Hi, Has anyone experimented with measuring the net frequency? (50Hz in Europe, 60Hz in the USA) Me and a friend are trying to do this as accurate and precise as possible. His solution can do that with only a 0.0006Hz error, mine sofar does +/- 2Hz. Deviations of max. 0.150Hz are allowed (according to https://www.mainsfrequency.com/ ) so 2Hz is useless. I tried the following: - use the hardware comparator of an AVR328 (Arduino Nano) together with a 10kHz clock-source and then count the number of external clock-ticks between 2 falling edges. - I used something like https://www.botnroll.com/en/outros/4301-230vac-voltage-sensor-for-arduino.html to make the 230V into a 5V (DC) sine wave and connected that to D6 of the Arduino. D7 is connected to a voltage divider to get a 2.5V voltage reference (should be the zero-crossing voltage of the 230V input). - connected a PicDiv from Tom (a PD03) to an OXCO and the other end to pin D2 (ext interrupt) of the Arduino. +/- 2Hz (that's 80PPk right?) is way too much. So i'm curious if someone has a suggestion on how to improve this? Regards, Folkert van Heusden. p.s. the source code is at https://vanheusden.com/permshare/50hz.ino

On 2/27/23 11:23 AM, folkert via time-nuts wrote: > Hi, > > Has anyone experimented with measuring the net frequency? (50Hz in > Europe, 60Hz in the USA) Tons of folks on this list.. Check the archives..  But I'm sure folks will weigh in.  The hardware is always changing.

A few years ago I talked with Prof. Liu at Univ of Tennessee. She and her students had measurements all over the USA. Here is an interesting recent paper of hers: https://par.nsf.gov/servlets/purl/10234030, which has references to still other papers. Her bio at the end tells a little more about her activities. > On Feb 27, 2023, at 2:23 PM, folkert via time-nuts <time-nuts@lists.febo.com> wrote: > > Hi, > > Has anyone experimented with measuring the net frequency? (50Hz in > Europe, 60Hz in the USA) > > Me and a friend are trying to do this as accurate and precise as > possible. His solution can do that with only a 0.0006Hz error, mine > sofar does +/- 2Hz. > Deviations of max. 0.150Hz are allowed (according to > https://www.mainsfrequency.com/ ) so 2Hz is useless. > > I tried the following: > > - use the hardware comparator of an AVR328 (Arduino Nano) together with > a 10kHz clock-source and then count the number of external clock-ticks > between 2 falling edges. > > - I used something like > https://www.botnroll.com/en/outros/4301-230vac-voltage-sensor-for-arduino.html > to make the 230V into a 5V (DC) sine wave and connected that to D6 of > the Arduino. D7 is connected to a voltage divider to get a 2.5V > voltage reference (should be the zero-crossing voltage of the 230V > input). > > - connected a PicDiv from Tom (a PD03) to an OXCO and the other end to > pin D2 (ext interrupt) of the Arduino. > > +/- 2Hz (that's 80PPk right?) is way too much. So i'm curious if someone > has a suggestion on how to improve this? > > > > Regards, > > > Folkert van Heusden. > > p.s. the source code is at https://vanheusden.com/permshare/50hz.ino > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe send an email to time-nuts-leave@lists.febo.com

I use the CCP module in a 16F628 PIC microcontroller. Measuring the time for four cycles of the mains and then calculating its frequency. My version gives a resolution of about 0.002Hz, but by changing the number of cycles, clock frequency etc. this can be tweaked for even higher resolution In the UK the frequency variation is allowed to be an absolute maximum of +/-0.5Hz, beyond which automatic load shedding kicks-in. This happened on 9 August 2019 when two near-simultaneous failures occurred on the National Grid. https://www.ofgem.gov.uk/sites/default/files/docs/2019/09/eso_technical_report_-_final.pdf Andy www.g4jnt.com On Tue, 28 Feb 2023 at 05:14, Demetrios Matsakis via time-nuts < time-nuts@lists.febo.com> wrote: > A few years ago I talked with Prof. Liu at Univ of Tennessee. She and her > students had measurements all over the USA. Here is an interesting recent > paper of hers: https://par.nsf.gov/servlets/purl/10234030, which has > references to still other papers. Her bio at the end tells a little more > about her activities. > > > On Feb 27, 2023, at 2:23 PM, folkert via time-nuts < > time-nuts@lists.febo.com> wrote: > > > > Hi, > > > > Has anyone experimented with measuring the net frequency? (50Hz in > > Europe, 60Hz in the USA) > > > > Me and a friend are trying to do this as accurate and precise as > > possible. His solution can do that with only a 0.0006Hz error, mine > > sofar does +/- 2Hz. > > Deviations of max. 0.150Hz are allowed (according to > > https://www.mainsfrequency.com/ ) so 2Hz is useless. > > > > I tried the following: > > > > - use the hardware comparator of an AVR328 (Arduino Nano) together with > > a 10kHz clock-source and then count the number of external clock-ticks > > between 2 falling edges. > > > > - I used something like > > > https://www.botnroll.com/en/outros/4301-230vac-voltage-sensor-for-arduino.html > > to make the 230V into a 5V (DC) sine wave and connected that to D6 of > > the Arduino. D7 is connected to a voltage divider to get a 2.5V > > voltage reference (should be the zero-crossing voltage of the 230V > > input). > > > > - connected a PicDiv from Tom (a PD03) to an OXCO and the other end to > > pin D2 (ext interrupt) of the Arduino. > > > > +/- 2Hz (that's 80PPk right?) is way too much. So i'm curious if someone > > has a suggestion on how to improve this? > > > > > > > > Regards, > > > > > > Folkert van Heusden. > > > > p.s. the source code is at https://vanheusden.com/permshare/50hz.ino > > _______________________________________________ > > time-nuts mailing list -- time-nuts@lists.febo.com > > To unsubscribe send an email to time-nuts-leave@lists.febo.com > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe send an email to time-nuts-leave@lists.febo.com >

Hi, me too. I'm tracking ENTSO-e frequency, the western european grid. I sample the down-transformed voltage at 160ksamples/s, apply a high-Q digital bandpass filtering and fit a sine wave.  I do this for every single sine. The system is clocked with a 1E-8 TCXO. The resolution is 1E-4Hz. I store the results. There are some interesting patterns in the frequency. In the first quarter of the morning/afternoon hours there is a systematic rise/fall in frequency. This has to do with EEX ( European Energy Exchange) trading periods and over/underestimation of production/demand.  Maybe one could turn this knowledge into money, but unfortunately Im interested in the wrong thing (electronics) instead of the real important stuff (stock trading). Cheers Detlef Am 27.02.2023 um 20:23 schrieb folkert via time-nuts: > Hi, > > Has anyone experimented with measuring the net frequency? (50Hz in > Europe, 60Hz in the USA) > > Me and a friend are trying to do this as accurate and precise as > possible. His solution can do that with only a 0.0006Hz error, mine > sofar does +/- 2Hz. > Deviations of max. 0.150Hz are allowed (according to > https://www.mainsfrequency.com/ ) so 2Hz is useless. > > I tried the following: > > - use the hardware comparator of an AVR328 (Arduino Nano) together with > a 10kHz clock-source and then count the number of external clock-ticks > between 2 falling edges. > > - I used something like > https://www.botnroll.com/en/outros/4301-230vac-voltage-sensor-for-arduino.html > to make the 230V into a 5V (DC) sine wave and connected that to D6 of > the Arduino. D7 is connected to a voltage divider to get a 2.5V > voltage reference (should be the zero-crossing voltage of the 230V > input). > > - connected a PicDiv from Tom (a PD03) to an OXCO and the other end to > pin D2 (ext interrupt) of the Arduino. > > +/- 2Hz (that's 80PPk right?) is way too much. So i'm curious if someone > has a suggestion on how to improve this? > > > > Regards, > > > Folkert van Heusden. > > p.s. the source code is at https://vanheusden.com/permshare/50hz.ino > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe send an email to time-nuts-leave@lists.febo.com >

Hi Andy, there was a website, which showed the nine freq. error around the whole world in real time, did you see it ?and if yes where it is 73 KJ6UNH Alex On 2/28/2023 12:03 AM, Andy Talbot via time-nuts wrote: > I use the CCP module in a 16F628 PIC microcontroller. Measuring the time > for four cycles of the mains and then calculating its frequency. My > version gives a resolution of about 0.002Hz, but by changing the number of > cycles, clock frequency etc. this can be tweaked for even higher resolution > > In the UK the frequency variation is allowed to be an absolute maximum of > +/-0.5Hz, beyond which automatic load shedding kicks-in. This happened on > 9 August 2019 when two near-simultaneous failures occurred on the National > Grid. > https://www.ofgem.gov.uk/sites/default/files/docs/2019/09/eso_technical_report_-_final.pdf > > > Andy > www.g4jnt.com > > > > On Tue, 28 Feb 2023 at 05:14, Demetrios Matsakis via time-nuts < > time-nuts@lists.febo.com> wrote: > >> A few years ago I talked with Prof. Liu at Univ of Tennessee. She and her >> students had measurements all over the USA. Here is an interesting recent >> paper of hers: https://par.nsf.gov/servlets/purl/10234030, which has >> references to still other papers. Her bio at the end tells a little more >> about her activities. >> >>> On Feb 27, 2023, at 2:23 PM, folkert via time-nuts < >> time-nuts@lists.febo.com> wrote: >>> Hi, >>> >>> Has anyone experimented with measuring the net frequency? (50Hz in >>> Europe, 60Hz in the USA) >>> >>> Me and a friend are trying to do this as accurate and precise as >>> possible. His solution can do that with only a 0.0006Hz error, mine >>> sofar does +/- 2Hz. >>> Deviations of max. 0.150Hz are allowed (according to >>> https://www.mainsfrequency.com/ ) so 2Hz is useless. >>> >>> I tried the following: >>> >>> - use the hardware comparator of an AVR328 (Arduino Nano) together with >>> a 10kHz clock-source and then count the number of external clock-ticks >>> between 2 falling edges. >>> >>> - I used something like >>> >> https://www.botnroll.com/en/outros/4301-230vac-voltage-sensor-for-arduino.html >>> to make the 230V into a 5V (DC) sine wave and connected that to D6 of >>> the Arduino. D7 is connected to a voltage divider to get a 2.5V >>> voltage reference (should be the zero-crossing voltage of the 230V >>> input). >>> >>> - connected a PicDiv from Tom (a PD03) to an OXCO and the other end to >>> pin D2 (ext interrupt) of the Arduino. >>> >>> +/- 2Hz (that's 80PPk right?) is way too much. So i'm curious if someone >>> has a suggestion on how to improve this? >>> >>> >>> >>> Regards, >>> >>> >>> Folkert van Heusden. >>> >>> p.s. the source code is at https://vanheusden.com/permshare/50hz.ino >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts@lists.febo.com >>> To unsubscribe send an email to time-nuts-leave@lists.febo.com >> _______________________________________________ >> time-nuts mailing list -- time-nuts@lists.febo.com >> To unsubscribe send an email to time-nuts-leave@lists.febo.com >> > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe send an email to time-nuts-leave@lists.febo.com >

Alex, you may be looking for https://fnetpublic.utk.edu/index.html -- Sanjeev Gupta +65 98551208 http://www.linkedin.com/in/ghane On Thu, 2 Mar 2023 at 02:11, Alex Pummer via time-nuts < time-nuts@lists.febo.com> wrote: > Hi Andy, there was a website, which showed the nine freq. error around > the whole world in real time, did you see it ?and if yes where it is > 73 > KJ6UNH > Alex > > On 2/28/2023 12:03 AM, Andy Talbot via time-nuts wrote: > > I use the CCP module in a 16F628 PIC microcontroller. Measuring the > time > > for four cycles of the mains and then calculating its frequency. My > > version gives a resolution of about 0.002Hz, but by changing the number > of > > cycles, clock frequency etc. this can be tweaked for even higher > resolution > > > > In the UK the frequency variation is allowed to be an absolute maximum > of > > +/-0.5Hz, beyond which automatic load shedding kicks-in. This happened > on > > 9 August 2019 when two near-simultaneous failures occurred on the > National > > Grid. > > > https://www.ofgem.gov.uk/sites/default/files/docs/2019/09/eso_technical_report_-_final.pdf > > > > > > Andy > > www.g4jnt.com > > > > > > > > On Tue, 28 Feb 2023 at 05:14, Demetrios Matsakis via time-nuts < > > time-nuts@lists.febo.com> wrote: > > > >> A few years ago I talked with Prof. Liu at Univ of Tennessee. She and > her > >> students had measurements all over the USA. Here is an interesting > recent > >> paper of hers: https://par.nsf.gov/servlets/purl/10234030, which has > >> references to still other papers. Her bio at the end tells a little > more > >> about her activities. > >> > >>> On Feb 27, 2023, at 2:23 PM, folkert via time-nuts < > >> time-nuts@lists.febo.com> wrote: > >>> Hi, > >>> > >>> Has anyone experimented with measuring the net frequency? (50Hz in > >>> Europe, 60Hz in the USA) > >>> > >>> Me and a friend are trying to do this as accurate and precise as > >>> possible. His solution can do that with only a 0.0006Hz error, mine > >>> sofar does +/- 2Hz. > >>> Deviations of max. 0.150Hz are allowed (according to > >>> https://www.mainsfrequency.com/ ) so 2Hz is useless. > >>> > >>> I tried the following: > >>> > >>> - use the hardware comparator of an AVR328 (Arduino Nano) together with > >>> a 10kHz clock-source and then count the number of external > clock-ticks > >>> between 2 falling edges. > >>> > >>> - I used something like > >>> > >> > https://www.botnroll.com/en/outros/4301-230vac-voltage-sensor-for-arduino.html > >>> to make the 230V into a 5V (DC) sine wave and connected that to D6 of > >>> the Arduino. D7 is connected to a voltage divider to get a 2.5V > >>> voltage reference (should be the zero-crossing voltage of the 230V > >>> input). > >>> > >>> - connected a PicDiv from Tom (a PD03) to an OXCO and the other end to > >>> pin D2 (ext interrupt) of the Arduino. > >>> > >>> +/- 2Hz (that's 80PPk right?) is way too much. So i'm curious if > someone > >>> has a suggestion on how to improve this? > >>> > >>> > >>> > >>> Regards, > >>> > >>> > >>> Folkert van Heusden. > >>> > >>> p.s. the source code is at https://vanheusden.com/permshare/50hz.ino > >>> _______________________________________________ > >>> time-nuts mailing list -- time-nuts@lists.febo.com > >>> To unsubscribe send an email to time-nuts-leave@lists.febo.com > >> _______________________________________________ > >> time-nuts mailing list -- time-nuts@lists.febo.com > >> To unsubscribe send an email to time-nuts-leave@lists.febo.com > >> > > _______________________________________________ > > time-nuts mailing list -- time-nuts@lists.febo.com > > To unsubscribe send an email to time-nuts-leave@lists.febo.com > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe send an email to time-nuts-leave@lists.febo.com >

If you go to that web site, look at the Table Display, scroll down to Western Interconnection, and look for number 853. That particular Frequency Disturbance Recorder is in my home in Santa Rosa, California. Jeremy On Wed, Mar 1, 2023 at 5:51 PM Sanjeev Gupta via time-nuts < time-nuts@lists.febo.com> wrote: > Alex, you may be looking for https://fnetpublic.utk.edu/index.html > > -- > Sanjeev Gupta > +65 98551208 http://www.linkedin.com/in/ghane > > > On Thu, 2 Mar 2023 at 02:11, Alex Pummer via time-nuts < > time-nuts@lists.febo.com> wrote: > > > Hi Andy, there was a website, which showed the nine freq. error around > > the whole world in real time, did you see it ?and if yes where it is > > 73 > > KJ6UNH > > Alex > > > > On 2/28/2023 12:03 AM, Andy Talbot via time-nuts wrote: > > > I use the CCP module in a 16F628 PIC microcontroller. Measuring the > > time > > > for four cycles of the mains and then calculating its frequency. My > > > version gives a resolution of about 0.002Hz, but by changing the number > > of > > > cycles, clock frequency etc. this can be tweaked for even higher > > resolution > > > > > > In the UK the frequency variation is allowed to be an absolute maximum > > of > > > +/-0.5Hz, beyond which automatic load shedding kicks-in. This happened > > on > > > 9 August 2019 when two near-simultaneous failures occurred on the > > National > > > Grid. > > > > > > https://www.ofgem.gov.uk/sites/default/files/docs/2019/09/eso_technical_report_-_final.pdf > > > > > > > > > Andy > > > www.g4jnt.com > > > > > > > > > > > > On Tue, 28 Feb 2023 at 05:14, Demetrios Matsakis via time-nuts < > > > time-nuts@lists.febo.com> wrote: > > > > > >> A few years ago I talked with Prof. Liu at Univ of Tennessee. She and > > her > > >> students had measurements all over the USA. Here is an interesting > > recent > > >> paper of hers: https://par.nsf.gov/servlets/purl/10234030, which has > > >> references to still other papers. Her bio at the end tells a little > > more > > >> about her activities. > > >> > > >>> On Feb 27, 2023, at 2:23 PM, folkert via time-nuts < > > >> time-nuts@lists.febo.com> wrote: > > >>> Hi, > > >>> > > >>> Has anyone experimented with measuring the net frequency? (50Hz in > > >>> Europe, 60Hz in the USA) > > >>> > > >>> Me and a friend are trying to do this as accurate and precise as > > >>> possible. His solution can do that with only a 0.0006Hz error, mine > > >>> sofar does +/- 2Hz. > > >>> Deviations of max. 0.150Hz are allowed (according to > > >>> https://www.mainsfrequency.com/ ) so 2Hz is useless. > > >>> > > >>> I tried the following: > > >>> > > >>> - use the hardware comparator of an AVR328 (Arduino Nano) together > with > > >>> a 10kHz clock-source and then count the number of external > > clock-ticks > > >>> between 2 falling edges. > > >>> > > >>> - I used something like > > >>> > > >> > > > https://www.botnroll.com/en/outros/4301-230vac-voltage-sensor-for-arduino.html > > >>> to make the 230V into a 5V (DC) sine wave and connected that to D6 > of > > >>> the Arduino. D7 is connected to a voltage divider to get a 2.5V > > >>> voltage reference (should be the zero-crossing voltage of the 230V > > >>> input). > > >>> > > >>> - connected a PicDiv from Tom (a PD03) to an OXCO and the other end > to > > >>> pin D2 (ext interrupt) of the Arduino. > > >>> > > >>> +/- 2Hz (that's 80PPk right?) is way too much. So i'm curious if > > someone > > >>> has a suggestion on how to improve this? > > >>> > > >>> > > >>> > > >>> Regards, > > >>> > > >>> > > >>> Folkert van Heusden. > > >>> > > >>> p.s. the source code is at https://vanheusden.com/permshare/50hz.ino > > >>> _______________________________________________ > > >>> time-nuts mailing list -- time-nuts@lists.febo.com > > >>> To unsubscribe send an email to time-nuts-leave@lists.febo.com > > >> _______________________________________________ > > >> time-nuts mailing list -- time-nuts@lists.febo.com > > >> To unsubscribe send an email to time-nuts-leave@lists.febo.com > > >> > > > _______________________________________________ > > > time-nuts mailing list -- time-nuts@lists.febo.com > > > To unsubscribe send an email to time-nuts-leave@lists.febo.com > > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts@lists.febo.com > > To unsubscribe send an email to time-nuts-leave@lists.febo.com > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe send an email to time-nuts-leave@lists.febo.com > -- Jeremy Nichols Sent from my iPad 6.