SainSmart High Sensitivity Water Sensor for Arduino UNO MEGA R3 Mega2560 Duemilanove Nano Robot XBee ZigBee
Water sensor brick is designed for water detection, which can be widely used in sensing the rainfall, water level, even the liquate leakage. The brick is mainly comprised of three parts: An Electronic brick connector, a 1 Mohm resistor, and several lines of bare conducting wires. This sensor works by having a series of exposed traces connected to ground and interlaced between the grounded traces are the sens traces. The sensor traces have a weak pull-up resistor of 1 Mohm. The resistor will pull the sensor trace value high until a drop of water shorts the sensor trace to the grounded trace. Believe it or not this circuit will work with the digital I/O pins of your Arduino or you can use it with the analog pins to detect the amount of water induced contact between the grounded and sensor traces. Features :  Working voltage: 5V.  Working Current: <20ma.  Interface: Analog.  Width of detection: 40mm x 16mm.  Working Temperature: 10C-30C.  Weight: 3g.  Size: 65mm x 20mm x 8mm.  Arduino compatible interface.  Low power consumption.  High sensitivity.  Output voltage signal: 0~4.2V. Pin Definition :  "S" stand for signal input.  "+" stand for power supply.  "-" stand for GND. Applications :  Rainfall detecting.  Liquid leakage.  Tank overflow detector. Package Content : 1 x Water Sensor. 5 x Dupont Line.