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Introduction:
The fork-shaped probe with two exposed conductors, acts as a variable resistor (just like a potentiometer) whose resistance varies according to the water content in the soil.
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This resistance is inversely proportional to the soil moisture:
- The more water in the soil means better conductivity and will result in a lower resistance.
- The less water in the soil means poor conductivity and will result in a higher resistance.
The sensor produces an output voltage according to the resistance, which by measuring we can determine the moisture level.
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Features:
- Operating Voltage: 3.3V to 5V DC
- Operating Current: 15mA
- Output Digital - 0V to 5V, Adjustable trigger level from preset
- Output Analog - 0V to 5V based on infrared radiation from fire flame falling on the sensor
- LM393 based design
- Easy to use with Microcontrollers or even with normal Digital/Analog IC
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Applications:
- Optimise soil moisture for optimum plant growth.
- Accurate irrigation decicions.
- Demonstrate environmental management.
- Saving water and energy.