I noticed following information (source: http://www.mainsfrequency.com/news.htm#2015_1): Minimum and maximum mains frequency To clarify the question "how stable is the mains frequency", data of the last 13 months was analyzed (July 2011 to July 2012). The greatest fluctuations occurred regularly on the hour change, which is caused by the use of products of hours. The limits of frequency range allowed in normal operation (49.8 Hz to 50.2 Hz) were never reached or exceeded in this period: * Maximum frequency: 50,164 Hz on tuesday, 13.12.2011, 23:52:54 * Minimum frequency: 49,849 Hz on tuesday, 17.01.2012, 23:02:08 Then I was curious if "leap second" event could be noticed on the main frequency charts. May be its is no correlation at all. Regards, Vlad On 2017-01-03 12:01, J wrote: > Power utilities tweak the system frequency on a daily basis to keep > MAINS powered clocks correct. I wonder what their correction strategy > was for the leap second? > > On Tue, Jan 3, 2017 at 11:05 AM, Vlad <time@patoka.org> wrote: > >> Speaking about MAIN... I was interesting to see if "leap second" >> event has correlation with MAIN frequency fluctuation >> >> Here is graphs for the MAIN periods recorded. Note: The data on the >> charts is "smoothed" by Bezier curves >> >> I could see some "surge" which starts to climb in December 30 and >> end at Dec 31 at the time close to the "leap second" event. But not >> sharp. >> >> For 16-12-29 00:00 to 17-01-02 00:00 >> http://www.patoka.ca/OCXO/60hz-periods-Dec29-Jan2.png [1] >> >> For Dec 31: >> http://www.patoka.ca/OCXO/60hz-periods-Dec31.png [2] >> >> It will be interesting to see/compare if anybody else has similar >> stats. >> >> Regards, >> Vlad >> >> On 2017-01-02 13:00, Tim Shoppa wrote: >> What modern loads are actually sensitive to high (say, +10 to +20%) >> line >> voltage? >> >> Old incandescent light bulbs were among the most sensitive loads in >> the >> past (so much so, that 130V light bulbs were commonly available from >> the >> industrial suppliers). >> >> I would naively expect the modern CFL's and LED replacements to be >> fine >> with higher line voltage because they have their own built-in >> switching >> regulation. >> >> A lot of modern electronic equipment with switching supplies, are >> just fine >> at +20% line voltage and may even run cooler. >> >> Tim N3QE >> >> On Sun, Jan 1, 2017 at 11:49 PM, Bill Byrom <time@radio.sent.com> >> wrote: >> >> There are a couple of recent threads concerning the power line >> mains >> voltage standards. After a bit of research and thinking, I have >> found >> that this is a complex topic. The simple answer is: >> >> * The standard in the US for the past 50 years has been 120/240 V >> +/- 5% >> RMS at the service entrance to the building. This is a range of >> 114/228 V to 126/252 V. >> * The load voltage could be as low as 110/220 V and as high as >> 125/250 V >> and be within specifications. >> >> There are two voltage measurement points to consider: >> >> (1) Service voltage: This is the RMS voltage measured at the service >> entrance to the building (at the metering point). >> (2) Utilization voltage: This is the RMS voltage measured at the >> load. >> It might be measured at an unused socket in a power strip >> feeding >> several pieces of electronic equipment, for example. There are >> of >> course many different utilization voltages present in a home or >> business, depending on where you make the measurement. >> >> Most US homes and small businesses are powered by what is commonly >> called a "split-phase" 240 V feed. The final distribution system >> transformer has a 240 V center-tapped secondary. The center tap is >> grounded, and three wires are fed to the building (actually it might >> be >> up to around 6 houses): >> (1) Leg L1 or phase A (red wire) -- This wire will measure 120 V to >> the >> neutral or 240 V to Leg L2. >> (2) Neutral (white wire) -- This wire is grounded at the >> distribution >> system and at the service entrance to the building. >> (3) Leg L2 phase B (black wire) -- This wire will measure 120 V to >> the >> neutral or 240 V to Leg L1. >> >> Large appliances and HVAC systems are usually connected across L1-L2 >> (240 V), while most sockets are on circuits either connected across >> L1- >> neutral (120 V) or L2-neutral (120 V). >> >> The voltages I have described are the current standardized values >> for >> the service voltage which have been in general use for about 50 >> years >> (120/240 V +/- 5%). I believe that the original systems installed >> before >> 1940 were designed for a 110/220 V nominal service voltage, but >> after a >> report in 1949 the nominal service voltage was increased to 117/234 >> V, >> as specified in ANSI C84.1-1954. After research in actual buildings, >> in >> the 1960's the nominal service voltage was increased again, to >> 120/240 V >> in the ANSI C84.1-1970 standard. The purpose is to keep the >> utilization >> voltage at the load above 110/220 V. >> >> The voltage at the service entrance should in most cases be in Range >> A >> (120/240V +/-5%). On each 120V leg the service voltage should >> therefore >> be between 114 and 126 V. The utilization voltage at the load should >> be >> between 110 and 125 V due to losses in building wiring. >> >> See details of the current specifications at: >> >> http://www.pge.com/includes/docs/pdfs/mybusiness/ [3] >> customerservice/energystatus/powerquality/voltage_tolerance.pdf >> >> These voltage specifications were designed for resistive loads and >> measurement of the true RMS voltage. In most electronic equipment >> built >> over the past 50 years, the power supply input circuitry is >> basically a >> rectifier connected to a smoothing capacitor. This leads to high >> input >> current surges during the peaks of the waveform, so that the peak >> voltage is reduced much more by the building wiring resistance than >> if >> the load was resistive for the same power consumption. >> >> So the waveform shape at different utilization locations in a >> building >> (with active equipment loads) may be different, so the voltage >> measured >> by different AC measuring instruments can differ. Many meters are >> full >> wave average measuring but calibrated so they only read RMS voltage >> correctly on pure sinewaves. Other meters are true RMS measuring and >> will read very close the correct RMS voltage even if the waveform is >> distorted. >> -- >> >> Bill Byrom N5BB >> >> On Sun, Jan 1, 2017, at 12:16 PM, CIW308 VE6OH wrote: >> >>> Mark, >> >>> >> >>> CSA have standards for over and under voltage, Typical no more >> that 3% >>> over and 5% under if memory serves me. >> >>> >> >>> This might help ( >> >>> http://www.safetyauthority.ca/sites/default/files/csa- [4] >> fia3660-voltagedropcalc.pdf >>> ) >> >>> The power companies here in Alberta are generally good about >> fixing >> >>> problems with line regulation. >> >>> There can be problems with industrial areas and big welders or >> motors >>> staring as I am sure you know. >> >>> I am sure they do not want the bill for replacing equipment that >> was >> >>> subjected to over voltage. >> >>> >> >>> On UPSs: I am sure you are aware that may of them are not TRUE >>> sine wave >>> so the DMM may not read correctly. >> >>> >> >>> Mitch >> >> _______________________________________________ >> 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. >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts [5] >> and follow the instructions there. > > -- > WBW, > > V.P. > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts [5] > and follow the instructions there. > > > > Links: > ------ > [1] http://www.patoka.ca/OCXO/60hz-periods-Dec29-Jan2.png > [2] http://www.patoka.ca/OCXO/60hz-periods-Dec31.png > [3] http://www.pge.com/includes/docs/pdfs/mybusiness/ > [4] http://www.safetyauthority.ca/sites/default/files/csa- > [5] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts -- WBW, V.P.

I once had some odd equipment failures which we found out were caused by the line voltage being at 142V. This was in the mid 80's in Costa Mesa CA. The tech they sent out told me they had us on the wrong transformer tap. Lowest I've seen was 70V in Hawaii, with everyone coming home about 5PM and switching on air conditioners. We had to run our TV on a variac and adjust the voltage to keep the picture from shrinking. Since those days, that's the numbers I design equipment to, if it is to run from 115V supplies. That rule has never let me down.

Did the utility replace the damaged equipment? On Tue, Jan 3, 2017 at 9:33 PM Van Horn, David < david.vanhorn@backcountryaccess.com> wrote: > I once had some odd equipment failures which we found out were caused by > the line voltage being at 142V. > > This was in the mid 80's in Costa Mesa CA. The tech they sent out told me > they had us on the wrong transformer tap. > > > > Lowest I've seen was 70V in Hawaii, with everyone coming home about 5PM > and switching on air conditioners. We had to run our TV on a variac and > adjust the voltage to keep the picture from shrinking. > > > > Since those days, that's the numbers I design equipment to, if it is to > run from 115V supplies. That rule has never let me down. > > _______________________________________________ > > 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. > > -- Sent from Gmail Mobile

HAHAHAHAHAHA..... No, -----Original Message----- From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Jeremy Nichols Sent: Tuesday, January 3, 2017 11:48 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Line Voltage - USA Did the utility replace the damaged equipment? On Tue, Jan 3, 2017 at 9:33 PM Van Horn, David < david.vanhorn@backcountryaccess.com> wrote: > I once had some odd equipment failures which we found out were caused > by the line voltage being at 142V. > > This was in the mid 80's in Costa Mesa CA. The tech they sent out > told me they had us on the wrong transformer tap. > > > > Lowest I've seen was 70V in Hawaii, with everyone coming home about > 5PM and switching on air conditioners. We had to run our TV on a > variac and adjust the voltage to keep the picture from shrinking. > > > > Since those days, that's the numbers I design equipment to, if it is > to run from 115V supplies. That rule has never let me down. > > _______________________________________________ > > 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. > > -- Sent from Gmail Mobile _______________________________________________ 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.