RCD Testing

There is no doubt that RCDs are brilliant devices which save many lives. The problem is like most electrical or mechanical devices, RCDs are prone to failure. Research has indicated that the failure rate in the range of 3-15%.

RCD’s work on the principle of ‘what goes in must come out’. Under normal circumstances, these two wires carry matching currents. In the case of an electrocution, a properly working RCD will detect the imbalance and act as a circuit breaker, operating (“tripping”) swiftly to cut the supply power. This can prove to be life saving, as even a small leakage current can cause a fatality if the leaking electrical current passes through a person. A current as small as 30mA (0.030 Amps) induced for a fraction of a second can be enough to cause cardiac arrest.

• The presence of moisture and contaminants
• Internal components become maligned
• The contact surfaces are disrupted causing ‘contact welding’
• Deliberate shorting out (to prevent nuisance tripping)

There are plenty of good and logical reasons why you should have your RCDs regularly inspected and tested. If you have gone to the effort and cost to have RCDs installed, it only makes sense to make sure they will save a life when called upon.

According to the Model WHS Regulations – January 2012, the installation and regular testing of RCDs is mandatory for all circuits protecting hostile equipment and/or environment.

Click here to download your copy of the Electrical Safety Code of Practice.

Click here to download your copy of the model WHS Act and Regulations

Primary Source – Safe Work Australia