Information

The sensor comes coated with PRF202 - a moisture resistant varnish for electronics. It's
ok for play around in a flower pot but not enough for outdoor use. You must add an
additional protection to the whole sensor after soldering cable to it! Some
suggestions on making the sensor more robust after attaching the cable:
 Polyester or epoxy resin - this method is the most bullet proof as the resin is
totally resistant to the water. On the par side, note that sensitivity of the sensor
will decrease depending on how thick the layer you are going to apply. Also
applying the resin in uniform manner presents some challenge.
 PlastiDip - some of my customers have tried this method - easy to apply by
spraying and not a lot of loss of sensitivity.
 Rubber balloon - yes, just roll a long balloon over the sensor :)
Be sure to coat the whole thing - the sensor part, the electronics and the cable
connection itself so no bare copper or solder is accessible to the water.
Rugged version
Pre-coated version is available since December 2016. The sensor is coated in epoxy
resin, cured and additionally protected by adhesive-lined heat shrink. The 1m (3 feet)
long cable is pre-soldered. Light sensor is covered by heatshrink, so the light
reading will always report total darkness.
The pinout of the rugged version (with white cable):
 RED - VCC
 BLACK - GND
 BLUE or GREEN- SDA
 YELLOW - SCK
Shield is not grounded on the sensor end and must be grounded on the master end.
Stuff people did with it
 A review of several cheap soil moisture sensors available on the market: Testing
Capacitive soil moisture sensors
 A video from Growing Robot about using the sensors with Raspberry Pi
 A complete Open Source logging solution employing a batch of 40 sensors in
Crete * Smart and Safe Outdoor Plant Watering System
 Smart Watering Hardware
 Waterproof holder for I2C Soil Moisture Sensor
 Weather / Watering Cover for Chirp! Plant Alarms & Sensors
Drop me a message if you want your project listed here.