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

1. Building the Sensor Set (Core Module, Mini Battery Module, Sensor Module)

2. Connecting the Soil Sensor to the Sensor Set

3. Pairing the Sensor Kit with the Radio Dongle

4. Display temperature and humidity data in graph

5. Indication of exceeding limits on the LED strip

6. 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.