Kitronik Prong Soil Moisture Sensor for BBC micro:bit

The Prong soil moisture sensor mounts to a BBC micro:bit (not included) with 2 prongs to monitor moisture present in soil. Any water or moisture in the soil will conduct to give an analogue voltage that can be read by the BBC micro:bit.

Prong is powered from the 3V supply of the BBC micro:bit. Use either the USB or JST connector on the BBC micro:bit to power the circuit. Prong and the BBC micro:bit can also be powered from the Mi:Power board to create a compact stand alone unit.

The board has been designed so that the BBC micro:bit can be bolted on using 3 x M3 nuts and 3 x M3 screws. Place the screws through the P1, 3V and GND holes of the PCB and BBC micro:bit, then use the M3 nuts to fasten together on the back of BBC micro:bit. Alternatively croc-clips can be used to connect between the Prong and the BBC micro:bit.

If using the Mi:Power board then additionally connecting P0 means the BBC micro:bit can sound an alarm if the soil becomes too dry.

When fitted to the Prong moisture sensor, the micro:bit can be coded via any of the micro:bit editors, such as the Microsoft MakeCode editor.

The Kitronik Prong is also used in one of Code Club Australia's Moonhack 2020 projects. You can get a water pump here, and a relay to automate watering.

Note: To ensure that the Prong moisture sensor has a long and fulfilling life, it is better to write your code to perform a moisture check every so often rather than continuously. When the check is performed continuously it promotes rapid erosion of the electrodes.

Features:

• Measure soil moisture levels.
• Attaches directly to the microbit.
• Use in conjunction with the Mi:Power board to provide power and an audible alarm.
• Code with any microbit coding editor.

Contents:

• 1 x Prong Soil Moisture Sensor for microbit.
• 3 x M3 Hex Nuts.
• 3 x M3 Countersunk Screws.

Dimensions:

• Length: 68mm.
• Height: 53mm.
• PCB Thickness: 1.6mm.

Requires:

• 1 x BBC micro:bit.

Resources:

• Datasheet.
  
• Instructions for attaching to the micro:bit