So 6am one Wednesday morning I get a phone call from a home owner in Mosman. The customer tells me; “The power has all gone off and every time we reset the safety switch it won’t stay on”. “We have constant gas water heating and with no power the gas water heater doesn’t work either! Everyone is about to get ready for work and school and the hectic day ahead but there’s no power, it’s winter and cold and everyone is panicking!”

old safety switch board

This is what their power board looked like when we arrived

We turn up and firstly see that there is one safety switch for all the power circuits within this big two storey house and also one safety switch for all the lighting too. In short, this means that if there is a problem with any one power circuit in the house, the safety switch does its job and turns off!


The Problem is the safety switch controls ALL the power circuits and the second safety switch controls all the lighting circuits. In this case we managed to isolate the fault to the dishwasher. But because the entire house was tied to one safety switch, the faulty dishwasher made the rest of the power in the house inoperable. The same could happen also with the lighting circuits. There are over 70 Down lights and other lights in this one house. If any 1 of the globes or transformers in these lights was to ‘fuse’ or be faulty, the entire house would end up in darkness.


This is the newly upgraded "RCD Combo" safety switches when we finished

This is the newly upgraded “RCD Combo” safety switches when we finished

After this experience and the inconvenience caused, the owners opted to upgrade their electrical system and go with our solution of putting each individual power system and each individual lighting circuit on its own safety switch/ circuit breaker. This is called an “RCD combo”. RCD stands for Residential Current Devices and Combo, in laymen’s terms means having several of them. For most people this is what they call their safety switch to most people. With the Dishwasher now fixed, all is back to normal for them:-)


This is just one story from the field we work in everyday. And yet another happy and satisfied DCN Electrical customer.