How does the electricity supplier turn Tariffs on and off
A device called a Load control Relay (or more often today an Electronic meter) is installed by the electricity supplier into your main switchboard This device is controlled by messages sent down the electricity lines. A message is sent to switch the relay on and another message is sent to switch the relay off.
For those technically minded types among us, a harmonic frequency of 50 Hertz is injected on the neutral. The relay changes state according to the frequency. This will sometimes cause a fluctuation in dimmed lights at the time the frequency is being injected into the network.
For more information Contact Electricians Plus now.