viehweger.org

The ELK on the Meadow

Hi Y'all,
my name is Ernst Viehweger, and but this is too complicated, just call me Murphy.

Here is my installation.
It's simply controling the irrigation for some trees. 360 at this time. Ok, the ELK is controling the house too and doing some normal security work: a lot door contacts, glass-breaking-sensors, smoke-detectors, the phone, the power etc. But this is normal, not worth to mention. Anyway:

During the last winter, the system had mainly the task preventing freezing of a small collection of exposed magnet-valves.
And the ELK-system managed this task very good too.

At this point, let me remark the following OT: all the world is talking big "the earth is heating up". But when you have a close look to the average and record-temperatures, you find (at www.weather.com) record high temps, which are several decades old, but record-low-temps which are only some years recent. And therefore a heavy frost is IMHO much more probable and dangerous as "the earth is heating up". At least for my ZIP-code 75644, maybe the only point on this world ...

Ok, this ELK is not watching a townhouse but a small farm.

The history: East Texas is also known as the green part of Texas. But not during the last years. In 2005 Rita & Katharina brought disaster to the shore, - and at least some penetration to NE-Texas, - which was nearly the only summer-rain in NE-Texas. But the summer of 2006 was rather dry. A lot of my trees died because they simply had no water. And even more dried back significantly, throwing them back for years. At this time there was only a timer for the X10-modules, an old CP290, which is a timer. With this, you cannot control anything on condition and also the remote control by phone is basicly possible, but expensive and uncomfortable. At least for me, because during the summer I'm staying in Germany. So a lot of shit happened and too much of the trees on my treefarm died, the well was running empty and as a result the waterpump died too. In former times there was an Atari-system, watching the farm & the house, but once there was a real strong thunderstorm and the controller of the Atari-HD quit. Due to the antique technic, such a HD was not available anymore. BTW this old system could only handle 12 inputs and 8 selectable I/Os. So I looked around and get HAI in my view. I invited myself and my wife to a presentation of HAI in New Orleans. Much informations at least for me, because I had no idea about security systems in the US. And also nice visiting New Orleans in 2004, - before the disaster. But it was not possible to get such a HAI-controller for a good price. So I found ELK with even more features for a much better price. For a short time, I also thought of an Ocelot-system or using Magic-Modules. But then I decided to the ELK-M1G. Today in 2007 I see: that was the right decision. The ELK-memoryspace for the programming is now used by 90%. And ELK-rules are very powerfull, easy to create, easy to maintain.

Back in 2005 I ordered an M1G at SmartHomeUSA.com, - and got one which obviously was returned before and (because? it) had a damage from any thunderstroke. But because I'm spending the summer and also Christmas im Germany, and only spring and fall in Texas, I noticed that, ... as the warranty was over. And here I must point out the service of ELK: they replaced me the precious part! That was more than usual service. Spanky is well known at www.cocoon.com as a very helpful guy. But at ELK, there seems to be a nest of those. Brad Weeks for example.

Back to my farm: Last winter I realized a small DIY-project: digital measuring the waterlevel in a 50ft-shallow-well. This is difficult, because it had to be reliable and the location attacs everything with corrosion. Now it is working. I also made some improvements at the watersystem. And the ELK-systems has some rules to handle all this. Now, as I turned the normal shallow-well with the ELK-system into a real power-well, - there is enough rain. At least until June 2007. But in NE-Texas, a dry season can start at every day and with the ELK-control, I'm armed.

In the future there is a lot to improve. But at first here some images:

On the meadow there are some irrigation-valves:
installing a valve
Here I'm just installing an irrigation valve

irrigation lines 

Here you can imagine the structure on the meadow: the covered line contains the controlwires and a thick waterline which is always under pressure. Across - every 20 ft - running irrigation lines, 10 lines. BTW all ditches are more than a mile.

inserted valve
Details of a nearly ready mounted irrigation valve

Some irrigationvalves are also in the carport
carport water distribution
The lightbulbs are only for heating, preventing freezing during the winter. They are controlled via an ELK-relay-output, not via X10. Why? Reliability. Freezing can cause a lot of damage. Of course, the box is covered during the wintertime.

In the pumphouse the watersystem:
waterpump system
And the ELK-control inside the pumphouse:
ELK-system open
In the past, all the X10-Universal Modules were controlled by a CP290, a dumb timer. Now the ELK is sending commands to a TW523/CP05, which is controlling the Universal-Modules. I took single modules so I could change defective ones more easy. In the future, the ELK system shall controll the irrigation valves direct via relais-outputs.

In the house -100 ft away - a substation:

ELK substation
Here at an early time. In between there are more wires. But even if there are more wires, much more substations are possible too.

And now the core: measuring the well-level:
It is a shallow well, 50 ft deep, nearly 3 ft diameter. The measuring tape has 2 tasks:
 
1. giving color, making it plausibel
2. moving the wheel with the magnets

The measuring tape has a swimmer on one end, a weight on the other. To hold the tape tight, the swimmer - an empty softdrinkbottle- is partly filled with gravel. These weights are fixed at the end of the tape with aircraft-safety-wire, which is stainless. The bearings of the wheel consists of white PVC parts, used for waterlines. The wheel is not turning on the iron thread, but on a PE-hose. The wheel consists of two caps, normaly used to close 4"-PVC-waterpipes, screwed together. On the wheel there are 2 alu-angles with screws #8 fixed, holding two opposite magnets also fixed with screws #8. SS and Alu will not disturb the magnetic field and also fight corrosion. The friction between the wheel and the tape is tested and sufficient. I also tryed notched solutions for the tape, but didn't find a good one, - and in this case, it is not necessary. There is no slipping. Just in case, the last two calibration-rules below will help.

water level measuring

When the waterlevel changes, the wheel turns and a magnet is moved in a distance of 1/8" to 1/4" over/across the 2 Reed-contacts. These contacts are mounted on an epoxy-cardboard, side by side, 1/2" to 3/4" away. They become closed when the magnet is near enough otherwise they are open. This counts the waterlevel. I call the two Reed-contacts A and B and both are necessary to determine whether the waterlevel is rising or falling.

Now the ELK-system count up or down -whatever happens- and this way it knows if the waterlevel is high or low, - or too low.

    Necessary for measuring are only the ELK-rules #1 to #8
    However I've added #9 and #10, just in case and for calibration
     
  1. WHENEVER Well-B(Zn6) BECOMES SECURE
      AND Well-A(Zn5) IS NOT SECURE - OPEN LOOP
        THEN SUBSTRACT 1 FROM Waterlevel(Counter2)
  2. WHENEVER Well-A(Zn5) BECOMES SECURE
      AND Well-B(Zn6) IS SECURE
        THEN SUBSTRACT 1 FROM Waterlevel(Counter2)
  3. WHENEVER Well-B(Zn6) BECOMES NOT SECURE - OPEN LOOP
      AND Well-A(Zn5) IS SECURE
        THEN SUBSTRACT 1 FROM Waterlevel(Counter2)
  4. WHENEVER Well-A(Zn5) BECOMES NOT SECURE - OPEN LOOP
      AND Well-B(Zn6) IS NOT SECURE - OPEN LOOP
        THEN SUBSTRACT 1 FROM Waterlevel(Counter2)
  5. WHENEVER Well-A(Zn5) BECOMES SECURE
      AND Well-B(Zn6) IS NOT SECURE - OPEN LOOP
        THEN ADD 1 TO Waterlevel(Counter2)
  6. WHENEVER Well-B(Zn6) SECURE
      AND Well-A(Zn5) IS SECURE
        THEN ADD 1 TO Waterlevel(Counter2)
  7. WHENEVER Well-A(Zn5) BECOMES NOT SECURE - OPEN LOOP
      AND Well-B(Zn6) IS NOT SECURE - OPEN LOOP
        THEN ADD 1 TO Waterlevel(Counter2)
  8. WHENEVER Well-B(Zn6) BECOMES NOT SECURE - OPEN LOOP
      AND Well-A(Zn5) IS NOT SECURE - OPEN LOOP
        THEN ADD 1 TO Waterlevel(Counter2)
     
    for calibration:
  9. WHENEVER WL+1(Task1) IS ACTIVATED
      THEN ADD 1 TO Waterlevel(Counter2)
  10. WHENEVER WL-1(Task2) IS ACTIVATED
      THEN SUBTRACT 1 FROM Waterlevel(Counter2)

That's all on measuring-rules. Now you can manage your irrigation time according the waterlevel noted in counter 2. This easy logic you can programm in any other language. Choose this principle for the luxery-controll of your garage door or whatever.

Is this a linear measurement? Yes and No: A calibration line of this equipment is linear from a distance, but a close look makes steps visible. Here the counter is using a range from around 30 to max 190. That's enough resolution and the steps don't matter in this application. For a higher resolution you only need the time & money for fixing more magnets and changing the numbers in ELK-rules, which are reading out the counter.

BTW: the same principle is widely used. For example: in former times volume control was made with variable resistors. But now the turning device delivers only an impuls-pattern (as in my application) while turning the knob. And a DA-converter delivers the right resistance. Today for volume control and much more, it is simply a counter, which is controling a decoder who is switching a resistor-matrix. No crackling anymore, even not in the cheapest carradios. Another indicator for digital volume control: there is no turning stop anymore.
And how is the scrollwheel on your mouse working? Now you know it!

--------------------------------------------------------------------
Not responsible for typing or other errors, nor other nonsens,
whatever happens with these not copyrighted ideas ;-)  July-01-2007
--------------------------------------------------------------------

Home (german language)

Seitenanfang | Impressum | e-mail