Hi guys. So on mybb today there is a article that says City Power is switching off our geysers. This morning my sis was complaining that the geyser for the house only had luke warm water. It is a brand new geyser as the old one burst last week. We were going to call the plumbers that installed it today to come have a look ... but now I am thinking maybe city power switched it off during the night. At electric box for the house there are two geyser switches. The normal one and then another one with a funny name ... can remember it now. I think it is geyser relay switch or something. Is this what City Power uses to remotely switch geysers off? Dont want to call the plumbers for nothing.
They use a receiver in the form of a box of electronics.
The signalling frequencies in SA are 316.67Hz and 1050Hz. The latter can be noticeably heard on guitar amps and fluorescent light fittings.
The system is old, older than what I am.
In Roodepoort where I live, the injection plant aka transmitter is so old it is erratic. it slips timing and also fades with signal, which can lead to cold water i.e. receiver cannot turn load back on. This is especially true for very old electromechanical receivers. More modern receivers have timers to automatically reinstate the load. These receivers also cut the load when the frequency slips below 49Hz as would be the case if the grid is completely constrained.
They send a binary code down the mains by turning the signal on and off i.e. tone on = 1, and tone off = 0.
The true form of the binary code turns the relay on. The 1's complement of the binary code turns the relay off.
As for geyser failure, I have seen enough to know I would not touch a Kwikot with a barge pole. I am sure a Made-in-China product would exceed the current crop of geysers made in SA. They are all crap, they fail, they don't last. Gone are the days of cast-iron cylinders and decent elements, nowadays its all as cheap as possible.
