Switchboards

Common Problems with Switchboards

RCD and Overload Protection Devices

• No RCDs – without safety switches, your switchboard provides absolutely no protection against electric shock. Safety switches are the only device that provide protection to humans, and the electrical system in your home is unsafe without them
• Single RCD protecting multiple circuits – when there is only a single safety switch in your switchboard, it means that all the connected circuits will trip every time it detects earth leakage, which may affect power to your entire home! It also increased the chances of nuisance tripping during normal operation
• Malfunctioning RCD – safety switches that aren’t operating correctly may cause nuisance tripping, or may not operate at all in the event of a fault which is a safety issue
• Old style fuses – fuse boards do not usually have safety switches, and so they provide no protection against electric shock. They are also harder to maintain and create a risk of electric shock due to exposed live parts when replacing fuses. These old style fuse boards are no longer compliant and the switchboard must be upgraded

Fire Seal, Cracks and Signs of Heat

• Signs of heat stress – blackened insulation on cables or protective devices can be an indicator of electrical arcing or overloading. This could be due to poor installation or under-sized cabling, and is an immediate fire risk
• Not properly fire sealed – regulations require all switchboards to be properly fire sealed. This prevents fire from spreading to other areas of your house if it starts in the switchboard
• Asbestos – Asbestos was used in switchboards throughout Australia until the 1980s because of its fire-resistant properties. Due to the disastrous health consequences, asbestos is now a banned substance. Asbestos that is crumbling or requires disturbance for works/maintenance must be safely removed by a licensed asbestos removalist
• Damaged switchboard – if any of the protective devices or the switchboard enclosure is cracked or damaged, there is a risk that it could expose live electrical parts

Location and Labelling

• Inaccessible location – switchboards must be easily accessible in case of emergencies, cannot be located too high (main switch must be within 2m of the floor), or in cupboards where things could be stacked in front of them.
• Non-compliant location – near bathrooms or pools (due to the moisture) or too close to a gas meter
• Not weather rated – must be appropriately weather rated to protect the switchboard from the elements
• Incorrect labelling – Non-labelled or mislabelled circuits in your switchboard mean your circuits cannot be identified. This is a safety hazard to anyone who might need to turn off power in your home. The switchboard must also contain labels to indicate the Main Switch, the location of the earth electrode, as well as all solar devices.

Cable Sizing and Earthing

• Under-sized cables – cables are sized according to circuit capacity, so a circuit that is drawing more power requires a larger cable. Under-sized cables can cause overloading of circuits, leading to nuisance tripping, power outages or even a fire.
• Protective devices not properly rated to cable size – if the protective devices in your switchboard are not the correct size/rating for the cables, there is a risk that the device will not operate in time to prevent overheating of the circuit. This creates a risk of fire.
• No earth cabling – earthing is required on all power, lighting and appliance circuits. Without earth cabling, protective devices will not operate correctly. The fault will keep occurring undetected in your home, which creates a fire risk as well as a risk of electric shock.
• Light fittings not earthed – older homes may not have earth cabling to the light fittings, which creates a risk of electric shock if there is exposed metal in the fitting