This is a self sufficient Arduino board, which is powered by harnessing solar power and using a 9V rechargeable battery. It is perfect for anyone who is interested in doing Arduino projects that do not require a computer or any power supply. You can take this to the most remote places for any project.
What you will need:
9V Rechargeable battery
Solar cells (About 11V)
1N4001 diode
100uf 10V capacitor
Arduino board
9V battery connector
Power connector (to connect to the Arduino board)
What you will need:
9V Rechargeable battery
Solar cells (About 11V)
1N4001 diode
100uf 10V capacitor
Arduino board
9V battery connector
Power connector (to connect to the Arduino board)
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Signing UpStep 1: Setting up the Arduino board
This is probably the simplest step (please use the schematic as reference for wiring before doing anything else).
Change the jumper of the Arduino board to "EXT"
Change the jumper of the Arduino board to "EXT"
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Adafruit has a tutorial on converting an Arduino Uno from 5v to 3.3v. There are loads of 3.3v Arduino designs about (including the awesome JeeNode, which fits in a medicine bottle and can last months on a boosted AA battery).
More important is the movement of energy potential. In an electrical circuit the High energy state to Low energy state moves from the positive terminal to the negative terminal. The electrons flow directly opposite of that to balance the energy between the positive and negative terminals.
When talking about flow, it's far more useful to use conventional notation because that is actually how the energy moves, even if it's not how the electrons move.
The electrons move in the opposite direction of the electrical energy, which means tracking electron flow is usually pointless.
That's why the conventional method is still taught in electrical engineering, and why the vast majority of books on the subject prefer the conventional method.
In semiconductor devices current isn't always carried by electrons - it can be carried by holes which have positive charge so the notion of a "correct" direction independent of the type of carrier is rather weak.
Engineers always use conventional current. I write as a retired electronics design engineer with a lifetime's experience.
Regards, Pete
The direction of the "flow of electricity," however, is an essentially arbitrary convention. Depending on the medium in question it may be most appropriate to understand what is going on in terms of electron flow (negative to positive) or "hole" flow (positive to negative) in, say, p-type semiconductors. In electrochemical circuits, the interesting portions of the circuit involve ion transport, not bare electron transport, in both directions at once, even for DC.
Conventional current, the flow of positive charge, is not an "incorrect" theory about which directions electrons flow. It is a very well established convention in electrical engineering. It is not wrong to use it.
See this page, for example, for more details.
As quoted from the first page you provided: Conventional Current assumes that current flows out of the positive terminal, through the circuit and into the negative terminal of the source. This was the convention chosen during the discovery of electricity. They were wrong!
It's a convention which is so universally employed that producing a circuit diagram with the arrows reversed would cause confusion rather than enlightenment.
Regards, Pete
would a 12v 200mA solar panel be enough?
konto89
Yes it does "smoothen" the flow of electricity to the batteries, as the electric output from a solar cell is not always constant. Here is a link that might help you understand more on capacitors :)
Greets
Nice Project.
But one question, how big should the Solar-Panel be to charge the battery ?
Can it also be to big and overcharge?
zerOne
It really depends on the voltage of your battery. Different solar cells have different ampere rating and voltage, so you would not something that is too powerful or too weak in comparison to your battery.
So, I have questions:
The only programmable chip I have any experience with is the picaxe system. Will this 'ible work for a picaxe board as well?
The one I own runs off 4.5V (3xAA batteries in a pack), so would I be correct to assume that I should replace the 9V cell in your circuit with 3 rechargeable AA cells?
Thank you very much. It is very useful.