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
HOW THE SOLAR STORE WORKS
There are a number of components and parts to the Solar Store, and knowing a
little bit about how a circuit works can help you to decide how to best use it in your
projects. Let's take a look at the three main parts of the board and what they do.
3V GND
3V
GND
1
2
3
4
5
D1
6
7
D3
Filling
Storage
Release
Filling Stage
A voltage from the Solar Panel appears at the board, and a one-way valve (1)
prevents damage to the circuit if the panel is wired up the wrong way round. The
voltage from the Solar Panel is then 'limited' (2) which converts it from the 10V
range of the Solar Panel, to the 5V range expected by the storage system.
Storage Stage
A super-capacitor (3) stores the energy. A sensing circuit (4) checks how much
energy is stored, and feeds this to the Level terminal, which can be looped over to
the Enable terminal to make the board self-operating without a micro:bit.
The level sensor can reach up to 5V but the micro:bit can only safely sense up to
3V, so the voltage is scaled into the range 0-3V for the micro:bit by scaling circuitry
(5). This needs power to operate, which is provided by the two power-in terminals at
the top, and the board power LED (D1) also lights up.
Release Stage
Energy is released by opening the supply valve(6), and this is done by applying a
voltage to the enable terminal. Finally, because the voltage might be up to 5V, it is
limited(7) down to 3V for the attached circuitry, and also lights LED (D3).
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