Safety Switch Faults
Faults in electrical wiring can cause serious problems such as fires or electrocution. Common causes of electrical faults are poor connections that over heat, faulty appliances, overloading, rodent damage, water egress, poor installation or damage to the electrical system.
3 Basic Faults
Short circuits, Earth faults and Overloads.
A short circuit occurs when an active wire and a neutral wire come in contact with each other, when this happens a large current flows causing the protective device to either blow (fuse) or trip (circuit breaker).
An earth fault occurs when an active wire comes into contact with the earthing system. Similar to a short circuit, a large amount of current flows in the circuit causing the protective device to operate.
Overloads occurs when too much load is applied to a particular circuit causing the protective device to disconnect the circuit.
Overloads and Short circuits are not overly difficult to diagnose. On the contrary an Earth Leakage fault is another story all together. Earth leakage is when a very small amount of current leaks from either the active or neutral circuit to earth. In South Australia that generally means any leakage that exceeds 30 milliamps. In the early days of Earth Leakage Circuit Breakers we often had one Saftey Switch covering most of the electrical installation. Which meant cumulative currents from a number of appliance could combine to cause an earth leakage fault even though each individual device would pass the portable appliance test criteria. As time moved on we started to see more than one safety switch installed in most home. As of December 2018 all circuits will have to be individually protected by a safety switch.
All oven elements are hygroscopic, meaning they absorb moisture. The new regulations will mean the number of earth leakage faults will go up significantly.
We hope the above information helps you understand some of the reasons earth faults can be time consuming to pin down. And that having a fixed price helps to allay some of the worry that goes with open ended hourly charges.