The Berlin grid was isolated from '48 until begin of the '80s. Berlins BEWAG was very proud of running a stable net on this island. They used a big bunch of energy storage devices: steam under pressure, batteries etc. to keep the frequency and phase stable. In begin/mid '80s they built a 380kV power line from West-Germany (Buschhaus) to Berlin crossing the GDR. So Berlin was hooked to the west-european frequency.
After the fall of the wall they disconnected this line and hooked up to then USSR driven east german grid. That was for commercial reason, reportedly they saved a Million Marks a day. So Berlin had the same grid frequency as Moscow, and many clocks on churches, towers, the city hall, public clocks on poles etc. ran on that frequency. The USSR grid had a much bigger limit on the phase, so the grid driven clocks sometimes lost or won 15min a day, as far as I remember. Sometime in the '90 they switched to the west-european grid for then reunified Germany. There were similar developments for other european satellite states of the USSR, i.e. Hungary. They had a long direct 750kV DC-connection, for a great distance you use DC. In '92 I visited the DC/AC converter in Budapest, installed in a rather big hall. It was cooled by de-ionized water, which was so aggressive to get ions that they could not use any metal for fittings but they had to use glass. In this big hall there was a fairytale castle made of glass pipes, tubes, coolers etc., very impressing. In the old times :-| Cheers Detlef Schücker "time-nuts" <[email protected]> schrieb am 12.02.2021 20:41:25: > Von: "Alex Pummer" <[email protected]> > An: [email protected] > Datum: 12.02.2021 22:39 > Betreff: Re: [time-nuts] Mains Frequency > Gesendet von: "time-nuts" <[email protected]> > > at the time I grew up in Eastern Europe -- "communist time" -- they kept > he clocks using the line frequency as reference -- by counting the > periods during the day and week and for longer time for equal time > interval the "provided" equal number of line frequency periods, as > longer the time interval was as more precise was the time. That way the > clocks were relative accurate. They could do it since everything was > "central governed". > > On 2/12/2021 9:24 AM, Lux, Jim wrote: > > On 2/12/21 8:23 AM, Thomas D. Erb wrote: > >> "I would think they try to hold it over 1 day, so that mains driven > >> > >> clocks don't run slow or fast.? That being said, I wonder how many > >> > >> clocks are still being built using a synchronous motor drive? Given that > >> > >> all the clocks on appliances in my kitchen have drifted apart, I'll bet > >> > >> they use their internal microcontroller crystal as a reference." > >> > >> Actually I think all of my kitchen appliances use line frequency for > >> time reference - it's so easy to count. > > > > > > Maybe.. you've got to condition the AC from the secondary side of the > > transformer and use a pin to bring it in on, which requires at least 2 > > or 3 passive components, and you already have a crystal for the > > microcontroller (thinking here of oven timers and the like, which have > > a numeric display). These applications are super price sensitive, and > > those 2 or 3 components cost money, in components, in board space, and > > in assembly costs. Pennies to be sure, but... > > > > And the fact that my appliances drift on the order of a minute in a > > month, differently. So maybe some count cycles and some have a rock. > > > > > > > > _______________________________________________ > > time-nuts mailing list -- [email protected] > > To unsubscribe, go to > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions there. > > > > > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time- > nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
