The live wire on a switch carries the current that originates from the main power supply, and goes through the switch before reaching the bulb.
Take a look out our guide to wiring up a light switch so you know what process a professional takes to complete the job.
Turn off the main power supply and ensure the electricity is cut off from the switchboard by turning on a light.
Remove the board and unscrew the switch to be replaced.
Note the colour of each wire connected to each pin in the old switch and attach each wire to the new switch accordingly.
Mount the light switch to the board and reinstall it on the wall. Turn on the power supply and try switching on the new switch.
Under this method, the light switch’s wires are connected to the existing circuit, so the light draws electricity from the current circuit while having its own switch. It is similar to the parallel circuit and highly preferred due to less wiring involved.
It demands vast wiring behind the switchboard, hence least preferred. The idea is to connect two switches to the same light bulb, allowing the users to turn a bulb on/off from two different locations.
Various law restrictions in different states for handling the electrical work are:
A person installing, touching, repairing, modifying, connecting or disconnecting wires must possess a valid electrical license. Merely supervising another person also needs a permit according to NSW fair trading. Violating the rules will attract fines up to $22,000.
According to Worksafe Queensland, any DIY electrical job (wiring and or rewiring a light switch) is illegal, inviting penalties of up to $40,000. Performing an electrical task exposing a person to a risk of death or serious injuries attracts fines up to $600,000 (if an individual) or $3,000,000 (if a corporation) in addition to five years of imprisonment.The South Australian State Government urges people to hold an SA trade licence, training, and a certificate of compliance.According to Energy Safe Victoria, changing light switches on a site is marked illegal, inviting up to $5,000 penal charges for individuals.Tasmania is governed by Service and Installation Rules and Occupational Licensing Act 2005, restricting unqualified personnel to carry out electrical wiring work. NT Worksafe has similar restrictions.In Western Australia, the government asks every licensed electrician to provide an electrical safety certificate to the clients within 28 days. In New South Wales, you will need to hire a professional electrician.A neutral wire on a switch is not necessarily connected directly to the bulb. Instead, the wire runs through a connector block and then reaches the bulb. The source of a neutral wire is the main power supply, running directly to the bulb (it does not go through the light switch).
The live wire on a switch carries the current that originates from the main power supply, and goes through the switch before reaching the bulb. The switch, when turned on, allows the conductivity by joining the live wire within itself with the help of a thin metal sheet (sealed inside the switch).
Ground wire runs together with the live wire originating from the switch, meaning one end connects to the bulb and the other to the switch's pin. They are called “2-core+ Earth” cable.
Australian colour codes for wires.
Type | Colour |
|---|---|
Live or active | Brown |
Neutral | Light blue |
Earth or ground | Green/Yellow |
Phase 1 | Brown |
Phase 2 | Black |
Phase 3 | Grey |
L1 and L2 are the terminals on a light switch. A one-way switch will have only L1 along with C (Common), while a two-way switch will have L1 and L2 along with a C terminal. Some switches come with L1, L2, L3, and L4 terminals. All these terminals indicate the state of the light (on/off). In a two-way switch, L1 means off only when the L2 is on and vice versa. The common terminal wire originates from the main power supply heading to the light switch. L1 and L2 wires will run to the light bulb completing the circuit. When the bulb is turned on, L1 will represent the ON state, and meanwhile, the L2 terminal will represent the OFF state. Similarly, when the bulb is off, L1 and L2 will mean ON and OFF, respectively. Please note that connecting a bulb with a two-way light switch means there will be a total of two two-way switches. The L1 terminal will represent the same state in both switches all the time. A wire should run through both the L1 terminals of the switches before connecting to the bulb. Similarly, another wire should go through the L2 terminals of both the switches, finally connecting to the bulb. The common terminal will connect both the switches, ending at the second two-way switch.
When a bulb is wired backwards it will not cause an issue immediately. The real problem will initiate once the bulb is switched on. Wiring backwards causes reverse polarity. Bulbs have small metal tabs in them that generate light from electrical energy. Backward wiring will direct the electricity to the lamp’s sleeve (the outer portion of the lamp). As a result, the bulb may or may not turn on, and if a person touches the bulb (from the sleeve, obviously) will get an electric shock. The wires may get hot and a tester screwdriver should be used to check the possibly conducted bulb sleeve instead of touching it directly after wiring or rewiring. Incorrect wiring will not create an issue inside the switchboard. The bulb's sleeve will become hot and might leave permanent damage to the bulb if turned on with incorrect wiring for a long session. Correct wiring is hence essential for ensuring a neutral bulb outer portion. Incorrect wiring will start a fire only if the wires get too hot, which is unusual even in the case of faulty wiring.