Simple Electricity – Sit Class
This was originally to fall under Jokes but ended up here and some electricians can read this as well, especially those taking short cuts or those
private a__holes using “Speaker wires”
to cut cost in South Africa!!! (you are going to kill someone, hopefully yourself and
not your child)
Let’s call the height of the dam on the hill the Voltage (the Volts will stay the same with the only possible fluctuation depending on the water
level inside the dam)
The water coming from the pipe is the stream = Current = Amps
The tap is the resistor = ohms (by controlling the tap we control the flow)
Electrical energy usage are measured in watts, and watts are calculated by Volts x Amps = therefore the current we need for something to work in a
“AC:” (Found in buildings – most economical to distribute over distance)
If an appliance or piece of equipment is 3kw - 3000w we need
240V circuit = 3000 240 = 12.5Amps
110V circuit = 3000 110 = 27.27Amps
If the voltage drops the required Amps go up
The thickness of a cable or wire is determined by the Amps/current we are going to use in that circuit.
A Circuit Breaker (CB) is for the protection of the cable/wire to prevent it from overheating and fire (it is not to protect appliances or electrical
A bad/loose connection can result in tripping the CB and overheating normally at the point of the problem. This is due to the wattage of the
equipment asking more Amps from the circuit to perform correctly.
All electrical spares and equipment does have a lifetime and quality differ in price, but you do not need a Rolls Royce while the cheapest No-name
will cost you more in the end (made in ???).
The Earth Leakage:
Are for protection of life – in a AC circuit we need two wires; a Live and Neutral. If for some reason they draw different loads (unbalanced) the
Earth Leakage will trip (this means the amps are leaking somewhere)
When using an Earth Leakage you can sometimes find 2 neutral bars in a Distribution Box (DB). Make sure the wires run from the correct neutral bar.
The live wires from the Earth Leakage must have their matching neutrals from the Earth Leakage neutral bar only. Neutrals from elsewhere will
unbalance and trip it
Fault finding – remove all the neutrals on the specific neutral bar and start putting them back one at a time. Switch on/off between every wire you
put back. The one tripping it is the circuit with the problem. The quick way is by unplugging everything and see which one solve the problem - this
will however not high-light every problem like the neutral bar method. If you do not have the tools – do not F_ck around
”DC:” (Vehicles - batteries)
All I can say is that if you do not have the wiring diagram and/or some knowledge you will struggle. Make a small 12V lead light.
”Sound:” (Your powerful Low-Fi system is useless if not pure – distortion is not power)
Speakers do not work with Direct Current (DC). Make sure the wattage can be handled by the amplifier output or it’s bye, bye speakers – not more
or better sound. If you do not understand series and parallel connections ask someone with knowledge or burn your fingers.
As with speakers the amplifier output can blow if overloaded by the speakers – Again ask someone with knowledge
Normally an amplifier will specify the ohms and output power, and matching speakers that are of a 20% higher RMS value should work best. RMS is the
constant maximum wattage a speaker can handle not the peak power advertising gimmick.