Perhaps we should have explained ourselves a bit better on Wednesday, hopefully this will make it clearer.
Electricity comes through the lines in your street. If these lines go down or are faulty nobody gets electricity.
The electricity leaves the pole and comes along a 'service line' to your meter. If this service line is faulty only you do not get electricity.
At the meter there is a 'ripple relay'.
Your electric hot water cylinder is wired to this ripple relay.
The ripple relay is controlled by the lines company.
The number one problem with a ripple relay is that it get's stuck in the off position not letting electricity through it. Usually it is sealed to prevent you from turning it on when it is controlled.
When the ripple relay is set to 'off' no power goes through it.
The reason you open it yourself is that it takes 4-6 hours to get someone out there to check it for you and to do precisely what you can do right there and then. Don't take no for an answer, when the person comes out they can reseal the box.
Monday we'll look a bit more at some of the other common faults that can occur.