Comments by "Alan hat" (@alanhat5252) on "Technology Connections" channel.

  1. Electricity supply in Great Britain (not UK, Northern Ireland is linked by DC & takes it's frequency from the Republic of Ireland) is surprisingly variable (similarly with 25 tied countries in Europe). The figure the grid is fussed about is frequency, it's legally 50Hz ± 1% but normally ± 0.2% & adjusted overnight to reduce the inaccuracy over 24 hours to a remarkably small margin (there's nominally 4,320,000 cycles in a day) so you can use mains-tied clocks & timers reliably, although the European network has lost 6 minutes since 2018 due to a lack of supply in Serbia. Current is limited by your equipment, starting with a 100A fuse on the incoming supply (varies by supplier). What does vary is Voltage, the specification is 190V...264V & it varies continually, usually around 230V...245V depending what the grid needs to do to keep the frequency steady.
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