Experiment
Time: 10 min.
Description of the experiment
We will use the HARDWARIO Sensor Set kit to build soil moisture and temperature sensor. We will visualize the measured data in a graph in Node-RED. At the same time, the connected LED strip will give us a coloured signal if the measured values exceed the set limits.
As part of the experiment, we will understand:
How to measure soil moisture with a capacitive sensor
How moisture changes in different soil types

Experiment steps
Building the Sensor Set (Core Module, Mini Battery Module, Sensor Module)
Connecting the Soil Sensor to the Sensor Set
Pairing the Sensor Kit with the Radio Dongle
Display temperature and humidity data in graph
Indication of exceeding limits on the LED strip
Extra: controlling of the relay
Building the Sensor Set

Connecting the Soil Sensor to the Sensor Set


Pairing the Sensor Kit with the Radio Dongle
Open HARDWARIO Playground application - Tab Devices

Display temperature and humidity data in graph
Go to HARDWARIO Playground application - Tab Functions
Copy and Import this Soil Sensor Flow
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Click on Deploy

Open Tab Dashboard - you'll see gauges with Soil Temperature and Moisture.

Put your Soil Sensor in the jar to see changes in moisture and temperature.
Indication of exceeding limits on the LED strip
Pair Control Set with LED strip and Radio Dongle.
LED strip changes its color depending on values of the soil moisture.
In HARDWARIO Playground, tab Functions, you can change limits of moisture values (node LOW MOISTURE) and colors of the LED strip (node LED STRIP GREEN/BLUE).

Extra: Switching the relay
The imported flow contains the relay control function on the Power Module. In the LOW MOISTURE node, you can change the value at which the relay will switch on. You can use this function, for example, to switch on the irrigation system if low soil moisture values are measured.
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