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| Dave, seen this? Grid overvoltage story in the Guardian |
| << < (5/6) > >> |
| wraper:
--- Quote from: Jeroen3 on October 21, 2024, 06:13:53 am ---What a weird article. They blame the voltage, but actually it's the at capacity last mile LV network. Most older network I'm, sure in AU also were laid out with a lower "typical household" load then today. --- End quote --- The issue is that although AU has 230V nominal instead of old 240V, all they did is put the new nominal number 230 V with high high side tolerance (+10% to -6%). So nothing changed in practice, but you're supposed to safely use 230V appliances. |
| tooki:
--- Quote from: wraper on October 21, 2024, 05:49:27 am --- --- Quote from: tooki on October 19, 2024, 05:48:36 pm --- --- Quote from: wraper on October 19, 2024, 04:38:08 pm --- --- Quote from: tooki on October 19, 2024, 11:09:07 am --- --- Quote from: tszaboo on October 19, 2024, 08:41:04 am ---I wonder what appliance uses less energy with less voltage? --- End quote --- Incandescent light bulbs I guess? OK, in fairness, old gadgets with linear regulated power supplies would burn off more waste energy as heat with higher input voltages. --- End quote --- Any resistive stuff, such as space heater, kettle, toaster, clothes iron, hair drier. --- End quote --- Those will use less power, but the same energy because they need to run longer. --- End quote --- Half of those are not even temperature controlled. --- End quote --- Yes, they are. The only one of those that isn’t temperature controlled is the toaster — but the user will have to toast for longer to get the color they want. Similarly, if someone is using an old-fashioned hair dryer without temperature control, they’ll need to run it for longer. |
| jonpaul:
IEC, NEC, UL and other utility spcs exist for the allowed limits on mains voltage. Normally a PSU/SMPS/consumer device has a band of acceptable voltage areound a nominal. https://www.power-sonic.com/blog/single-phase-and-three-phase-voltage-by-country/ In US the nominal was changed over the years 100>>110>117. Tolerance band can be 8,10,12%. Modern PSU topology includes a PFC that accepts any mains eg 70..260V and outputs a 360V DC bus with a boost PFC. Jon |
| tooki:
--- Quote from: jonpaul on October 21, 2024, 08:23:21 am ---In US the nominal was changed over the years 100>>110>117. --- End quote --- Nominal was never 117V. That was a labeling compromise between 115V and 120V, the latter of which has been the nominal voltage for nearly a century. |
| Berni:
Yep this is pointless. The biggest difference is for resistive heaters, yet most of those run on some form of thermostat. So the only thing remaining is appliances with high power brushed motors like vacuum cleaners, angle grinders etc.. that will be slightly less powerful. This most certainly will not make a 100$ difference in your power bill, even if you love vacuuming your rugs daily. Tho in general power companies try to keep the voltage cranked up because they are compensating for the voltage drop in the lines. They have a specified tolerance window of +x%/-x% so in order to have the best chance of staying in the window they crank it up on the high side so that more voltage drop can occur before it falls out of the bottom of the tolerance window. But the problem is the voltage drop is not always there during low load hours (also solar panels are becoming popular now) so you get the full voltage. Peoples electronic devices die because the engineer that designed it was instructed by the company to make the PSU cheap and not last too long out of the warranty period. If not that then it is a brief overvoltage event (storm or some line fault) that pulls live to 500V for a moment is what kills it, not something that would be any less likely if the AC voltage was smaller. |
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