Soil moisture sensor

Soil Moisture Sensor Probe Wiring Table

Bare Ground Red POWER: 3.3V to 20 VDC. Black OUT: (0 to 3V related to moisture content.)

Soil moisture (SM) Raspberry PI (RPI)

SM Ground -> Steckbrett -> Stecklitze -> RPI Ground SM 3.3 V -> Steckbrett -> Stecklitze -> -> RPI 3.3 V SM OUT -> Steckbrett -> Stecklitze -> -> RPI GPI

Homemade

http://gardenbot.org/howTo/soilMoisture/

galvanized steel wire -- 12 gage or equivalent (2 mm stahl draht) packing foam block (e.g. inside a product box for home electronics) -- the slightly flexible kind is better (less brittle than styrofoam) soldering iron and solder lead wires

TODO

Make image to text

Arduino

Create a lib/Config/Config.h

#define HOSTNAME "sensors.cloudcontrolapp.com"
#define BSSID "WIFI name"
#define PASSWORD "WIFI password"
#define NAME "Name of sensor"


ino build
ino upload

Compare

With FOM/mts - Field Operated Meter Date | this | FOM

2014-07-03 19:00 | 227 | 9% 2014-07-04 09:00 | 287 | 19,2% 2014-07-04 09:30 | 271 | 12,5% 2014-07-04 10:00 | 268 | 10,8% 2014-07-04 10:13 | 356 | 22,9% 2014-07-06 20:44 | 262 | 10,5% 2014-07-09 08:40 | 352? | 17,3% 2014-07-09 18:48 | 326 | 11,7% 2014-07-11 07:54 | 267 | 3,5% 2014-07-11 08:09 | 299 | 13,6% 2014-07-11 08:22 | 359 | 24,0%

First test calculation

http://www.arndt-bruenner.de/mathe/9/geradedurchzweipunkte.htm

         y2 - y1      24 - 68/5
  m  =  —————————  =  —————————  =  13/75
         x2 - x1      359 - 299

  b  =  y2 - m·x2  =  24 - 13/75·359 = -2867/75

Gesuchte Funktion:

f(x) = 13/75·x - 2867/75