How the electric circuit works

Ever wonder how the electric circuit works, the circuit is an uninterrupted loop that allows electrons to flow from one point to another. Firstly the electric circuit needs a power source, this could be in the form of a battery or generator. We use copper conductors to connect to our load device that will also need a switch to turn the circuit on and off. When the switch is in the closed position it allows current to flow to the load device known as a closed circuit and when in the off position, current is interrupted and the device fails to work, this is known as the open circuit.
Short circuits are also known types of electric circuits, this circuit can be dangerous and forms when the positive and negative conductors collide with one another. This can cause serious harm to the conductors and load devices.

In our homes electricity to your power outlets and lighting points are supplied from TPS copper cabling through a protective device called an RCD/RCBO. The TPS copper cable has 3 conductors, live, neutral and earth.

The Live Conductor – its the conductor that carries electric current to your load devices
{appliances}. Its current is dependant on the size of conductor and protective device.

The Neutral Conductor – the neutral is the return path for current after it flows through the load and its the reason why a circuit is complete. This conductor should have zero potential meaning 0 volts.

The Earthing Conductor – the most important cable in a circuit in my view, it provides a safe path for current to flow in the case of circuit malfunction. This cable will be connected to the metal frame of appliances, lighting fixtures and other known devices. A fault to earth will occur when leakage current leaks from the live conductor causing the protective device to trip and open the circuit.

The Difference between Current ,Voltage & Resistance

The movement of electrons which causes an electric charge produces electricity in the electric circuit. The continuous movement of electric charge through the conductors of a circuit is called current and is measured in amps. The driving force behind the current flow is called the voltage and is the difference in charge between two points, it is measured in volts with a symbol V. We always have opposition in the electric circuit and its called the resistance. The resistance opposes current flow and the higher the resistance the less current flows.

So the relationship between voltage, current and resistance is expressed by the Ohms law calculation – Current {I} = Voltage {V} / Resistance {R}

Increasing the voltage in the electric circuit will increase the current and increasing resistance will decrease the current.

A water pump system is a great concept of the electric circuit and current flow. In the electric circuit a power supply will create voltage similar to a pump producing water pressure in a pipe. The current will be identical to the rate of flow of water with the pressure acting as the voltage and any restrictions in the piping will represent the resistance. The overall resistance in the piping will depend on the length, the size of piping and the same applies for a conductor, the longer the length the more resistance you will have, the larger the cross sectional area of the cable, then the lower its resistance.

Whats the best conductors and insulators for electricity?

Electric current flows freely in a conductor and does not in an insulator. Conductors are usually made from metal which has a low resistance so current flows more freely, copper, aluminum, silver and gold are all classed as good conductors. Insulators are made up of non-metallic material that will slightly or completely block the flow of current, they have a high resistance material to electric current and good examples of non-metallic materials are rubber, wood and plastics.

The cables for powering your power outlets and lighting points are made up of copper material for conductivity and rubber for an insulator to completely block current from leaking. Current will always take the path of least resistance hence the reason we use copper as a conductor and rubber as a solid insulator.

What is a short circuit

The short circuit is the most damaging kind of fault you can have on the electrical circuit and you would be hoping your protective device quickly isolates the circuit before damaging appliances or any other devices.

A short circuit occurs when 2 cables or any other conductive material cross paths, this creates a shorter path for current to flow and causing large amounts of heat to be released from the cable. This heat can be quite damaging on the cable and could possibly result in causing a fire if the protective device is not brought into action. The protective device most commonly used in our homes today is called the RCD and protects the cabling when a fault occurs.

Km.electric always advise on testing your RCDs on a monthly basis, RCDs can be tested by pressing the test button on front of the RCD.

If a short does occur in your home or business, be rest assured km.electric is here to help. Call Ken on 0405 838 383