[time-nuts] Power lines and time

Poul-Henning Kamp phk at phk.freebsd.dk
Mon Aug 22 01:30:15 EDT 2005

In message <001301c5a6a2$74803840$0500a8c0 at darius.domain.actdsltmp>, "Bill Hawkins" writes

>Power companies bill on time-integrated power - watt-hour
>meters in the US. Watt-hour meters are still mostly driven
>by electric clocks, in a way. The frequency does matter.

Uhm, sorry, that is just plain wrong.  The Ferrantis (sp?) power
meter which is the most widely used meter in the world is not
frequency sensitive within a band of +/- 10% or more.

>1. It is unlikely that any power network just lets itself go,
>with no standard time/frequency to hold. The under-frequency
>relays would make that hazardous.

Does not follow.

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.

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