Re: Power line timing -- setting a clock
Thank you, Walt, for reporting the time-inaccuracy of mains-synched
clocks that I see. I'm glad you are far distant from me, and so you have
data from a new location and generation utility.
I last set all my appliance and mains-synched clocks late on March 9, to
advance the time for DST. I just checked and all the mains-synched
clocks roll the minute digit simultaneously and all are now about 24
seconds fast of GPS time after about two weeks. Historically here, the
mains clocks being fast is unusual; it is more common for them to run
slow. But, a 24 second error is not unusual.
I'm in Southern California and Walt is in Washington, also on the west
coast but not near me. So, this mains frequency effect on old clocks is
not local to my independent-utility city.
Please folks, stop quoting specs that may or may not still be valid and
may or may not be complied with by electric generation utilities.
Instead, let's get data!
I have long set all my appliance clocks to the second, even though they
don't display seconds. The final button-push in the time-setting command
will start the clock time at the zero second. Try it! Use a
known-accurate (e.g. GPS) clock and set your appliance clocks, then
check them again in a few days or more against your accurate clock.
Report the results and your location. That's data!
I bought one of the new-Heathkit LED clock kits a few years ago; this
new design is a mains-synched clock. I have never built that kit but I
was disappointed to hear user complaints that it did not keep accurate
time. In fact, though, those that were assembled may just have been
showing the same mains-frequency issue we are discussing.
There are some cell phone apps that will read the phone's GPS and show
time to the second. I use "Sol Et Umbra" (it's a sundial application)
and "Atomic Time," which shows a sweeping second hand; both are free and
Android apps.
I recommend the Geppetto GPS Clock offered on Tindie; its red LED
display (including tenth seconds) closely resembles that of the old
Heathkit GC-1000 clock; the latest versions access multi-GNSS signals.
Best wishes,
Larry McDavid W6FUB
Anaheim, California (SE of Los Angeles, near Disneyland)
On 3/25/2024 1:59 PM, Walt wrote:
You are not alone. I was intrigued by this thread, so I plugged in my Heathkit GC-1005 mains-powered digital clock and set the time against my PST-1030 WWV Time Clock.
I went outside to do some chores, and when I came back in 3 1/2 hours later, I'll be darned if the clock was not 3.5 seconds ahead already! Now it's been almost 4 hours and the Heath is almost 4 seconds ahead.
...
Here in the UK we have a grid that is not synchronised to Europe which for
many years has kept to within +/- 20 seconds or so of UTC according to
my casual monitoring. However, in the last decade, I've noticed the timing
excursions getting larger, perhaps to as much as -50s before it corrects
over the next few days. I almost certainly do not have the zero reference
correct, but I've definitely seen as much as one minute deviation overall
in a space of a few days to a week.
I have a continuous real time display of frequency and time discrepancy,
but it doesn't have logging - something I always intend to do but never get
a round tuit. It's bit of an empirical observation, but I've noticed the
wider swings in timing are when the weather is windy, and even more so,
windy and sunny in summer when power generation (as reported by
https://www.gridwatch.templar.co.uk/ ) has more than 50% coming from wind
and solar.
This makes sense as those two sources have no ability to control frequency
- they just generate at whatever frequency the Grid happens to be at. In
cold, windless dark conditions gas and nuclear provide the bulk of energy
and those are the ones National Grid have complete control over, so can
maintain timing more closely.
I can't help wondering if solar and wind inverters could be designed to
push energy into the grid with leading or lagging power factor. The
ability to set PF from Nat-Grid central control would give them the same
advantage as being able to speed up or slow down the gas / nuclear
generation. There is a huge base of wind generation already on place, and
this is being extended so it may be too late to ask for retrofitting, but
the inability to control frequency can lead to catastrophic instability and
cascade of minor faults - as witnessed in August 2019 when 10% of the UK
supplies automatically shut down to maintain a rapidly dropping frequency
caused by two simultaneous failures. It was short lived before N-Grid
could correct things within tens of minutes, but still a "major failure".
https://assets.publishing.service.gov.uk/media/5d96100340f0b61743bd4cc3/20191003_E3C_Interim_Report_into_GB_Power_Disruption.pdf
There are manuy other reports on it worth a read.
It was August with solar and wind generation up. It was certainly windy
over that period as I was at a festival where tents were wildly flapping
and getting blown away. I suspect over 60% of the generation at the time
was wind. The festival was all powered by local generators, so I would
never have noticed any grid power outage other than total internet failure
for a while that afternoon.
Andy
www.g4jnt.com
On Tue, 26 Mar 2024 at 08:13, Larry McDavid via time-nuts <
time-nuts@lists.febo.com> wrote:
Thank you, Walt, for reporting the time-inaccuracy of mains-synched
clocks that I see. I'm glad you are far distant from me, and so you have
data from a new location and generation utility.
I last set all my appliance and mains-synched clocks late on March 9, to
advance the time for DST. I just checked and all the mains-synched
clocks roll the minute digit simultaneously and all are now about 24
seconds fast of GPS time after about two weeks. Historically here, the
mains clocks being fast is unusual; it is more common for them to run
slow. But, a 24 second error is not unusual.
I'm in Southern California and Walt is in Washington, also on the west
coast but not near me. So, this mains frequency effect on old clocks is
not local to my independent-utility city.
Please folks, stop quoting specs that may or may not still be valid and
may or may not be complied with by electric generation utilities.
Instead, let's get data!
I have long set all my appliance clocks to the second, even though they
don't display seconds. The final button-push in the time-setting command
will start the clock time at the zero second. Try it! Use a
known-accurate (e.g. GPS) clock and set your appliance clocks, then
check them again in a few days or more against your accurate clock.
Report the results and your location. That's data!
I bought one of the new-Heathkit LED clock kits a few years ago; this
new design is a mains-synched clock. I have never built that kit but I
was disappointed to hear user complaints that it did not keep accurate
time. In fact, though, those that were assembled may just have been
showing the same mains-frequency issue we are discussing.
There are some cell phone apps that will read the phone's GPS and show
time to the second. I use "Sol Et Umbra" (it's a sundial application)
and "Atomic Time," which shows a sweeping second hand; both are free and
Android apps.
I recommend the Geppetto GPS Clock offered on Tindie; its red LED
display (including tenth seconds) closely resembles that of the old
Heathkit GC-1000 clock; the latest versions access multi-GNSS signals.
Best wishes,
Larry McDavid W6FUB
Anaheim, California (SE of Los Angeles, near Disneyland)
On 3/25/2024 1:59 PM, Walt wrote:
You are not alone. I was intrigued by this thread, so I plugged in my
Heathkit GC-1005 mains-powered digital clock and set the time against my
PST-1030 WWV Time Clock.
I went outside to do some chores, and when I came back in 3 1/2 hours
later, I'll be darned if the clock was not 3.5 seconds ahead already! Now
it's been almost 4 hours and the Heath is almost 4 seconds ahead.
...
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe send an email to time-nuts-leave@lists.febo.com
I've been logging the uk grid for some time now. Here's one if the more
interesting graphs...
Tony Flavin
On Tue, 26 Mar 2024, 10:43 Andy Talbot via time-nuts, <
time-nuts@lists.febo.com> wrote:
Here in the UK we have a grid that is not synchronised to Europe which for
many years has kept to within +/- 20 seconds or so of UTC according to
my casual monitoring. However, in the last decade, I've noticed the timing
excursions getting larger, perhaps to as much as -50s before it corrects
over the next few days. I almost certainly do not have the zero reference
correct, but I've definitely seen as much as one minute deviation overall
in a space of a few days to a week.
I have a continuous real time display of frequency and time discrepancy,
but it doesn't have logging - something I always intend to do but never get
a round tuit. It's bit of an empirical observation, but I've noticed the
wider swings in timing are when the weather is windy, and even more so,
windy and sunny in summer when power generation (as reported by
https://www.gridwatch.templar.co.uk/ ) has more than 50% coming from wind
and solar.
This makes sense as those two sources have no ability to control frequency
- they just generate at whatever frequency the Grid happens to be at. In
cold, windless dark conditions gas and nuclear provide the bulk of energy
and those are the ones National Grid have complete control over, so can
maintain timing more closely.
I can't help wondering if solar and wind inverters could be designed to
push energy into the grid with leading or lagging power factor. The
ability to set PF from Nat-Grid central control would give them the same
advantage as being able to speed up or slow down the gas / nuclear
generation. There is a huge base of wind generation already on place, and
this is being extended so it may be too late to ask for retrofitting, but
the inability to control frequency can lead to catastrophic instability and
cascade of minor faults - as witnessed in August 2019 when 10% of the UK
supplies automatically shut down to maintain a rapidly dropping frequency
caused by two simultaneous failures. It was short lived before N-Grid
could correct things within tens of minutes, but still a "major failure".
There are manuy other reports on it worth a read.
It was August with solar and wind generation up. It was certainly windy
over that period as I was at a festival where tents were wildly flapping
and getting blown away. I suspect over 60% of the generation at the time
was wind. The festival was all powered by local generators, so I would
never have noticed any grid power outage other than total internet failure
for a while that afternoon.
Andy
www.g4jnt.com
On Tue, 26 Mar 2024 at 08:13, Larry McDavid via time-nuts <
time-nuts@lists.febo.com> wrote:
Thank you, Walt, for reporting the time-inaccuracy of mains-synched
clocks that I see. I'm glad you are far distant from me, and so you have
data from a new location and generation utility.
I last set all my appliance and mains-synched clocks late on March 9, to
advance the time for DST. I just checked and all the mains-synched
clocks roll the minute digit simultaneously and all are now about 24
seconds fast of GPS time after about two weeks. Historically here, the
mains clocks being fast is unusual; it is more common for them to run
slow. But, a 24 second error is not unusual.
I'm in Southern California and Walt is in Washington, also on the west
coast but not near me. So, this mains frequency effect on old clocks is
not local to my independent-utility city.
Please folks, stop quoting specs that may or may not still be valid and
may or may not be complied with by electric generation utilities.
Instead, let's get data!
I have long set all my appliance clocks to the second, even though they
don't display seconds. The final button-push in the time-setting command
will start the clock time at the zero second. Try it! Use a
known-accurate (e.g. GPS) clock and set your appliance clocks, then
check them again in a few days or more against your accurate clock.
Report the results and your location. That's data!
I bought one of the new-Heathkit LED clock kits a few years ago; this
new design is a mains-synched clock. I have never built that kit but I
was disappointed to hear user complaints that it did not keep accurate
time. In fact, though, those that were assembled may just have been
showing the same mains-frequency issue we are discussing.
There are some cell phone apps that will read the phone's GPS and show
time to the second. I use "Sol Et Umbra" (it's a sundial application)
and "Atomic Time," which shows a sweeping second hand; both are free and
Android apps.
I recommend the Geppetto GPS Clock offered on Tindie; its red LED
display (including tenth seconds) closely resembles that of the old
Heathkit GC-1000 clock; the latest versions access multi-GNSS signals.
Best wishes,
Larry McDavid W6FUB
Anaheim, California (SE of Los Angeles, near Disneyland)
On 3/25/2024 1:59 PM, Walt wrote:
You are not alone. I was intrigued by this thread, so I plugged in my
Heathkit GC-1005 mains-powered digital clock and set the time against my
PST-1030 WWV Time Clock.
I went outside to do some chores, and when I came back in 3 1/2 hours
later, I'll be darned if the clock was not 3.5 seconds ahead already!
Now
it's been almost 4 hours and the Heath is almost 4 seconds ahead.
...
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
Andy Talbot via time-nuts writes:
I can't help wondering if solar and wind inverters could be designed to
push energy into the grid with leading or lagging power factor.
They can, and for non-consumer-size installations it is already a
requirement pretty much everywhere, although the specific parameters
differ a lot from grid to grid.
Now that battery prices have come down, there are people on the grid-side
arguing for even tougher parameters, such that new installations will be forced to install "at least a couple of minutes worth of batteries"
The big issue is regulation and control.
Once they are electro-magneto-mechanically coupled together via the
grid, big rotating iron cylinders will Do The Right Thing because
the Laws of Physics controls them, and you can concentrate on getting
the power balance right.
Once your power sources are tens of thousands of computers, each
controlling an inverter from some unsynchronized source of power,
it becomes a really, /really/ challenging control & regulation
issue.
Some people have argued for taking the easy way out: Simply lock the
grid to UTC, so that everybody can have a local "GPS reference" and know
if phase is leading or lagging.
Problem is, as nice as it sounds, it doesn't work: Both distances
and transformers mean that there are intrinsic phase differences
and what's worse, they deepend on the amount and very much on the
direction of the energy flow through the transformers.
The other easy solution is to make the "backbone" HVDC, which not
only makes the cables (air or ground) improve rather than cause
stability with their capacitance, but also reduces the control
problem to simply one of voltage.
That is probably where we end up eventually, but as of yet, the
cost is still prohibitive, and the idea of having three or more
HVDC lines meet on a big bolt&nut connection, where you have no way
to steer the power flow, makes a lot of people uncomfortable. With
HVAC you can at least steer the flow somewhat by adjusting the
voltage with the winding-selectors on the transformators.
So right now, everybody are implementing "intelligent algorithms"
in the inverters, and yes, some call it "AI". As of yet we have
little idea, and even less confidence, that it will Do The Right Thing
when parameters jump through their windows, so everybody is
looking forward to the next grid collapse, and hoping it happens
to a grid somewhat like, but not exactly their own.
One other huge difference between big rotating lumps of iron is
how much abuse they and their copper-windings can endure, compared
to high voltage semiconductors which are uncomfortably sensitive.
That's why some grids are taking no chances and installing "increased
momentum" in their grid, in the shape of big lumps of rotating iron,
configured as flywheels with a single motor/generator.
--
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
phk@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.
The March/April issue of IEEE Power and Engineering Magazine discusses just such issues with "Inverter Based Resources"
It's been a continuing topic over the last couple years in PES magazine - the whole thing of managing distributed generation and storage is really, really complex.
Don't know if it is behind the IEEE Paywall, but here's the table of contents
https://ieeexplore.ieee.org/xpl/tocresult.jsp?isnumber=10444650&punumber=8014
On Tue, 26 Mar 2024 13:20:12 +0000, Poul-Henning Kamp via time-nuts time-nuts@lists.febo.com wrote:
Andy Talbot via time-nuts writes:
I can't help wondering if solar and wind inverters could be designed to
push energy into the grid with leading or lagging power factor.
They can, and for non-consumer-size installations it is already a
requirement pretty much everywhere, although the specific parameters
differ a lot from grid to grid.
Now that battery prices have come down, there are people on the grid-side
arguing for even tougher parameters, such that new installations will be forced to install "at least a couple of minutes worth of batteries"
The big issue is regulation and control.
Once they are electro-magneto-mechanically coupled together via the
grid, big rotating iron cylinders will Do The Right Thing because
the Laws of Physics controls them, and you can concentrate on getting
the power balance right.
Once your power sources are tens of thousands of computers, each
controlling an inverter from some unsynchronized source of power,
it becomes a really, /really/ challenging control & regulation
issue.
Some people have argued for taking the easy way out: Simply lock the
grid to UTC, so that everybody can have a local "GPS reference" and know
if phase is leading or lagging.
Problem is, as nice as it sounds, it doesn't work: Both distances
and transformers mean that there are intrinsic phase differences
and what's worse, they deepend on the amount and very much on the
direction of the energy flow through the transformers.
The other easy solution is to make the "backbone" HVDC, which not
only makes the cables (air or ground) improve rather than cause
stability with their capacitance, but also reduces the control
problem to simply one of voltage.
That is probably where we end up eventually, but as of yet, the
cost is still prohibitive, and the idea of having three or more
HVDC lines meet on a big bolt&nut connection, where you have no way
to steer the power flow, makes a lot of people uncomfortable. With
HVAC you can at least steer the flow somewhat by adjusting the
voltage with the winding-selectors on the transformators.
So right now, everybody are implementing "intelligent algorithms"
in the inverters, and yes, some call it "AI". As of yet we have
little idea, and even less confidence, that it will Do The Right Thing
when parameters jump through their windows, so everybody is
looking forward to the next grid collapse, and hoping it happens
to a grid somewhat like, but not exactly their own.
One other huge difference between big rotating lumps of iron is
how much abuse they and their copper-windings can endure, compared
to high voltage semiconductors which are uncomfortably sensitive.
That's why some grids are taking no chances and installing "increased
momentum" in their grid, in the shape of big lumps of rotating iron,
configured as flywheels with a single motor/generator.
--
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
phk@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.
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe send an email to time-nuts-leave@lists.febo.com
Good morning, Larry,
Just wanted to let you know that I observed my line-controlled clock being
17 seconds behind this morning. A quick glance at
https://fnetpublic.utk.edu/frequencymap.html showed that the WECC frequency
was hovering around 59.95 at the time. Since this website doesn't offer
historical data, who knows what the trend could have been in the last 9
hours since I last happened to look at my clocks.
I'm not yet set up to record the line frequency here - too many other
projects on the table. But I do watch the delta between my Heath and GPS
time, and since you first brought up the issue, it's usually been within a
few seconds. This morning's event is quite unusual.
Cheers,
Walt
I've been logging the uk grid for some time now. Here's one if the more interesting graphs...
Tony Flavin
On Tue, 26 Mar 2024, 10:43 Andy Talbot via time-nuts, <time-nuts@lists.febo.com mailto:time-nuts@lists.febo.com > wrote:
Here in the UK we have a grid that is not synchronised to Europe which for
many years has kept to within +/- 20 seconds or so of UTC according to
my casual monitoring. However, in the last decade, I've noticed the timing
excursions getting larger, perhaps to as much as -50s before it corrects
over the next few days. I almost certainly do not have the zero reference
correct, but I've definitely seen as much as one minute deviation overall
in a space of a few days to a week.
I have a continuous real time display of frequency and time discrepancy,
but it doesn't have logging - something I always intend to do but never get
a round tuit. It's bit of an empirical observation, but I've noticed the
wider swings in timing are when the weather is windy, and even more so,
windy and sunny in summer when power generation (as reported by
https://www.gridwatch.templar.co.uk/ ) has more than 50% coming from wind
and solar.
This makes sense as those two sources have no ability to control frequency
- they just generate at whatever frequency the Grid happens to be at. In
cold, windless dark conditions gas and nuclear provide the bulk of energy
and those are the ones National Grid have complete control over, so can
maintain timing more closely.
I can't help wondering if solar and wind inverters could be designed to
push energy into the grid with leading or lagging power factor. The
ability to set PF from Nat-Grid central control would give them the same
advantage as being able to speed up or slow down the gas / nuclear
generation. There is a huge base of wind generation already on place, and
this is being extended so it may be too late to ask for retrofitting, but
the inability to control frequency can lead to catastrophic instability and
cascade of minor faults - as witnessed in August 2019 when 10% of the UK
supplies automatically shut down to maintain a rapidly dropping frequency
caused by two simultaneous failures. It was short lived before N-Grid
could correct things within tens of minutes, but still a "major failure".
https://assets.publishing.service.gov.uk/media/5d96100340f0b61743bd4cc3/20191003_E3C_Interim_Report_into_GB_Power_Disruption.pdf
There are manuy other reports on it worth a read.
It was August with solar and wind generation up. It was certainly windy
over that period as I was at a festival where tents were wildly flapping
and getting blown away. I suspect over 60% of the generation at the time
was wind. The festival was all powered by local generators, so I would
never have noticed any grid power outage other than total internet failure
for a while that afternoon.
Andy
www.g4jnt.com http://www.g4jnt.com
On Tue, 26 Mar 2024 at 08:13, Larry McDavid via time-nuts <
time-nuts@lists.febo.com mailto:time-nuts@lists.febo.com > wrote:
Thank you, Walt, for reporting the time-inaccuracy of mains-synched
clocks that I see. I'm glad you are far distant from me, and so you have
data from a new location and generation utility.
I last set all my appliance and mains-synched clocks late on March 9, to
advance the time for DST. I just checked and all the mains-synched
clocks roll the minute digit simultaneously and all are now about 24
seconds fast of GPS time after about two weeks. Historically here, the
mains clocks being fast is unusual; it is more common for them to run
slow. But, a 24 second error is not unusual.
I'm in Southern California and Walt is in Washington, also on the west
coast but not near me. So, this mains frequency effect on old clocks is
not local to my independent-utility city.
Please folks, stop quoting specs that may or may not still be valid and
may or may not be complied with by electric generation utilities.
Instead, let's get data!
I have long set all my appliance clocks to the second, even though they
don't display seconds. The final button-push in the time-setting command
will start the clock time at the zero second. Try it! Use a
known-accurate (e.g. GPS) clock and set your appliance clocks, then
check them again in a few days or more against your accurate clock.
Report the results and your location. That's data!
I bought one of the new-Heathkit LED clock kits a few years ago; this
new design is a mains-synched clock. I have never built that kit but I
was disappointed to hear user complaints that it did not keep accurate
time. In fact, though, those that were assembled may just have been
showing the same mains-frequency issue we are discussing.
There are some cell phone apps that will read the phone's GPS and show
time to the second. I use "Sol Et Umbra" (it's a sundial application)
and "Atomic Time," which shows a sweeping second hand; both are free and
Android apps.
I recommend the Geppetto GPS Clock offered on Tindie; its red LED
display (including tenth seconds) closely resembles that of the old
Heathkit GC-1000 clock; the latest versions access multi-GNSS signals.
Best wishes,
Larry McDavid W6FUB
Anaheim, California (SE of Los Angeles, near Disneyland)
On 3/25/2024 1:59 PM, Walt wrote:
You are not alone. I was intrigued by this thread, so I plugged in my
Heathkit GC-1005 mains-powered digital clock and set the time against my
PST-1030 WWV Time Clock.
I went outside to do some chores, and when I came back in 3 1/2 hours
later, I'll be darned if the clock was not 3.5 seconds ahead already! Now
it's been almost 4 hours and the Heath is almost 4 seconds ahead.
...
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To unsubscribe send an email to time-nuts-leave@lists.febo.com mailto:time-nuts-leave@lists.febo.com
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Have you tried to investigate why there is a "notch" exactly where it is
less expected?
On Sat, Apr 13, 2024 at 1:34 PM Tony Flavin via time-nuts <
time-nuts@lists.febo.com> wrote:
I've been logging the uk grid for some time now. Here's one if the more
interesting graphs...
Tony Flavin
On Tue, 26 Mar 2024, 10:43 Andy Talbot via time-nuts, <
time-nuts@lists.febo.com mailto:time-nuts@lists.febo.com > wrote:
Here in the UK we have a grid that is not synchronised to Europe which for
many years has kept to within +/- 20 seconds or so of UTC according to
my casual monitoring. However, in the last decade, I've noticed the timing
excursions getting larger, perhaps to as much as -50s before it corrects
over the next few days. I almost certainly do not have the zero reference
correct, but I've definitely seen as much as one minute deviation overall
in a space of a few days to a week.
I have a continuous real time display of frequency and time discrepancy,
but it doesn't have logging - something I always intend to do but never get
a round tuit. It's bit of an empirical observation, but I've noticed the
wider swings in timing are when the weather is windy, and even more so,
windy and sunny in summer when power generation (as reported by
https://www.gridwatch.templar.co.uk/ ) has more than 50% coming from wind
and solar.
This makes sense as those two sources have no ability to control frequency
- they just generate at whatever frequency the Grid happens to be at. In
cold, windless dark conditions gas and nuclear provide the bulk of energy
and those are the ones National Grid have complete control over, so can
maintain timing more closely.
I can't help wondering if solar and wind inverters could be designed to
push energy into the grid with leading or lagging power factor. The
ability to set PF from Nat-Grid central control would give them the same
advantage as being able to speed up or slow down the gas / nuclear
generation. There is a huge base of wind generation already on place, and
this is being extended so it may be too late to ask for retrofitting, but
the inability to control frequency can lead to catastrophic instability and
cascade of minor faults - as witnessed in August 2019 when 10% of the UK
supplies automatically shut down to maintain a rapidly dropping frequency
caused by two simultaneous failures. It was short lived before N-Grid
could correct things within tens of minutes, but still a "major failure".
There are manuy other reports on it worth a read.
It was August with solar and wind generation up. It was certainly windy
over that period as I was at a festival where tents were wildly flapping
and getting blown away. I suspect over 60% of the generation at the time
was wind. The festival was all powered by local generators, so I would
never have noticed any grid power outage other than total internet failure
for a while that afternoon.
Andy
www.g4jnt.com http://www.g4jnt.com
On Tue, 26 Mar 2024 at 08:13, Larry McDavid via time-nuts <
time-nuts@lists.febo.com mailto:time-nuts@lists.febo.com > wrote:
Thank you, Walt, for reporting the time-inaccuracy of mains-synched
clocks that I see. I'm glad you are far distant from me, and so you have
data from a new location and generation utility.
I last set all my appliance and mains-synched clocks late on March 9, to
advance the time for DST. I just checked and all the mains-synched
clocks roll the minute digit simultaneously and all are now about 24
seconds fast of GPS time after about two weeks. Historically here, the
mains clocks being fast is unusual; it is more common for them to run
slow. But, a 24 second error is not unusual.
I'm in Southern California and Walt is in Washington, also on the west
coast but not near me. So, this mains frequency effect on old clocks is
not local to my independent-utility city.
Please folks, stop quoting specs that may or may not still be valid and
may or may not be complied with by electric generation utilities.
Instead, let's get data!
I have long set all my appliance clocks to the second, even though they
don't display seconds. The final button-push in the time-setting command
will start the clock time at the zero second. Try it! Use a
known-accurate (e.g. GPS) clock and set your appliance clocks, then
check them again in a few days or more against your accurate clock.
Report the results and your location. That's data!
I bought one of the new-Heathkit LED clock kits a few years ago; this
new design is a mains-synched clock. I have never built that kit but I
was disappointed to hear user complaints that it did not keep accurate
time. In fact, though, those that were assembled may just have been
showing the same mains-frequency issue we are discussing.
There are some cell phone apps that will read the phone's GPS and show
time to the second. I use "Sol Et Umbra" (it's a sundial application)
and "Atomic Time," which shows a sweeping second hand; both are free and
Android apps.
I recommend the Geppetto GPS Clock offered on Tindie; its red LED
display (including tenth seconds) closely resembles that of the old
Heathkit GC-1000 clock; the latest versions access multi-GNSS signals.
Best wishes,
Larry McDavid W6FUB
Anaheim, California (SE of Los Angeles, near Disneyland)
On 3/25/2024 1:59 PM, Walt wrote:
You are not alone. I was intrigued by this thread, so I plugged in my
Heathkit GC-1005 mains-powered digital clock and set the time against my
PST-1030 WWV Time Clock.
I went outside to do some chores, and when I came back in 3 1/2 hours
later, I'll be darned if the clock was not 3.5 seconds ahead already!
Now
it's been almost 4 hours and the Heath is almost 4 seconds ahead.
...
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