians while sprinklers based on timers were running seemed like a complete waste of water and money. At first I was going to get weather info from the Internet from a nearby airport and use that for my data, but I found that rain is spotty in South Florida and I’d need something at my home to show actual data at my home – not some three miles away. We could get an inch while the airport got a tenth of an inch. It’s just the way the clouds form in Florida.

So I decided to get a weather station and put it up locally. I wanted the 1-wire station, but by the time I decided on a weather software package and got the funds available, it was no longer being made. Instead, I got an Oregon Scientific weather station with a rain gauge, Virtual Weather Station (VWS) software, and looked into the types of calculations I’d need to handle proper lawn watering – evapotranspiration, rainfall, humidity, sunlight, etc. These calculations were far too complex and I didn’t need anything that exact, so I developed my own formula based on observation and local conditions. I found that I didn’t really need to water the lawn more than three times a week, and as long as we got an inch or so of rain I could skip one of those waterings. Interfacing to VWS was done through its daily.txt log files, and I programmed Homeseer in VBScript to schedule or reschedule waterings (an event) based on nightly calculations of rainfall for the last three days. A script was born! I later simplified this even more, running the script only three times a week instead of letting it have free reign of the scheduling. This was done during a water shortage period where we could not water the lawns more than three times a week.

It has continued ever since and the lawn is almost always green – only insects cause dead spots now. But I have a plan for that, too. I’d like to get a liquid injector system so that I can inject fertilizer and insecticides into the sprinkler system. I just have to select the gear, install it, and put it under HS control.

Oh, without the budget and time limits just think of the ends to which HA can go!

And I'll stop there for now. More next time!
That's a great post Gordon, keep up the good work! I have never heard of the liquid injector system before, now that you have explained it I am really eager to put in my own sprinkler system next year.
I'll probably use something like this product - no need for power:

I have to check the various parameters in my system and the types of fertilizer and insect repellants I want to use. And although they don't show a check valve on the incoming water supply side, requirements here specify a check/relief valve between the sprinkler system and the water supply - since my water is supplied by the city, we don't want any checmicals getting back into the lines from low pressure or reverse flow. Similarly, we have relief valves on the hose spigots, too.

I already have those relief valves on my system, but I'd double the check valves so there was one on the supply side of the injector system, too. I have to check what the various plumbing codes are surrounding this application.
I looked into something called a FertiGator brand liquid fertilizer. I think it's like $150 or so which is basically a solonoid connected to the sprinkler water supply and a container of liquid fertilizer and then a control box to meter the proper amount of application.

I am wondering if they are using the venturi principle to inject (draw in) fertilizer into a pressurized water system. Not sure if they somehow pass the high pressure water into the "top" of the fertilizer or not. Can't remember how they do it.