• Residual Current Devices

    Residual Current Devices (RCD’s) in WA – Why, What, When, and Where

    29 Mar, 2017 | 186 views


    In Western Australia, the Energy Regulations 1947 were amended in 2009 to require that when a residential property is transferred, leased or hired, the owner must ensure that a minimum of two Residual Current Devices (RCD’s) protecting all power points and lighting circuits, are installed. There are significant fines for those that fail to comply. All new homes from 2000 required RCD’s to be installed.


    RCD’s monitor the flow of electricity from the main switchboard and prevent electrocution by cutting the electricity supply if an imbalance in the current is detected.  Current RCD’s will normally be able to cut the power within 10 to 30 milliseconds. By installing at least two RCD’s, the property’s circuits can be divided evenly.  This ensures some light and power remain if one RCD operates and also minimises faulty operation from appliances which have low-level leakage current.  All properties constructed from the year 2000 should already have two RCD’s fitted.

    When – Homes for sale

    At least two RCD’s must be fitted to protect all power points and lighting circuits before the land title is transferred.  If you are planning to sell your home and it does not already have at least two RCD’s protecting all power points and lighting circuits, you will need to engage a licensed electrical contractor to fit two RCD’s to the main switchboard or distribution board.

    When – Renting a home

    Landlords must arrange for at least two Residual Current Devices to be installed on the switchboard at their rental premises.  If RCD’s are not fitted then tenants should contact the managing agent or landlord and request that two RCD’s be installed.

    Where- Number of RCD’s

    ​The regulations require two RCD’s be installed on the main switchboard.  In some cases, to reduce the number of circuits affected by the operation of any one RCD, homeowners may consider having more than two RCD’s fitted. There are limits on the number of circuits that can be directed to an RCD hence there may be a requirement in some properties to have more than two RCD’s.

    Testing the Residual Current Devices

    ​All RCD’s have a test button which should be pressed every three months.  Pushing the test button simulates an earth leakage fault and indicates whether or not the RCD is operating correctly.  Electric clocks and timers will require resetting after each test.

    Testing beyond the test button on the RCD unit requires a Licenced Electrician.


    Penalties of up to $15,000 for individuals and up to $100,000 for a body corporate may apply if the regulations are breached.

    Who can Install RCD’s

    Only licensed electricians are qualified and permitted to install and test (beyond the test button) RCD’s.

    How much does it cost to install an RCD safety switch in Perth? 

    Prices start from as little as $200 – $300 each (supplied and fitted).  Costs do depend on the type of electrical box installed at the premises as the RCD must fit correctly and be compliant.