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Seesaw soil sensor

Seesaw soil sensor

Information

Most low cost soil sensors are resistive style, where there’s two prongs and the sensor measures the conductivity between the two. These work OK at first, but eventually start to oxidize because of the exposed metal. Even if they’re gold plated! The resistivity measurement goes up and up, so you constantly have to re-calibrate your code. Also, resistive measurements don’t always work in loose soil.

This design is superior with a capacitive measurement. Capacitive measurements use only one probe, don’t have any exposed metal, and don’t introduce any DC currents into your plants. We use the built in capacitive touch measurement system built into the ATSAMD10 chip, which will give you a reading ranging from about 200 (very dry) to 2000 (very wet). As a bonus, we also give you the ambient temperature from the internal temperature sensor on the microcontroller, it’s not high precision, maybe good to + or - 2 degrees Celsius.

More information …

Setup

In order to use the Seesaw soil sensor use the following settings:

Mandatory

Hardware
Seesaw soil sensor

Types : moisture, temperature

Address
<I2C Address>
Ex: 0x49

Other settings can be found at the sensor setup information

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