http://www.tdipower.com/PDF/white_paper/TW0062.pdf
..page 8 of the following shows that Audio equipment is "Class A" equipment and included in EN61000-3-2 regulations on power factor.
....regarding the ripple current situation in the capacitors of 50Hz transformer based PSU's.......
...I am convinced that you will agree with me that the ripple current in the electrolytics in a 50Hz trafo-type supply will be far higher than in an equivalent power power-factor-corrected supply.
..so in the microwave oven with the 50Hz trafo based PSU that was described earlier.........the electrolytics must either be special low ESR ones, or their lifetime will be compromised.
You dont have to experiment to see how high the ripple current is in a 50Hz trafo based PSU.....just set it up on the LTspice free simulator and see for yourself.
.......and the problem with High power 50Hz PSU's, is that if you add enough electrolytic capacitance in parallel to get under the capacitor ripple current specification, then you violate mains harmonic current limits. (the limits are shown on page 8 of the above article)
PFC is mandatory for all PSU's above 75W that connect to the mains virtually anywhere in the world.....there are absolutely no exceptions
The Audio Power supplys that don't use PFC are breaking the Law.
For lighting, Power Factor correction is mandatory for anything above 25W that connects to the mains.
..page 8 of the following shows that Audio equipment is "Class A" equipment and included in EN61000-3-2 regulations on power factor.
....regarding the ripple current situation in the capacitors of 50Hz transformer based PSU's.......
...I am convinced that you will agree with me that the ripple current in the electrolytics in a 50Hz trafo-type supply will be far higher than in an equivalent power power-factor-corrected supply.
..so in the microwave oven with the 50Hz trafo based PSU that was described earlier.........the electrolytics must either be special low ESR ones, or their lifetime will be compromised.
You dont have to experiment to see how high the ripple current is in a 50Hz trafo based PSU.....just set it up on the LTspice free simulator and see for yourself.
.......and the problem with High power 50Hz PSU's, is that if you add enough electrolytic capacitance in parallel to get under the capacitor ripple current specification, then you violate mains harmonic current limits. (the limits are shown on page 8 of the above article)
PFC is mandatory for all PSU's above 75W that connect to the mains virtually anywhere in the world.....there are absolutely no exceptions
The Audio Power supplys that don't use PFC are breaking the Law.
For lighting, Power Factor correction is mandatory for anything above 25W that connects to the mains.
And you have anything to back this up with? Can you please show where in Canada this is so?
Never heard this one either.
USA and Canada governments have fully bought in to pretty much all of these electrical regulations....
lets face it, they have to because otherwise they'd be out of touch with the rest of the world, and wouldnt be able to sell products which the rest of the world would want.
.....Because of the 115VAC mains in USA.....currents are much higher , and so PFC becomes even more imprtant anyway.
Also, all the major semiconductor manufacturers in the USA (ti, National, Fairchildsemi etc) have huge production lines for acive power factor correction integrated circuits.
The USA actually leads the setting of "green" standards such as standby regulations....particularly the state of California which has its own hyped up standards.
Ive only seen standards docs at workplaces, ........its actually extremely difficult to find out, for example, where you could buy a copy of the EN61000 regulations.
....EN standards are European, but tend to be same as US equivalent etc
lets face it, they have to because otherwise they'd be out of touch with the rest of the world, and wouldnt be able to sell products which the rest of the world would want.
.....Because of the 115VAC mains in USA.....currents are much higher , and so PFC becomes even more imprtant anyway.
Also, all the major semiconductor manufacturers in the USA (ti, National, Fairchildsemi etc) have huge production lines for acive power factor correction integrated circuits.
The USA actually leads the setting of "green" standards such as standby regulations....particularly the state of California which has its own hyped up standards.
Ive only seen standards docs at workplaces, ........its actually extremely difficult to find out, for example, where you could buy a copy of the EN61000 regulations.
....EN standards are European, but tend to be same as US equivalent etc
Why would it be extremely difficult to find out if everyone was on the bandwagon? You would think it was no secret if they wanted manufacturers to comply.
http://www.powerphysics.com/lab-notes-journal/2010/8/10/what-is-power-factor-correction-pfc.html
And a long thread here
Electrical/Electronic engineering other topics - Why have Active PFC in Audio SMPS?
Both states that <600 Watt do not require PFC for audio use.
And a long thread here
Electrical/Electronic engineering other topics - Why have Active PFC in Audio SMPS?
Both states that <600 Watt do not require PFC for audio use.
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Kjeldsen....the eng-tips thread confirms that PFC is required.
Printer2:
The authorities that set the standards, are very close to the Test Labs that actually test products to check for compliance.
.......they dont particularly want companies to know what the standards exactly are.......that way, companies make mistakes, and have to modify their products and get them re-tested.......
...and yes, you've guessed it....They charge you lots of lovely lucre to test your product.......and when you have to get it re-tested because the first time round you werent clear what the standards actually were......you have to pay another load of money to them.
So money, as expected, comes into it, and the standards are very hard to find, and very hard to understand once you have found them......
as a result , you make mistakes , and end up paying out lots of money to them.
Printer2:
The authorities that set the standards, are very close to the Test Labs that actually test products to check for compliance.
.......they dont particularly want companies to know what the standards exactly are.......that way, companies make mistakes, and have to modify their products and get them re-tested.......
...and yes, you've guessed it....They charge you lots of lovely lucre to test your product.......and when you have to get it re-tested because the first time round you werent clear what the standards actually were......you have to pay another load of money to them.
So money, as expected, comes into it, and the standards are very hard to find, and very hard to understand once you have found them......
as a result , you make mistakes , and end up paying out lots of money to them.
That thread confirms that some people think it is, and some people think it isn't.
The over link posted suggests over 600W amplifiers, but then says "* The actual specification is for harmonic content and you have to calculate the amplifier power" - which is pretty vague?.
Neither of these are of course in any way official statements, just personal opinions.
The PowerPhysics site also suggests that high power audio amplifiers without PFC will blow the circuit protectors - yet in all the decades of high power audio amplifiers this has never happened?. Non-PFC 2000W RMS amplifiers (both SMPS and linear) are common place, yet don't blow circuit breakers.
EDIT: What a shock - I see PowerPhysics sell PFC amplifiers, presumably that's why they are making unfounded claims?.
Are you talking from knowledge or just making it up? My brother designs electronic equipment for a living and designs around specs outlined by the Canadian Standards Association (CSA). If it is not in a Standard then CSA can not just make up it up. They also can not hide information from manufacturers. Here is an example.
C22.2 NO. 14-10 - Industrial control equipment
C22.2 NO. 14-10 | Low Voltage Distribution and Control | ShopCSA
I doubt that manufacturers would buy the standards if the requirements they are to meet are not in them.
There are a couple of possibilities here.
One is that all the various amplifier manufacturers all over the world are in conspiracy to disregard important electrical rules and yet they get away with it, and all the regulating authorities are in on it and let them get away with it.
The other is that perhaps you have misunderstood the regulations.
One is that all the various amplifier manufacturers all over the world are in conspiracy to disregard important electrical rules and yet they get away with it, and all the regulating authorities are in on it and let them get away with it.
The other is that perhaps you have misunderstood the regulations.
With all regulatations there is a translation - that is how the regulations should be interpreted. There can also have been a lawcase that sets a standard on how certain specific products should be treated according to the regulations. My point, is that you can never just read the regulations, and then think you know all.
But try finding in the actual regulations where it says that your average power consumption for a guitar amplifier is 1/8 max.
....you cannot find it, -it isn't there....the "1/8 max power" thing that everyone keeps quoting is just what someone's dreamed up.
(oops...the post that i was responding to has just vanished)
....you cannot find it, -it isn't there....the "1/8 max power" thing that everyone keeps quoting is just what someone's dreamed up.
(oops...the post that i was responding to has just vanished)
The most precise info I can find, is that nothing is in writing, but that it is a common understanding that 1/8 of rated power is normal avg. usage. Since music is dynamic, that is probably correct. But, their will be a huge difference if it's soft jazz guitar or shredding death metal riffs.
I have been a sound engineer also for death metal bands. One guitarist had a 25 watt tube amp, and that was really loud.
I have been a sound engineer also for death metal bands. One guitarist had a 25 watt tube amp, and that was really loud.
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Distorted sound is FAR louder than clean sound, so a heavily distorted 25W valve amp is a VERY loud device indeed. You'd probably need at least a 100W transistor amp, fed from a fuzz pedal to give a similar effect, to be as loud.
A heavily over driven valve amp will output 50W or so anyway, and sound a LOT louder than a clean 50W.
A tube amp has a pretty good power factor already - The heater supply will reflect a purely resistive load. The HV supply will tend to be a little capacitive but not enough to swing the phase angle significantly. Thus in a typical tube amplifier there is little or nothing to correct.
I haven't read the Euro standard but if drafted by someone technically competent it would base its requirement for Power Factor Correction on the actual Power Factor, not on a power level. It would be rather pointless to insist upon power factor correction when power factor is better than say 0.85 to 0.9.
THis becomes more important when running equipment from an inverter or a switch mode supply where such a device must be rated for the apparent power draw and not the real power. These supplies do not really have a power factor of their own but will reflect the power factor of their load (broadly speaking).
Cheers,
Ian
I haven't read the Euro standard but if drafted by someone technically competent it would base its requirement for Power Factor Correction on the actual Power Factor, not on a power level. It would be rather pointless to insist upon power factor correction when power factor is better than say 0.85 to 0.9.
THis becomes more important when running equipment from an inverter or a switch mode supply where such a device must be rated for the apparent power draw and not the real power. These supplies do not really have a power factor of their own but will reflect the power factor of their load (broadly speaking).
Cheers,
Ian
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