- #36
Baluncore
Science Advisor
2023 Award
- 15,558
- 9,311
My filament lamps never failed in 10 years. They must have been very old lights because they were significantly red-shifted, well back towards the introduction of electricity. Then the power authority, as compensation for increasing demand in the valley, raised the voltage by moving up a few taps on the transformer that fed my road. Filament lamps could not handle the overly-increased voltage in expectation of more customers. I had no choice but to move, as my lease had expired.sophiecentaur said:I really would like to know what is going wrong in my houses (this one and the last one).
My new location was purchased with a dedicated 11kV to 240V pole transformer. The voltage was OK, but in hot weather the lights would flicker and I had block periods of RF noise on the line. That noise was a real nuisance at antenna farm. The problem disappeared if I plugged in a load like a 2kW electric heater, so I fitted steep RF filters on my side of the power meters and put up with it. But the 11kV overhead lines still radiated phased spikes of RF all along the road, to the accompaniment of the wandering clicks of the district's electric stock fences, and the 19'th harmonic of the local LF air navigation beacon, very recently extinguished in favour of GPS.
Over a couple of months the line fuses to my transformer dropped several times, so the authority finally replaced the transformer. Turned out that, an internal nut on the 11 kV primary connection had not been tightened properly. That poor connection had arced and produced the voltage spikes that eventually took out the insulation. It was then RF quiet, and the newfangled CFL lights, (the early RF quieter ones, with the internal ballast transformer), did not flicker at all.
Power prices climbed, so cheap and noisy light-weight, (how much does light weigh?), switching CFL replaced all the older lamps. Then along came PV with grid tie inverters. Now the RF noise floor has grown like grass on the spectrum analysers, it is continuous in this world full of switching converters. During the same period, processor speeds have moved from 3MHz to 3GHz, and there are many more of them. There is now a certain and secure place for spread spectrum techniques and digital receiver technology.
At the moment, my PV keeps me slightly in credit, but the power authority plans to significantly drop the price they will pay for my excess PV energy next year. The network charge is greater than my power usage, so I guess the next change will be off-grid, to 12V DC LEDs, powered from PV and battery technology.