Hi, my names Catherine and my husband and I would like to share with you some very helpful information that not many people know about the safety switches, how they protect their homes and families.. With four beautiful children of our own we are very passionate about keeping them safe and all our extended Landmark family (YOU!!) aswell. First well explain exactly how they work and the importance of both having them installed and regularly tested.
How does a Safety Switch work?
An RCD (residual current device) or more commonly known as a safety switch protects by constantly monitoring the current flowing in the live and neutral wires supplying a circuit or an individual item of equipment. Under normal circumstances, the current flowing in the two wires is equal. When an earth leakage occurs due to a fault in the circuit or an accident with the appliance or equipment, an imbalance occurs and this is detected by the RCD. As a result it will automatically cut off the power before injury or damage can result.
All current no matter how small can be harmful and its the safety switches ability to trip in just milliseconds which prevents any serious harm from occurring. So you understand just how dangerous the smallest amount of fault current is here is a small example and the effects such a fault could have on our bodies.
So taking in consideration an average kettle/ toaster uses 3 – 10 amps the results below show the effects of mere milliampere’s of current passing through your body for just a second.
- 0 – 0.5mA Generally this current is below the level of perception, resulting in no reaction.
- 0.5 – 5mA Although no dangerous physiological effects, this current may produce a startle effect
that results in injury due to falling etc.
- 5mA – 10mA Same effect as above but in addition muscular reaction may cause inability to let
go of equipment. Once current flow ceases letting go is then possible.
- 10mA – 40mA Severe pain and shock as current value increases. At currents over 20mA the victim may experience breathing difficulties with asphyxia if current flow is uninterrupted. Reversible disturbance to heart rhythm and even cardiac arrest is possible at higher values of current and time.
- 40mA – 250mA Severe shock and possibility of non-reversible disturbances to the normal cardiac cycle, referred to as ventricular fibrillation. The possibility of fibrillation increases as current and time increase. It is also possible to experience heavy burns at higher currents in addition to full cardiac arrest.
Do I need to have my safety switches tested by Landmark’s experts!
The simple answers is YES, Here at Landmark Electrical we perform under AS/NZS 3760:2003 annual
manual and Trip time tests under the required service intervals. In most cases a manual trip test must be
performed every 6 months by yourself. This simply ensures the safety mechanism within the device is still
operational and will shut off. We follow this up with a Trip Time test every 12 months. We at Landmark
Electrical then provide a PDF documented report on all test results on completion.
In short why test RCD Safety Switches
RCD Safety Switches form part of the overall requirements under the “Duty of Care” and the responsibility under the Occupational Health Safety laws and yes Safety Switches do perform part of the mandatory safety requirements. However without regular maintenance they may not trip in time and or worse not work at all.
We hope that you found this information as helpful as we have in making a informed decision in protecting your family.
Keep an eye out for our next post on the importance of a good earthing system and how it works with our safety switches in keeping you and your family safe.
If you need an expert out to ensure that your home is safe, get your favourite husband and wife team out to your home. Click here to book your electrical appointment today.