Saturday, August 24, 2013

Bootstrapping

My last posts on my old dead blog were documenting an atmega128rfa1 based wireless network I was building. The plan was to use Contiki OS. After I got the PCBs made and assembled (44pin QFNs with toaster oven reflow), I realized the software part was going to take a lot of work. Also the amount of effort it took to make such small, complicated PCBs was not worth it either. My interest in the plan decreased and my workplace got sold to another company. I decided it was time for a change of plans, and change in location.  Now fast-foward 2 years to today.

So now I'm in Phoenix, AZ, but my needs have changed. I still wanted to open my garage doors from my phone, but I also need to automate my pool. First step was to make a solar powered temperature monitor using an RF200 Synapse module, coupled with an Solar powered Wireless, Sensor Node kit and xbee2synapse adapter board. You can follow the temps on my Xively feed.  The pool_air_temp channel isn't really accurate as it is directly in the sun. It's hot here in Phoenix, but not that hot. I need to make a better case for it so the guts are shaded, but the solar panel is outside the shade. 

After learning all about pool maintenance at the awesome troublefreepool.com site, I decided to go with liquid chlorine system. Chlorine generators (salt systems) are expensive and with the hardness of our water (high calcium), I just didn't think that was a good way to go. People say they like the feel of a salt pool, but you can always add salt in a liquid chlorine system.  Chlorine tablet systems were highly discouraged in the TFP site as it will overload your pool with chlorine stabilizer (CYA). If you ever get into trouble with algae, I'm told it's nearly impossible to fix it when your CYA levels are off the chart.

During these summer months, I have to pour about 1 quart of 15% in every other day with 1 quart of acid once a week. I'm sure come fall the when the temps lower and amount of sunlight the pool gets lowers, those amounts will have to change. Thus my desire to digitally monitor these 2 chemical levels of my pool and automate injection of them to keep things in balance. 

I would also like to swap out the single speed pump with a variable speed (VS) pump to save on energy costs. On top of that, one day I would like a solar pool heater so I can get 3 more months of pool usage out here. I was kinda surprised when I learned that pool season is not 12 months here in Phoenix. The pool temps are really only enjoyable May-September. Evaporation and reduced sun in the fall/winter really causes it to cool down fast. 

I'm definitely learning pool equipment has crazy markups. Worst of them is digital automation controllers. Even a basic one that does just time of day pump on/off costs >$200. A "decent" one will set you back $1k. The guts of those things are relatively simple......

Since my post is going long, I'll stop here. Next episode I'll post some details about the automation system I'm about to build. Synapse wireless modules to the rescue! 



2 comments:

  1. Thanks for the note over at my blog. Good luck with your projects, it'll be fun.

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  2. Michael, great post. I enjoyed the links and hope to learn more on pool automation. Thank you. I just bought a variable speed pool pump (Intelliflow) and found out my current Arduino project won't work with my relays that I just purchased a month ago. I was using a relay on the old motor pump, but the new motor will only allow the On/Off factory setting, and not the advanced variable speeds and features unless it communicates via RS-485 cable and knowing how to communicate with it. I am hoping to build a simple way to turn on my pumps and lights from around 25 feet away and also hoping to use my Arduino to do so.

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