I've been called may things, but capacitative isn't one of them.
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8 years ago
Very variable mains voltage
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8 years ago
With a 13v variation like that it would be very noticeable just with your lighting.
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8 years ago
Incandescants sure, not so sure about CFLs and LEDs. They are feed from (primative) SMPSU's and isolated from any variation in the supply voltage.
When we had our half volts incident the CFLs still worked but having been woken up and still half alseep not sure how much light they where giving compared to normal. Note that is with the supply at 120 V or so... not a mere 13 V variation.
During the high overnight volts period the only light that noticeaby changed was my desk lamp, incandescent, fed from the UPS. That happened when the UPS tripped into voltage reduction mode...
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8 years ago
All my lights are run off the UPS due to me losing so many LED bulbs from overvoltages. The electricity board claimed 253V is within tolerance, but the LED bulbs disagreed. I put the lights temporarily direct to the mains to see if I could notice, and the CFLs dimmed even more than the incandescents. I guess it depends how they're designed.
Anyway, I was phoned by a very helpful electrician this morning from the electricity board (well the company that deals with the grid anyway), who told me that the severe fluctuations coincided with them replacing a large transformer at a nearby power station, and while they were doing this they manually tapped up the other one to compensate. I'm not sure why that caused the voltage to gradually and repeatedly vary, but nevermind.
When I mentioned I've had overvoltages up to 253V now and then for the last two years, he said that they've changed the guy that monitors the 240V substations around here. The previous one made sure everyone got 240V, the current one just sets it within tolerance. Strange, as I used to get 240V all the time +/-1, now I get 240V-253V, so it's not a different setting, but something that's varying or not being compensated for.
He also told me that automatic tappers are not used on the 240V substations, only 11kV and above. He said they'd be changing too often (and presumably wear out?)
He also said if I notice an overvoltage enough for the UPS to care (about 250V+) more than half a dozen times in the next two weeks, he wants to know.