Instructions
Table Of Contents
- Introduction
- Parts
- Using Alligator Clips
- Solar Board Reference
- Project 1 – Sun Finder
- Project 2 – Garden Light
- Project 3 – Self Charging Cooling Fan
- The BBC micro:bit
- Getting Code to Run on the micro:bit
- Project 4 – Adding an Energy Meter
- Project 5 – Energy Logger
- Connecting Up
- Code for the Energy Logger (MakeCode)
- How it works
- Connecting to Your PC
- Pairing Your micro:bit With MakeCode
- Showing the Device Console Graph
- Capturing Data From a Charge and Discharge Cycle
- Downloading Data
- Getting Data into a Spreadsheet Program
- Analysing the Data
- Graphing the Data
- Results
- Understanding the Data
- Understanding Duty Cycle
- How the Solar Store Works
- Project 6 – Intelligent Cooling Fan
- Troubleshooting
- About the Author
- Learning
- Monk Makes Kits
TROUBLESHOOTING
The Bulb is not lighting – make sure you have enough charge stored in the Solar
Store, as the Bulb has a minimum turn-on voltage. Also make sure you have
connected the Enable signal of the Solar Store. Check that the Bulb is connected
the right way round.
The fan is not turning – the motor used in the fan is quite low power, but it is not
as low power as the bulb. If you have checked all the advice above about the Bulb
and it still does not turn the fan, try harvesting more energy into the Solar Store
before you enable the fan.
The charge% reading never changes – make sure you have connected the 3V
and 0V pins at the top of the solar charge board to the associated pins on the
micro:bit.
The Solar Store is taking a long time to charge – try to find a brighter light
source, such as going outside and using full daylight or sunlight. Also try different
types of lighting indoors, LED lighting and tungsten/halogen lighting provide
different amounts of harvestable energy.
The Solar Store doesn't work very long – the Solar Store can only store a limited
amount of energy before it needs recharging, and it won't store large amounts of
energy like a battery might. Also if the equipment you attach draws more power
then it will discharge much more quickly. The secret to getting the best from an
energy harvesting system is to arrange for enough time to harvest the energy, and
use low power equipment attached to the output pins.
The micro:bit sometimes ejects the drive when running for a long time – use a
shorter USB cable.
The console/graph in MakeCode isn't working – check that you have the latest
firmware loaded into the USB interface chip of your micro:bit by following the
instructions on this support article:
https://support.microbit.org/support/solutions/articles/19000019131-upgrade-the-
firmware-on-the-micro-bit
My Solar Store lasts forever – if you are in very bright sunlight, it is possible that
there is enough harvested energy to simultaneously charge your Solar Store and
power your fan. Try the experiment in the shade, if this is the case.
You can also get general support about the micro:bit device from the Micro:bit
Educational Foundation support pages here: https://support.microbit.org
Page 38