Safety Switches
Circuit Breaker & Surge Diverters versus Safety Switch
Safety switches are often confused with circuit breakers and surge diverters. As such, its imperative to understand the differences –
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Surge diverters protect the property from voltage surges such as those resulting from a lightning strike. The surge diverter captures the voltage spikes in the wiring within the unit itself which would otherwise be transferred into the equipment within the property.
Surge diverters do not act as a safety switch for personal protection resulting from electric shock
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Circuit breakers provide short circuit and overcurrent protection such as when a power point is overloaded.
Circuit breakers do not act as a safety switch for personal protection against electric shock.
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Safety switches monitor the flow of electricity through a circuit and detect a problem which may pose a risk to personal safety and turn the power off within 0.03 of a second.
Always remember, safety switches are not a substitute for common sense!
Safety switches always have a test button and have 30ma written on them. They are also sometimes labelled with the words “safety switch”.
How does a safety switch work
An electric shock can occur through direct or indirect contact with a live electrical conductor, such as everyday household appliances. During an electric shock, electricity usually flows through the body to earth.
The electricity can flow through the heart resulting in disruptions to the electrical impulses which are responsible for the heart beating, causing the heart to stop.
Current leakage to earth (residual current) through the body will be detected by the safety switch (ie the safety switch detects the difference (or loss) in current from the circuit) resulting in the safety switch disconnecting the power within 300 milliseconds minimising the risk of electrocution and fire.
For new domestic premises and where additional outlets are added to circuits, under the AS/NZ Standards 3000:2000 (Wiring Rules), socket outlets and lighting circuits are to be protected by safety switches (RCD’s) having a rated residual current not greater than 30mA.
Safety switches save lives in most situations, however they may not in some cases.
Safety switches operate by detecting a residual current. If there is no residual current, such as when physical contact is made between an active and neutral conductor, the safety switch will not operate.
Safety Switch Tripping
If a safety switch has tripped and cut off the power, it may be that the fault was temporary or due to lightning. Resetting the safety switch should restore the power.
If the safety switch does not reset due to a faulty electrical appliance or wiring, switch off and unplug the appliance which may be faulty.
Any faulty electrical appliances will need to be repaired by a suitably qualified person.
If the safety switch does not reset after unplugging the appliance, call a licensed electrician to find the fault.
Testing the Safety Switch
Check each safety switch every one to three months by pressing the TEST button to make sure that it is still working. This should trip the safety switch immediately. If the safety switch does not trip, call a licensed electrician.
If your home does not have any Safety Switches installed call Glen Clark & Co now for an obligation free quote or use our “Quick Quote” link to obtain an estimate now.