EDAboard.com | EDAboard.de | EDAboard.co.uk | WTWH Media

Power factor and domestic electricity billing in the UK?

Ask a question - edaboard.com

elektroda.net NewsGroups Forum Index - Electronics - Power factor and domestic electricity billing in the UK?

Goto page 1, 2, 3, 4  Next

Uncle Peter
Guest

Thu Apr 17, 2014 6:07 am   



Can someone confirm that power factor is NOT taken into consideration for domestic supplies? I have a feeling it isn't, but I can't find any information on the internet. If it matters, it's a modern (<5 years old) electronic meter I have. The power factor in my house is an average of 0.7 so depending if it's charged for or not, my bill could be completely different.

--
Tip: Don't substitute salt for sugar in recipes.
It tastes like shit.

Daniel
Guest

Thu Apr 17, 2014 6:50 pm   



On 17/04/14 10:07, Uncle Peter wrote:
Quote:
Can someone confirm that power factor is NOT taken into consideration
for domestic supplies? I have a feeling it isn't, but I can't find any
information on the internet. If it matters, it's a modern (<5 years
old) electronic meter I have. The power factor in my house is an
average of 0.7 so depending if it's charged for or not, my bill could be
completely different.

When I last dealt with this, power generator companies "assumed" there
would be an average power factor and set up their generators to handle
that. Your individual house (or, probably, even a small factory) would
not cause much variation in that power factor, considering the
generators are probably supplying hundreds of thousands of homes at the
same time!!

Daniel

Uncle Peter
Guest

Thu Apr 17, 2014 7:46 pm   



On Thu, 17 Apr 2014 13:50:32 +0100, Daniel <dxmm_at_albury.nospam.net.au> wrote:

Quote:
On 17/04/14 10:07, Uncle Peter wrote:
Can someone confirm that power factor is NOT taken into consideration
for domestic supplies? I have a feeling it isn't, but I can't find any
information on the internet. If it matters, it's a modern (<5 years
old) electronic meter I have. The power factor in my house is an
average of 0.7 so depending if it's charged for or not, my bill could be
completely different.

When I last dealt with this, power generator companies "assumed" there
would be an average power factor and set up their generators to handle
that. Your individual house (or, probably, even a small factory) would
not cause much variation in that power factor, considering the
generators are probably supplying hundreds of thousands of homes at the
same time!!


That won't apply to switched mode power supplies clipping off the peaks though.

--
Is a castrated pig disgruntled?

Daniel
Guest

Fri Apr 18, 2014 5:48 pm   



On 17/04/14 23:46, Uncle Peter wrote:
Quote:
On Thu, 17 Apr 2014 13:50:32 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 17/04/14 10:07, Uncle Peter wrote:
Can someone confirm that power factor is NOT taken into consideration
for domestic supplies? I have a feeling it isn't, but I can't find any
information on the internet. If it matters, it's a modern (<5 years
old) electronic meter I have. The power factor in my house is an
average of 0.7 so depending if it's charged for or not, my bill could be
completely different.

When I last dealt with this, power generator companies "assumed" there
would be an average power factor and set up their generators to handle
that. Your individual house (or, probably, even a small factory) would
not cause much variation in that power factor, considering the
generators are probably supplying hundreds of thousands of homes at the
same time!!

That won't apply to switched mode power supplies clipping off the peaks
though.

Wouldn't cause a very big blip in the grander scheme of things.


And what SMPS clips off the peaks?? Usually they vary the switch on
point in the A.C. waveform.

Daniel

Uncle Peter
Guest

Fri Apr 18, 2014 6:45 pm   



On Fri, 18 Apr 2014 12:48:36 +0100, Daniel <dxmm_at_albury.nospam.net.au> wrote:

Quote:
On 17/04/14 23:46, Uncle Peter wrote:
On Thu, 17 Apr 2014 13:50:32 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 17/04/14 10:07, Uncle Peter wrote:
Can someone confirm that power factor is NOT taken into consideration
for domestic supplies? I have a feeling it isn't, but I can't find any
information on the internet. If it matters, it's a modern (<5 years
old) electronic meter I have. The power factor in my house is an
average of 0.7 so depending if it's charged for or not, my bill could be
completely different.

When I last dealt with this, power generator companies "assumed" there
would be an average power factor and set up their generators to handle
that. Your individual house (or, probably, even a small factory) would
not cause much variation in that power factor, considering the
generators are probably supplying hundreds of thousands of homes at the
same time!!

That won't apply to switched mode power supplies clipping off the peaks
though.

Wouldn't cause a very big blip in the grander scheme of things.

And what SMPS clips off the peaks?? Usually they vary the switch on
point in the A.C. waveform.


You can get power supplies with "active PFC" which is presumably what you just described. However the cheap ones have "passive PFC" or no PFC, so presumably they just top up the bulk capacitors at the peak of each waveform. A basic transformer and rectifier will do the same.

--
A patient tells the Doctor, "I've been going to a faith healer, but wasn't getting any better."
The Doctor smiled and said, "And what dumb advice did this phony give you?"
"He told me to come see you." replied the new patient.

Daniel
Guest

Sun Apr 20, 2014 5:17 pm   



On 18/04/14 22:45, Uncle Peter wrote:
Quote:
On Fri, 18 Apr 2014 12:48:36 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 17/04/14 23:46, Uncle Peter wrote:
On Thu, 17 Apr 2014 13:50:32 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 17/04/14 10:07, Uncle Peter wrote:
Can someone confirm that power factor is NOT taken into consideration
for domestic supplies? I have a feeling it isn't, but I can't find
any
information on the internet. If it matters, it's a modern (<5 years
old) electronic meter I have. The power factor in my house is an
average of 0.7 so depending if it's charged for or not, my bill
could be
completely different.

When I last dealt with this, power generator companies "assumed" there
would be an average power factor and set up their generators to handle
that. Your individual house (or, probably, even a small factory) would
not cause much variation in that power factor, considering the
generators are probably supplying hundreds of thousands of homes at the
same time!!

That won't apply to switched mode power supplies clipping off the peaks
though.

Wouldn't cause a very big blip in the grander scheme of things.

And what SMPS clips off the peaks?? Usually they vary the switch on
point in the A.C. waveform.

You can get power supplies with "active PFC" which is presumably what
you just described. However the cheap ones have "passive PFC" or no
PFC, so presumably they just top up the bulk capacitors at the peak of
each waveform. A basic transformer and rectifier will do the same.

What's "PFC" when it's at home?? Power Factor Correction maybe!!


To the mains supply, most things look like Inductors, which means the
voltage waveform and the current waveforms are not in phase. Power
Factor Correction simple means that capacitors are switched in to
counter-act the Inductance, so the Voltage and Current are more nearly
in phase.

Active PFC might be changing how a transistor "appears" (more capacitive
or less capacitive) to fix the phase angle.

And, as I typed earlier, your little power supply would have very little
effect on the phase angle of your homes mains supply!!

Now, when your refrigerator's (inductive) motor switches on, now that
might have a noticeably affect, but, in the greater scheme of your
regional Power companies operations, zero effect!!

Daniel

Uncle Peter
Guest

Mon Apr 21, 2014 1:03 am   



On Sun, 20 Apr 2014 12:17:45 +0100, Daniel <dxmm_at_albury.nospam.net.au> wrote:

Quote:
On 18/04/14 22:45, Uncle Peter wrote:
On Fri, 18 Apr 2014 12:48:36 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 17/04/14 23:46, Uncle Peter wrote:
On Thu, 17 Apr 2014 13:50:32 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 17/04/14 10:07, Uncle Peter wrote:

When I last dealt with this, power generator companies "assumed" there
would be an average power factor and set up their generators to handle
that. Your individual house (or, probably, even a small factory) would
not cause much variation in that power factor, considering the
generators are probably supplying hundreds of thousands of homes at the
same time!!

That won't apply to switched mode power supplies clipping off the peaks
though.

Wouldn't cause a very big blip in the grander scheme of things.

And what SMPS clips off the peaks?? Usually they vary the switch on
point in the A.C. waveform.

You can get power supplies with "active PFC" which is presumably what
you just described. However the cheap ones have "passive PFC" or no
PFC, so presumably they just top up the bulk capacitors at the peak of
each waveform. A basic transformer and rectifier will do the same.

What's "PFC" when it's at home?? Power Factor Correction maybe!!


I know that.

Quote:
To the mains supply, most things look like Inductors, which means the
voltage waveform and the current waveforms are not in phase. Power
Factor Correction simple means that capacitors are switched in to
counter-act the Inductance, so the Voltage and Current are more nearly
in phase.


And at different power level draws from the output of the power supply, presumably a different capacitance is ended to correct it. Active PFC probably changes it accordingly. Or adjusts the other type of power factor which you haven't mentioned - wave clipping.

Quote:
Active PFC might be changing how a transistor "appears" (more capacitive
or less capacitive) to fix the phase angle.

And, as I typed earlier, your little power supply would have very little
effect on the phase angle of your homes mains supply!!


How about ten 850W power supplies?

Quote:
Now, when your refrigerator's (inductive) motor switches on, now that
might have a noticeably affect, but, in the greater scheme of your
regional Power companies operations, zero effect!!


Or my industrial grade meat freezer.

--
You can't convince a believer of anything; for their belief is not based on evidence, it's based on a deep-seated need to believe. -- Carl Sagan


Guest

Mon Apr 21, 2014 3:12 am   



On Sun, 20 Apr 2014, Uncle Peter wrote:
Quote:
--
You can't convince a believer of anything; for their belief is not based on
evidence, it's based on a deep-seated need to believe. -- Carl Sagan


Look! There are no real mathematicians working on that! -- Carl Sagan,
refering to meta-logics (i.e. Goedel's incompleteness theorems).

TBA indeed

Daniel
Guest

Mon Apr 21, 2014 5:22 pm   



On 21/04/14 05:03, Uncle Peter wrote:
Quote:
On Sun, 20 Apr 2014 12:17:45 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 18/04/14 22:45, Uncle Peter wrote:
On Fri, 18 Apr 2014 12:48:36 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 17/04/14 23:46, Uncle Peter wrote:
On Thu, 17 Apr 2014 13:50:32 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 17/04/14 10:07, Uncle Peter wrote:

When I last dealt with this, power generator companies "assumed"
there
would be an average power factor and set up their generators to
handle
that. Your individual house (or, probably, even a small factory)
would
not cause much variation in that power factor, considering the
generators are probably supplying hundreds of thousands of homes
at the
same time!!

That won't apply to switched mode power supplies clipping off the
peaks
though.

Wouldn't cause a very big blip in the grander scheme of things.

And what SMPS clips off the peaks?? Usually they vary the switch on
point in the A.C. waveform.

You can get power supplies with "active PFC" which is presumably what
you just described. However the cheap ones have "passive PFC" or no
PFC, so presumably they just top up the bulk capacitors at the peak of
each waveform. A basic transformer and rectifier will do the same.

What's "PFC" when it's at home?? Power Factor Correction maybe!!

I know that.


But *I* didn't, which is why I asked "What's "PFC" when it's at home??"

Quote:
To the mains supply, most things look like Inductors, which means the
voltage waveform and the current waveforms are not in phase. Power
Factor Correction simple means that capacitors are switched in to
counter-act the Inductance, so the Voltage and Current are more nearly
in phase.

And at different power level draws from the output of the power supply,
presumably a different capacitance is ended to correct it. Active PFC
probably changes it accordingly. Or adjusts the other type of power
factor which you haven't mentioned - wave clipping.


I'm guessing just one, very big, capacitor which can handle the
filtering task for all loads up to the Power Supply's rating.

Quote:
Active PFC might be changing how a transistor "appears" (more capacitive
or less capacitive) to fix the phase angle.

And, as I typed earlier, your little power supply would have very little
effect on the phase angle of your homes mains supply!!

How about ten 850W power supplies?


10 x 850 watt power supplies, total 8.5kW, from a 240V supply takes
about 35Amps, .... and lets double that to allow for transformer and
other circuitry loses = 70Amps!! Whoopee!! from your regional Power
Company, which probably supplies THOUSANDS of Amps!!

Quote:
Now, when your refrigerator's (inductive) motor switches on, now that
might have a noticeably affect, but, in the greater scheme of your
regional Power companies operations, zero effect!!

Or my industrial grade meat freezer.


What's that, another 10kW!! WOW!! or rather Whoopee!! And remember the
freezer motor is not working 24/7 (or at least it shouldn't be), so its
real power consumption would be much lower, maybe 1kW at most!!

Daniel

Uncle Peter
Guest

Tue Apr 22, 2014 12:26 am   



On Mon, 21 Apr 2014 12:22:39 +0100, Daniel <dxmm_at_albury.nospam.net.au> wrote:

Quote:
On 21/04/14 05:03, Uncle Peter wrote:
On Sun, 20 Apr 2014 12:17:45 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 18/04/14 22:45, Uncle Peter wrote:
On Fri, 18 Apr 2014 12:48:36 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 17/04/14 23:46, Uncle Peter wrote:



Wouldn't cause a very big blip in the grander scheme of things.

And what SMPS clips off the peaks?? Usually they vary the switch on
point in the A.C. waveform.

You can get power supplies with "active PFC" which is presumably what
you just described. However the cheap ones have "passive PFC" or no
PFC, so presumably they just top up the bulk capacitors at the peak of
each waveform. A basic transformer and rectifier will do the same.

What's "PFC" when it's at home?? Power Factor Correction maybe!!

I know that.

But *I* didn't, which is why I asked "What's "PFC" when it's at home??"


When you immediately answered yourself, with two shriek marks, I assumed you were telling me.

Quote:
To the mains supply, most things look like Inductors, which means the
voltage waveform and the current waveforms are not in phase. Power
Factor Correction simple means that capacitors are switched in to
counter-act the Inductance, so the Voltage and Current are more nearly
in phase.

And at different power level draws from the output of the power supply,
presumably a different capacitance is ended to correct it. Active PFC
probably changes it accordingly. Or adjusts the other type of power
factor which you haven't mentioned - wave clipping.

I'm guessing just one, very big, capacitor which can handle the
filtering task for all loads up to the Power Supply's rating.


But surely if it's not adjusted, then it's overcompensating when the supply is not fully loaded.

Quote:
Active PFC might be changing how a transistor "appears" (more capacitive
or less capacitive) to fix the phase angle.

And, as I typed earlier, your little power supply would have very little
effect on the phase angle of your homes mains supply!!

How about ten 850W power supplies?

10 x 850 watt power supplies, total 8.5kW, from a 240V supply takes
about 35Amps, .... and lets double that to allow for transformer and
other circuitry loses = 70Amps!! Whoopee!! from your regional Power
Company, which probably supplies THOUSANDS of Amps!!


You said "very little effect on the phase angle of your homes mains supply!!" It's probably 90% of my home's supply.

Quote:
Now, when your refrigerator's (inductive) motor switches on, now that
might have a noticeably affect, but, in the greater scheme of your
regional Power companies operations, zero effect!!

Or my industrial grade meat freezer.

What's that, another 10kW!! WOW!! or rather Whoopee!! And remember the
freezer motor is not working 24/7 (or at least it shouldn't be), so its
real power consumption would be much lower, maybe 1kW at most!!


Yes, I was just pointing out I have a ridiculous freezer.

--
English > German
Indicators ---- Die Blinkenleiten Tickentocken
Bonnet ---- Pullnob und Knucklechopper
Exhaust ---- Die Spitzenpoppenbangentuben
Speedometer ---- Der Egobooster und Linenshooter
Clutch ---- Die Kuplink mit schlippen und shaken
Puncture ---- Die Phlatt mit Bludyfucken
Learner Driver ---- Die Twatten mit Elplatz
Estate Car ---- Der Bagmooroomfurshagginauto
Parking Meter ---- Der Tennerpinscher und Klockenwerr
Windscreen Wiper ---- Der Flippenflappenmuckenschpredder
Footbrake ---- Der Edbangeronvindschreen Stoppend
Gear Lever ---- Biggen Sticken fur Kangaroochoppen
Breathalyser ---- Die Pu titintem fur Pistenarsen
Seat Belt ---- Der Klunkenklikker Frauleintrapper
Headlights ---- Das Dippendontdazzleyubastad
Exhaust Fumes ---- Der Koffenundschpittpoluter
Highway Code ---- Der Wipan fur Arsen
Fog Warning ---- Die Puttenlegdownen und Fukkit
Traffic Jam ---- Die Bluddifukkink Dammundblast
Rear Seat ---- Der Schpringentester
Backfire ---- Der Lowdenbangenmekkenjumpen
Articulated Lorry ---- Der Fukkengrett Trukken
Accident ---- Der Bleedinmess
Near Accident ---- Der Fukken Near Schittsenselfen
Service Station ---- Der Heiway Robberungen
Cyclist ---- Der Pedallpushink Pilloken
Double White lines ---- Overtakenund Krunchen

Daniel
Guest

Tue Apr 22, 2014 4:00 pm   



On 22/04/14 04:26, Uncle Peter wrote:
Quote:
On Mon, 21 Apr 2014 12:22:39 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 21/04/14 05:03, Uncle Peter wrote:
On Sun, 20 Apr 2014 12:17:45 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 18/04/14 22:45, Uncle Peter wrote:
On Fri, 18 Apr 2014 12:48:36 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 17/04/14 23:46, Uncle Peter wrote:



Wouldn't cause a very big blip in the grander scheme of things.

And what SMPS clips off the peaks?? Usually they vary the switch on
point in the A.C. waveform.

You can get power supplies with "active PFC" which is presumably what
you just described. However the cheap ones have "passive PFC" or no
PFC, so presumably they just top up the bulk capacitors at the peak of
each waveform. A basic transformer and rectifier will do the same.

What's "PFC" when it's at home?? Power Factor Correction maybe!!

I know that.

But *I* didn't, which is why I asked "What's "PFC" when it's at home??"

When you immediately answered yourself, with two shriek marks, I assumed
you were telling me.


What part of the world are you from?? In some parts of the world, the
first thing people might think when they hear "PFC" would be "Private
First Class"!!

Quote:
To the mains supply, most things look like Inductors, which means the
voltage waveform and the current waveforms are not in phase. Power
Factor Correction simple means that capacitors are switched in to
counter-act the Inductance, so the Voltage and Current are more nearly
in phase.

And at different power level draws from the output of the power supply,
presumably a different capacitance is ended to correct it. Active PFC
probably changes it accordingly. Or adjusts the other type of power
factor which you haven't mentioned - wave clipping.

I'm guessing just one, very big, capacitor which can handle the
filtering task for all loads up to the Power Supply's rating.

But surely if it's not adjusted, then it's overcompensating when the
supply is not fully loaded.


No, in a Switched Mode Power Supply, as the load varies, it is *Switched
On* for more of less of the Alternating Cycle. If the supply's output
(Current/Voltage) is falling below the required (Current/Voltage), the
Switching element/transistor is switched on for more of the input cycle,
not the input voltage!!

Quote:
Active PFC might be changing how a transistor "appears" (more
capacitive
or less capacitive) to fix the phase angle.

And, as I typed earlier, your little power supply would have very
little
effect on the phase angle of your homes mains supply!!

How about ten 850W power supplies?

10 x 850 watt power supplies, total 8.5kW, from a 240V supply takes
about 35Amps, .... and lets double that to allow for transformer and
other circuitry loses = 70Amps!! Whoopee!! from your regional Power
Company, which probably supplies THOUSANDS of Amps!!

You said "very little effect on the phase angle of your homes mains
supply!!" It's probably 90% of my home's supply.


At some particular moment, you might be correct that the power supply is
having this great effect, but over a day/week I doubt it would be
anything like 90%!

Quote:
Now, when your refrigerator's (inductive) motor switches on, now that
might have a noticeably affect, but, in the greater scheme of your
regional Power companies operations, zero effect!!

Or my industrial grade meat freezer.

What's that, another 10kW!! WOW!! or rather Whoopee!! And remember the
freezer motor is not working 24/7 (or at least it shouldn't be), so its
real power consumption would be much lower, maybe 1kW at most!!

Yes, I was just pointing out I have a ridiculous freezer.

Wacko!!


Daniel

Uncle Peter
Guest

Wed Apr 23, 2014 3:01 am   



On Tue, 22 Apr 2014 11:00:36 +0100, Daniel <dxmm_at_albury.nospam.net.au> wrote:

Quote:
On 22/04/14 04:26, Uncle Peter wrote:
On Mon, 21 Apr 2014 12:22:39 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 21/04/14 05:03, Uncle Peter wrote:
On Sun, 20 Apr 2014 12:17:45 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 18/04/14 22:45, Uncle Peter wrote:





What's "PFC" when it's at home?? Power Factor Correction maybe!!

I know that.

But *I* didn't, which is why I asked "What's "PFC" when it's at home??"

When you immediately answered yourself, with two shriek marks, I assumed
you were telling me.

What part of the world are you from?? In some parts of the world, the
first thing people might think when they hear "PFC" would be "Private
First Class"!!


Only if they're military.

Quote:
To the mains supply, most things look like Inductors, which means the
voltage waveform and the current waveforms are not in phase. Power
Factor Correction simple means that capacitors are switched in to
counter-act the Inductance, so the Voltage and Current are more nearly
in phase.

And at different power level draws from the output of the power supply,
presumably a different capacitance is ended to correct it. Active PFC
probably changes it accordingly. Or adjusts the other type of power
factor which you haven't mentioned - wave clipping.

I'm guessing just one, very big, capacitor which can handle the
filtering task for all loads up to the Power Supply's rating.

But surely if it's not adjusted, then it's overcompensating when the
supply is not fully loaded.

No, in a Switched Mode Power Supply, as the load varies, it is *Switched
On* for more of less of the Alternating Cycle. If the supply's output
(Current/Voltage) is falling below the required (Current/Voltage), the
Switching element/transistor is switched on for more of the input cycle,
not the input voltage!!


I see. So this is seperate from the yellow one connected across the mains input?

Quote:
Active PFC might be changing how a transistor "appears" (more
capacitive
or less capacitive) to fix the phase angle.

And, as I typed earlier, your little power supply would have very
little
effect on the phase angle of your homes mains supply!!

How about ten 850W power supplies?

10 x 850 watt power supplies, total 8.5kW, from a 240V supply takes
about 35Amps, .... and lets double that to allow for transformer and
other circuitry loses = 70Amps!! Whoopee!! from your regional Power
Company, which probably supplies THOUSANDS of Amps!!

You said "very little effect on the phase angle of your homes mains
supply!!" It's probably 90% of my home's supply.

At some particular moment, you might be correct that the power supply is
having this great effect, but over a day/week I doubt it would be
anything like 90%!


It is. Those things run 24/7.

Quote:
Now, when your refrigerator's (inductive) motor switches on, now that
might have a noticeably affect, but, in the greater scheme of your
regional Power companies operations, zero effect!!

Or my industrial grade meat freezer.

What's that, another 10kW!! WOW!! or rather Whoopee!! And remember the
freezer motor is not working 24/7 (or at least it shouldn't be), so its
real power consumption would be much lower, maybe 1kW at most!!

Yes, I was just pointing out I have a ridiculous freezer.

Wacko!!


It hasn't got food in it.

--
What's a diaphragm?
A trampoline for dickheads.

Daniel
Guest

Wed Apr 23, 2014 6:20 pm   



On 23/04/14 07:01, Uncle Peter wrote:
Quote:
On Tue, 22 Apr 2014 11:00:36 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 22/04/14 04:26, Uncle Peter wrote:
On Mon, 21 Apr 2014 12:22:39 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 21/04/14 05:03, Uncle Peter wrote:
On Sun, 20 Apr 2014 12:17:45 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 18/04/14 22:45, Uncle Peter wrote:





What's "PFC" when it's at home?? Power Factor Correction maybe!!

I know that.

But *I* didn't, which is why I asked "What's "PFC" when it's at home??"

When you immediately answered yourself, with two shriek marks, I assumed
you were telling me.

What part of the world are you from?? In some parts of the world, the
first thing people might think when they hear "PFC" would be "Private
First Class"!!

Only if they're military.

To the mains supply, most things look like Inductors, which means the
voltage waveform and the current waveforms are not in phase. Power
Factor Correction simple means that capacitors are switched in to
counter-act the Inductance, so the Voltage and Current are more
nearly
in phase.

And at different power level draws from the output of the power
supply,
presumably a different capacitance is ended to correct it. Active PFC
probably changes it accordingly. Or adjusts the other type of power
factor which you haven't mentioned - wave clipping.

I'm guessing just one, very big, capacitor which can handle the
filtering task for all loads up to the Power Supply's rating.

But surely if it's not adjusted, then it's overcompensating when the
supply is not fully loaded.

No, in a Switched Mode Power Supply, as the load varies, it is *Switched
On* for more of less of the Alternating Cycle. If the supply's output
(Current/Voltage) is falling below the required (Current/Voltage), the
Switching element/transistor is switched on for more of the input cycle,
not the input voltage!!

I see. So this is seperate from the yellow one connected across the
mains input?


Yes, the "yellow one connected across the mains input" is a bridge
rectifier, which converts the AC Sinewave input into single polarity
pulses at twice the mains supply frequency.

Quote:
Active PFC might be changing how a transistor "appears" (more
capacitive
or less capacitive) to fix the phase angle.

And, as I typed earlier, your little power supply would have very
little
effect on the phase angle of your homes mains supply!!

How about ten 850W power supplies?

10 x 850 watt power supplies, total 8.5kW, from a 240V supply takes
about 35Amps, .... and lets double that to allow for transformer and
other circuitry loses = 70Amps!! Whoopee!! from your regional Power
Company, which probably supplies THOUSANDS of Amps!!

You said "very little effect on the phase angle of your homes mains
supply!!" It's probably 90% of my home's supply.

At some particular moment, you might be correct that the power supply is
having this great effect, but over a day/week I doubt it would be
anything like 90%!

It is. Those things run 24/7.


Do you switch on lights at night?? That'll effect the mains supply current.
Do you have a refrigerator that turns on and off?? That'll effect the
mains supply current.
How about a heater/electric blanket, etc., etc., etc.

Quote:
Now, when your refrigerator's (inductive) motor switches on, now that
might have a noticeably affect, but, in the greater scheme of your
regional Power companies operations, zero effect!!

Or my industrial grade meat freezer.

What's that, another 10kW!! WOW!! or rather Whoopee!! And remember the
freezer motor is not working 24/7 (or at least it shouldn't be), so its
real power consumption would be much lower, maybe 1kW at most!!

Yes, I was just pointing out I have a ridiculous freezer.

Wacko!!

It hasn't got food in it.

So what's it doing "On", apart from wasting energy??


Uncle Peter
Guest

Thu Apr 24, 2014 12:06 am   



On Wed, 23 Apr 2014 13:20:40 +0100, Daniel <dxmm_at_albury.nospam.net.au> wrote:

Quote:
On 23/04/14 07:01, Uncle Peter wrote:
On Tue, 22 Apr 2014 11:00:36 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 22/04/14 04:26, Uncle Peter wrote:
On Mon, 21 Apr 2014 12:22:39 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 21/04/14 05:03, Uncle Peter wrote:








But *I* didn't, which is why I asked "What's "PFC" when it's at home??"

When you immediately answered yourself, with two shriek marks, I assumed
you were telling me.

What part of the world are you from?? In some parts of the world, the
first thing people might think when they hear "PFC" would be "Private
First Class"!!

Only if they're military.



I'm guessing just one, very big, capacitor which can handle the
filtering task for all loads up to the Power Supply's rating.

But surely if it's not adjusted, then it's overcompensating when the
supply is not fully loaded.

No, in a Switched Mode Power Supply, as the load varies, it is *Switched
On* for more of less of the Alternating Cycle. If the supply's output
(Current/Voltage) is falling below the required (Current/Voltage), the
Switching element/transistor is switched on for more of the input cycle,
not the input voltage!!

I see. So this is seperate from the yellow one connected across the
mains input?

Yes, the "yellow one connected across the mains input" is a bridge
rectifier, which converts the AC Sinewave input into single polarity
pulses at twice the mains supply frequency.


No it isn't, I mean these ones: http://www.o-digital.com/uploads/2179/2184-1/Capacitor_X2_358.jpg

Quote:
10 x 850 watt power supplies, total 8.5kW, from a 240V supply takes
about 35Amps, .... and lets double that to allow for transformer and
other circuitry loses = 70Amps!! Whoopee!! from your regional Power
Company, which probably supplies THOUSANDS of Amps!!

You said "very little effect on the phase angle of your homes mains
supply!!" It's probably 90% of my home's supply.

At some particular moment, you might be correct that the power supply is
having this great effect, but over a day/week I doubt it would be
anything like 90%!

It is. Those things run 24/7.

Do you switch on lights at night?? That'll effect the mains supply current.
Do you have a refrigerator that turns on and off?? That'll effect the
mains supply current.
How about a heater/electric blanket, etc., etc., etc.


Nothing like the kW used by those PSUs.

Quote:
What's that, another 10kW!! WOW!! or rather Whoopee!! And remember the
freezer motor is not working 24/7 (or at least it shouldn't be), so its
real power consumption would be much lower, maybe 1kW at most!!

Yes, I was just pointing out I have a ridiculous freezer.

Wacko!!

It hasn't got food in it.

So what's it doing "On", apart from wasting energy??


Keeping water cool.

--
My childbirth instructor says it's not pain I'll feel during labour, but pressure. Is she right?
Yes, in the same way that a tornado might be called an air current.

Daniel
Guest

Thu Apr 24, 2014 6:59 pm   



On 24/04/14 04:06, Uncle Peter wrote:
Quote:
On Wed, 23 Apr 2014 13:20:40 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 23/04/14 07:01, Uncle Peter wrote:
On Tue, 22 Apr 2014 11:00:36 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 22/04/14 04:26, Uncle Peter wrote:
On Mon, 21 Apr 2014 12:22:39 +0100, Daniel <dxmm_at_albury.nospam.net.au
wrote:

On 21/04/14 05:03, Uncle Peter wrote:








But *I* didn't, which is why I asked "What's "PFC" when it's at
home??"

When you immediately answered yourself, with two shriek marks, I
assumed
you were telling me.

What part of the world are you from?? In some parts of the world, the
first thing people might think when they hear "PFC" would be "Private
First Class"!!

Only if they're military.



I'm guessing just one, very big, capacitor which can handle the
filtering task for all loads up to the Power Supply's rating.

But surely if it's not adjusted, then it's overcompensating when the
supply is not fully loaded.

No, in a Switched Mode Power Supply, as the load varies, it is
*Switched
On* for more of less of the Alternating Cycle. If the supply's output
(Current/Voltage) is falling below the required (Current/Voltage), the
Switching element/transistor is switched on for more of the input
cycle,
not the input voltage!!

I see. So this is seperate from the yellow one connected across the
mains input?

Yes, the "yellow one connected across the mains input" is a bridge
rectifier, which converts the AC Sinewave input into single polarity
pulses at twice the mains supply frequency.

No it isn't, I mean these ones:
http://www.o-digital.com/uploads/2179/2184-1/Capacitor_X2_358.jpg


Sorry, my mistake.

Quote:
10 x 850 watt power supplies, total 8.5kW, from a 240V supply takes
about 35Amps, .... and lets double that to allow for transformer and
other circuitry loses = 70Amps!! Whoopee!! from your regional Power
Company, which probably supplies THOUSANDS of Amps!!


<Snip>

Quote:
Yes, I was just pointing out I have a ridiculous freezer.

Wacko!!

It hasn't got food in it.

So what's it doing "On", apart from wasting energy??

Keeping water cool.


How much water, and for what purpose??

Daniel

Goto page 1, 2, 3, 4  Next

elektroda.net NewsGroups Forum Index - Electronics - Power factor and domestic electricity billing in the UK?

Ask a question - edaboard.com

Arabic version Bulgarian version Catalan version Czech version Danish version German version Greek version English version Spanish version Finnish version French version Hindi version Croatian version Indonesian version Italian version Hebrew version Japanese version Korean version Lithuanian version Latvian version Dutch version Norwegian version Polish version Portuguese version Romanian version Russian version Slovak version Slovenian version Serbian version Swedish version Tagalog version Ukrainian version Vietnamese version Chinese version Turkish version
EDAboard.com map