Welcome to number three in this series. Again If this is NOT appropriate please let me know I dont want to be known as the Sheldon of Grey Nomads. I trust you all had a great xmas and are watching the boxing day test or the yachts.
If you need electrical work done on your caravan or RV, get a qualified electrician or auto electrician to do it. Do not ever attempt it yourself, this stuff is dangerous and can kill you!
Where does electricity come from and how does that work?
Lets start simple, a battery (chemical)
A battery or cell is a source of DC voltage, within this description there are two major types, rechargeable and not rechargable. Electricity is produced by a chemical reaction within the battery producing an excess or surplus of electrons (the negative beasties) at one pole and a deficiency of electrons (more positive protons than electrons) at the other pole.
In a battery, electrons flow until there is no more potential difference ie. one pole is the same potential as the other.
In rechargeable batteries the charging electrons re establish the chemical situation in a charged state.
A power station (magnetic)
Faraday discovered that when there is movement between a conduct and a magnetic field a voltage will be "induced" into the conductor and a current will flow if there is a circuit.
In our power generators a rotor in the generator (keeping it simple) with many conductors is moved in a magnetic field, producing our electricity. In nuclear power stations, the reaction produces high pressure steam which turns a turbine connected to the generator (not my honda).
Solar
As caravanners and grey nomads we use this a lot. I admit I dont know a huge amount about solar and invite respectful correction.
In REAL simple terms the solar panel is covered with semi conductor cells that turn highly excited photons from the sun, into small amounts of electricity, when all these cells are joined together they produce enough to charge our batteries on a bright day. The amount of electricity produces is of course depending upon how bright or clouded the day is. I am told ambient temperature also has an effect on the amount of electricity produced.
Pressure (or for the purists, piezoelectric)
In days gone we listened to records played by a turntable and tone arm. Some of those tone arms uses a crystal glued to a needle that produced minute amounts of electricity by the pressure produced by the grooves on the rotating record (yes, I had lots of those).
Of course now days we listen to CDs and computer files (mp3 etc) on specialised equipment.
Today we will find a piezio crystal in electronic bathroom and kitchen scales. Of course there are other industrial uses of this technology.
There are a number of other devices that produce electricity, including fuel cells, friction (static) etc. For the sake of simplicity these will not be discussed.
Please remember what I am trying to achieve here. It is only to present a very basic background to electricity. I am still trying to work out what depth I will discuss AC and semiconductors (it will only be diodes). I will keep the maths to a minimum. I only want laypeople to achieve a basic understanding.
Thanks for the feedback so far, I would like to hear from you regarding how worthwhile or other, this exercise is.
I have just been surfing youtube for a simple battery video. this one is good.
www.youtube.com/watch?v=CX84l5ZZHVg
This one explaine piezo a bit better
www.youtube.com/watch?v=ACsy6xSIBm8
-- Edited by Crockie on Friday 26th of December 2014 06:26:37 PM
-- Edited by Crockie on Friday 26th of December 2014 06:32:29 PM
1 Cell will produce about 1.2v, so a string of them say 15[1.2 + 1.2 +1.2 +1.2 .... till you have 15] will produce 18v
Each string will produce a current of X dependent on the square area of the Cell, so the bigger the Individual Solar cell in the panel the more current that will be produced..
In a common size Panel cells can be generally about 100-125mm, some of the newer Solar panels are getting to 140mm+
So in general you will have say 125mm sized cell which give you about 1.5A to 2.2A dependent on the quality of the cells..
The number of String's of Cell will give you the final Current..
Generally this is between 3-5 string's..
So a panel will be in the area of 18v @ 6A - 11A
Hope this does not confuse the issue..
Juergen
__________________
IF I say something Dumb.. Just Smack me..
I'm full of Knowledge.. I don't profess to know EVERYTHING, but I'm constantly Learning new thing's..
Cheers for that Juergen, as I said solar is not my forte. Hope you had a great xmas mate.
BTW, this is exactly what I wanted to achieve here. Anyone with a respectful correction or low key addition (keeping technical information as simple as possible) is welcome to contribute. This is a way we can all help in this presentation.
Cheers
-- Edited by Crockie on Friday 26th of December 2014 12:04:52 PM
I am a bit thick I know but I have not found how to "follow" this thread.
Aussie Paul.
Each new topic starts a new thread. If you wish I will add them back to back on one thread, so you can hit the subscribe button and get the flow on (I think).
