An RCD will provide protection against accidents, but we should not rely entirely on them. RCD's are considered to be additional protection under the definitions in the AS/NZS 3000 Wiring Rules.

RCD Laws for Residential and Rental Properties in wa

The use of RCD's with a rated operating residual current not <30 mA and a trip time <300ms, is recognised as providing additional protection in the event of failure of other measures of protection or carelessness by users could present a significant risk of electric shock.

RCD's are testable and resettable devices. They have a "test" button that when pressed it creates a small leakage condition and should activate a switch that disconnects the conductors cut the power to the devices in that circuit. If the test does not activate the switch then there is a fault and must be checked by a qualified electrician.


  • Requirements are for RCDs to have a maximum sensitivity of 30 mA.
  • RCD's with a sensitivity of 30mA are designed to operate before fibrillation of the heart occurs.
  • RCD's with a sensitivity of 10mA are designed to operate before muscular contraction, or inability to let go occurs. The use of a 10 mA RCD may be considered in areas of increased risk, such as circuits within a doctors and dental surgery (body protected areas), supplying outdoor equipment, bathrooms and areas such as kindergartens.

STS test portable and fixed single and 3 phase RCD's for visible damage, manual functionality, trip time, trip current at both phase 0° and 180°. Depending on the RCD type the test results must be within an acceptable parameter. The test data is then recorded and gives you an overview and condition of the RCD's tested.