I was wondering if anyone knew how the US power grids control their line frequency with respect to time ? There seems to be four separate grids - Eastern, Texas, Western and Quebec - but I have no idea how they get their time. Thomas D. Erb tde@electrictime.com<mailto:tde@electrictime.com> / Electric Time Company, Inc. Office: 508-359-4396 x 117 / Fax: 508-359-4482 97 West Street Medfield, MA 02052 USA www.electrictime.com<http://www.electrictime.com> [Facebook]<https://www.facebook.com/pages/Electric-Time-Company-Inc/127918073950854?ref=hl>[Twitter]<https://twitter.com/tower_clocks>[pinterest]<https://www.pinterest.com/electrictime/> [htmlsig.com]<http://www.electrictime.com/>

Hi, It's based on UTC, as derived from GPS. I think you will find the following NASPI report of interest: https://www.naspi.org/node/608 You will find maps over the regions too! While NASPI is PMU/synchro-phasor focused, older equipment use GPS too for phase capture. Cheers, Magnus On 04/04/2017 03:33 PM, Thomas D. Erb wrote: > I was wondering if anyone knew how the US power grids control their line frequency with respect to time ? > > > There seems to be four separate grids - Eastern, Texas, Western and Quebec - but I have no idea how they get their time. > > > > > > > Thomas D. Erb > tde@electrictime.com<mailto:tde@electrictime.com> / > Electric Time Company, Inc. > Office: 508-359-4396 x 117 / Fax: 508-359-4482 > 97 West Street Medfield, MA 02052 USA > www.electrictime.com<http://www.electrictime.com> > [Facebook]<https://www.facebook.com/pages/Electric-Time-Company-Inc/127918073950854?ref=hl>[Twitter]<https://twitter.com/tower_clocks>[pinterest]<https://www.pinterest.com/electrictime/> > [htmlsig.com]<http://www.electrictime.com/> > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. >