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Bob Parker
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David
Suzy said:
Rather than rely on Phil's postulations, you may as well have the
*actual* figures for for eastern mainland and even Tasmania.
http://www.nemmco.com.au/powersystemops/250-0071.pdf
That was for Nov 2007, but there are older months on line if you poke
around. Also, you can see the actual state loads over 5 minutes on line,
and spot price for energy.
http://www.nemmco.com.au/data/GRAPH_5NSW1.htm
The frequency of the power grid will drop significantly when there is a
generator failure, and will stay low until the boilers on other plant
can catch up. This takes some time due to physical thermal constraints
on the plant. If the frequency drops too low, automatic load shedding
will drop some loads. Significant industrial loads are often load shed
in this way (ie the pot lines at Aluminum smelters etc)
The frequency of the grid will rise if there is a fault which reduces
load. This is typically caused by transmission line failure. If the
frequency of the generator rises too high, it risks damage due to over
speed, and will shut down. If as steam turbine generator shuts down, it
can take significant time (hours) to restart the boiler / generator, and
get it back to full load.
David
E
Elmo
Suzy said:
The voltage at your residence would tell you very little about the grid.
As well as voltage fluctuations caused by nearby loads, there are other
factors caused by reactive power that causes voltages to rise and fall.
Some power lines use capacitor banks to offset the inductance of long
transmission lines. This area is way over my head.
Elmo
B
bassett
O'dear, now you've upset poor phil, you see the problem is Suzy. he's
never had a girl friend, in fact the only woman that ever spoke to him is
the lady in the launderette and his mum, and there was a bag lady once
who rejected his body, But thats the nearest his come to actually having
sex with someone else. and she shot through, once she found he could
pull himself into shape. Then the Catholic Fathers took over, and he's
never been the same since. he does tend to go off, some think it's the
moon, others think he gets a memory relapse, from Father Murphy, but the
poor lov has these lapses, Don't talk about Quad, Toasters, or Aus Hi Fi
and you should be OK. Unless of cause your a catholic nun. And no-one
knows what would happen in that event.
Actually he's quite harmless, apart from the verbal abuse, stalking,
midnight phone calls, and curbside clean-up's where he changes his
belongings twice a year. he can often be heard calling out, "It's mine,
It's mine, I saw it first"
at times like this he should not be approached, Only his five friends are
welcome to call round his humble little hovel .
But attempting to get any reasonable conversation past the third post is
imposable, as his little mind just can't comprehend beyond the second
post, his attention span, is very limited to the point where he just
keeps repeating the insults until the respondent goes away. Or he gives
up, doesn't happen very often. But he's never had to deal with a woman's
logic, so it could all be quite interesting and entertaining.
A sort of war and peace, or the down fall of Phil, ground into the
ground, lost for an answer, beaten with kindness,
Anyway you just carry on.. We all sit waiting to witness the outcome.
bassett
never had a girl friend, in fact the only woman that ever spoke to him is
the lady in the launderette and his mum, and there was a bag lady once
who rejected his body, But thats the nearest his come to actually having
sex with someone else. and she shot through, once she found he could
pull himself into shape. Then the Catholic Fathers took over, and he's
never been the same since. he does tend to go off, some think it's the
moon, others think he gets a memory relapse, from Father Murphy, but the
poor lov has these lapses, Don't talk about Quad, Toasters, or Aus Hi Fi
and you should be OK. Unless of cause your a catholic nun. And no-one
knows what would happen in that event.
Actually he's quite harmless, apart from the verbal abuse, stalking,
midnight phone calls, and curbside clean-up's where he changes his
belongings twice a year. he can often be heard calling out, "It's mine,
It's mine, I saw it first"
at times like this he should not be approached, Only his five friends are
welcome to call round his humble little hovel .
But attempting to get any reasonable conversation past the third post is
imposable, as his little mind just can't comprehend beyond the second
post, his attention span, is very limited to the point where he just
keeps repeating the insults until the respondent goes away. Or he gives
up, doesn't happen very often. But he's never had to deal with a woman's
logic, so it could all be quite interesting and entertaining.
A sort of war and peace, or the down fall of Phil, ground into the
ground, lost for an answer, beaten with kindness,
Anyway you just carry on.. We all sit waiting to witness the outcome.
bassett
S
Suzy
Much as I expected, David. But I am a bit surprised about the pot lines...David said:
With my limited knowledge of metallurgy, I would have thought that switching
off the supply to a pot line causes all kinds of problems, and takes a long
time (and lots of energy) to clean up.
S
Suzy
David said:
Have just been looking at those sites, David. Excellent. From the first one,
it appears that frequency excursions *are* useful indicators. I think that I
can cope with frequency to voltage conversion in my proposed monitor (which
will work via a plugpack) , but I remain a bit dubious about calibrating and
checking it on a long term basis. Clearly synchronising to the actual mains
is a no no! GPS synchronisation looks best at this stage. Any other ideas
anyone? (not PA, back to the killfile to avoid boredom...)
S
Suzy
Thanks. Now I understand. It is sad. And from what you say I have "won" theTT said:Hi Suzy, I see you are at the stage where you thought you were having and
intelligent conversation with Philthy and then he suddenly flies into one
of his fetid rages.
I am a bit of an expert on this poor sad excuse for a person and I will
give you quick run down on his life, career etc and you will better
understand where he is coming from and you will be better able to cope
with him.
Phillip Martin Allison is about 55yo and an ex-Tasmanian with a retarded
sister. He went to Kogarah Marist Bros and apparently was good at maths
and science. He won a fully paid scholarship and enrolled in the faculty
of Engineering at Sydney Uni in 1971. Two years later he dropped out and
apparently (so rumour has it) there was an incident with a lecturer (male)
in an orchestra pit ;-) ;-).
Now to sum up, Philthy has *NO* qualifications of any sort. He does not
even have a driver's licence! He runs a home hobby business (not
registered for GST) from his bedsit in Summer Hill in Sydney where he
tinkers with small domestic appliances. It is even directly opposite a
Catholic Church!!! He is still (technically) a virgin, is unemployable and
suffers from Bipolarity. He abhors anyone with qualifications and if you
want a funny story ask him about his pal (?) Jim Prendergast who is a PhD.
Now Suzy picture this sad, pathetic creature with no friends, no life and
a meagre existence that only has Usenet as a contact with people. He will
(right now) be scouring the internet for any clue as to your identity and
any information about you. He is a *Net Stalker*!!! He has even *paid*
for company searches on poster's businesses in this group (and others) and
then rang and harassed business partners! He has even offered reward
money for information about people!
So please be very, very careful and *do not* give out any personal
information that will allow this creature to track you down!
If I can be of any further help please feel free to email me privately if
you prefer.
Cheers TT (Philthy's arch nemesis))
PS you will know when you have won the argument because all he does is cut
'n' paste the same abuse post after post ;-) Why he will even start new
headers with the same stuff! Sighhhhhhh............... Sad really, isn't
it?
argument. I'm sorry about that actually, because if he had the knowledge to
prove I was barking up the wrong tree, I would be glad to be corrected!
As for stalking etc, that would explain the silly references to chat rooms.
I've googled Suzy and there is indeed one who inhabits chat rooms and has an
unhealthy obsession. But it certainly isn't me, which would be obvious to an
intelligent person... Thanks again for the explanation, and especially the
virginity bit. If I'd known (rather than guessed) I might have been more
gentle...
S
Suzy
....> keeps repeating the insults until the respondent goes away. Or he
gives
Oh dear. I realise that might be the problem. And I can see that it might be
entertaining. It wouldn't be hard to demolish his "argument" especially from
my relatively ignorant but (thank goodness) stable stance. But I have no
wish to grind him into the ground. I just wondered if he knew anything about
mains frequency variations. Apparently not. I will once again consign him to
the killfile. Rather sadly actually. No-one is *all* bad, and I thought we
might have a sensible discussion there for a moment...
Sorry, not really my style.
gives
Oh dear. I realise that might be the problem. And I can see that it might be
entertaining. It wouldn't be hard to demolish his "argument" especially from
my relatively ignorant but (thank goodness) stable stance. But I have no
wish to grind him into the ground. I just wondered if he knew anything about
mains frequency variations. Apparently not. I will once again consign him to
the killfile. Rather sadly actually. No-one is *all* bad, and I thought we
might have a sensible discussion there for a moment...
Sorry, not really my style.
S
Suzy
Elmo said:
Ah, coming back to me now. Capacitor banks... All a bit over my head too!
B
Bob Parker
Back in about 1983 when I was watching the mains change in phase
relative to my comparatively stable ceramic resonator reference, it used
to gradually advance then retard over a period of minutes. It looked
like a slow feedback loop at work to me. I didn't see any consistent
increase or reduction in frequency at different times of the day. You'd
need to do a lot of averaging over a long period to see a clear trend.
Maybe things are different now ... but I'd have expected better
control of the network frequency these days, with improvements in
technology and communications in the network.
I'd have thought that was kind-of obvious. That's why I don't check
my frequency counter's accuracy by measuring its own crystal oscillator.
Sounds like a lot of effort to get a vague result which might or
might not give useful information. The last rolling blackouts I can
remember here in Sydney were in the 1970s, and that was due to strike
action, not hardware/capacity problems in the electricity network.
Good luck.
Bob
P
Phil Allison
"Suzy" <not@valid>
** **** OFF back to the moronic, narcissistic on line chat rooms you
normally infest !!
Where asinine, anonymous public masturbators put THEMSELVES at the
CENTRE of every topic.
Just like dumb TROLLS all do.
........ Phil
** **** OFF back to the moronic, narcissistic on line chat rooms you
normally infest !!
Where asinine, anonymous public masturbators put THEMSELVES at the
CENTRE of every topic.
Just like dumb TROLLS all do.
........ Phil
D
David L. Jones
It's still not going to give you any useful indication of when the
power is going to fail at *your* place. So what's the point measuring
this?, if as I gather your point is to predict blackouts and such?
Unpredictable local storms, car crashes, transformer failures, and
nearby local load switching are going to potentially cause you more
blackouts and/or brownouts.
Dave.
D
David
Suzy said:
The pot lines take *HUGE* amounts of energy, in Australia around 15% of
total supply. To refine 1 Tonne of Al, requires approx 15MWh of
electricity (which is why recycling Al is very cost effective).
For example, the Tomago Aluminium smelter in NSW, uses around 690MW of
power, and is supplied directly by Transgrid from its own 330KV
substation. The smelters also get heavily subsidised electricity, paying
around 1/3 of what other industries would be paying, (and much less than
you and I pay).
The pot lines can loose power for 4-5 hours without them solidifying. By
dropping and Al smelter load, the power system can quickly recover from
a loss of a generator. When replacement generation has ramped up, supply
can be restored. Their supply contracts do however require that power be
restored within a certain time, before the pot lines are in trouble, and
the maximum number of times they can be load shed etc. The pricing and
conditions was all very political to encourage (bribe?) the smelter
operators to build there smelters in the local area, and provide
employment etc.
David
B
Bob Parker
Now that's putting it into perspective.
My little UPS from Rockby Electronics [free plug] has saved me from
losing data quite a few times during brief interruptions caused by
storms and car accidents bringing down power lines in the local area.
Bob
J
John_H
Suzy said:
Think it was EA that ran a project for a TV derived frequency
reference around 15 years ago.
They claimed atomic clock accuracy, since that's what most, if not
all, of the commercial channels used to derive their horizontal sync.
I used one as a reference for a frequency counter, with good results,
up until our TV went digital (I'm on Optus satellite TV). Presumably
it would still work on ground based analogue transmissions (which I
don't get).
It was available as a kit IIRC.
B
Bob Parker
One crude way to watch what the mains frequency's doing is to be in
an area of poor (analog) TV reception where there are high voltage power
lines nearby.
Wait for a nice humid day when the insulators are crackling, then
watch a low VHF channel (Channel 2 is good) and watch what the
horizontal lines of RF noise from the insulators arcing are doing in the
picture. This is comparing the mains frequency against the very accurate
50Hz field rate timing of the TV station.
If the noise lines are moving up the picture, the mains frequency's
above 50Hz and vice versa. I think I got that the right way around.
You could use a stop watch to measure how long it takes for the
interference to do a complete 'loop' and do some calculating of the
exact mains frequency.
Bob
an area of poor (analog) TV reception where there are high voltage power
lines nearby.
Wait for a nice humid day when the insulators are crackling, then
watch a low VHF channel (Channel 2 is good) and watch what the
horizontal lines of RF noise from the insulators arcing are doing in the
picture. This is comparing the mains frequency against the very accurate
50Hz field rate timing of the TV station.
If the noise lines are moving up the picture, the mains frequency's
above 50Hz and vice versa. I think I got that the right way around.
You could use a stop watch to measure how long it takes for the
interference to do a complete 'loop' and do some calculating of the
exact mains frequency.
Bob
B
Bob Parker
Jim Rowe based it on a simple circuit I submitted as a Circuit and
Design Idea. ;-)
D
David L. Jones
One crude way to watch what the mains frequency's doing is to be in
an area of poor (analog) TV reception where there are high voltage power
lines nearby.
Wait for a nice humid day when the insulators are crackling, then
watch a low VHF channel (Channel 2 is good) and watch what the
horizontal lines of RF noise from the insulators arcing are doing in the
picture. This is comparing the mains frequency against the very accurate
50Hz field rate timing of the TV station.
If the noise lines are moving up the picture, the mains frequency's
above 50Hz and vice versa. I think I got that the right way around.
You could use a stop watch to measure how long it takes for the
interference to do a complete 'loop' and do some calculating of the
exact mains frequency.
Neat!
No HV lines within cooee of my place though, nor above ground power
lines for that matter.
Come to think of it, I don't have an analog TV any more, nor an analog
band antenna!
Dave.
B
Bob Parker
Thanks for the info, Michael.
Back then, Jim Rowe got the Australian Commonwealth Scientific and
Industrial Research Organisation (CSIRO) to do some precise measurements
of his TV-derived frequency standard.
They found that all the networks were very accurate, but a couple
were super-precise. Maybe it's all different now and GPS is the way to go?
Bob
B
Bob Parker
Darn! Now you won't know when the next blackout due to the network
being overloaded is going to happen.
Bob
