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More Regurgitated drivel We hate you Philis

Phil Allis> Feb 20, 2007.

Thought it didn't come out for another week or so, how did you get the inside goss?

BTW, did anyone ever post that infamous SC editorial about Aus.Electronics?

Dave :)

"David L. Jones" "Phil Allison"

** See:

At the end of the intro paras.

....... Phil

The ElectroCap bulging looks like one of the faulty batch we experienced in computers a while ago. Same colour and appears to be same brand...

Pity the person who wrote this article has no idea about power generation and system losses. Actual system losses in NSW for Transgrid was 2.7% for year ended 30/6/06, and for Integral Energy 4.96%, giving a total system loss for Integral Energy customers of 7.7%. Claiming "distribution losses can reach 20% easily (and I have even heard as high as 50% in some cases where extremely long feeders [several hundred kilometres] are used)" is totally wrong.

Also the article states:"A (now empty) CFL pack I have states the colour temperature as 3500K, and says that the lamps are 8W (equivalent to

40W). It also claims the current to be 80mA (but I measured it as 60mA, a rating of ~17VA ... not 8W at all, giving a power factor of 0.47). The actual generating capacity needed is therefore closer to ½ that of the 40W incandescent lamp, not ¼ as claimed. People are being seriously mislead by the term 'power' - as noted above, this may be what you pay for, but is not what must be generated."

This is wrong also. Any modern generator can provide significant reactive generating capability, even when working at full load. For example the 660MW units at Eraring power station can produce 410 MVAr of reactive power while generating 660MW of real power (more at lower load). The prime mover only needs to provide real power (not the reactive power), so no additional coal (and green house gas) is required above the real power drawn by the lamp.

In addition reactive plant is typically installed in switch yards close to the demand, avoiding reactive losses on the transmission lines. Transgrid has 3300MVAr of shunt capacitors installed on the Newcastle / Sydney / Wollongong 330kV and 132kV system.

An 8W lamp will require approx 8.6W generation capacity, versus 43W required for an incandescent lamp.

David

What about all that stuff he wrote about CLs not being reactive? How can the CL have "poor PF" and yet not be reactive? Forgive me but I'm just another ASD c*nt. ;-)

harmonics.

and passive PF correction works just fine - they are called harmonic traps (or filters). of course you wont fit any such passive harmonic/VAR compensating stuff inside a CFL.....

also, while var compensation is fairly common at the PCC of a large customer (eg steel mill), there is none for small customers (eg house). and there are a lot of houses.

so the VARs whizz back and forth, at least as far as the nearest substation (which probably has var compensation), heating up the line. the losses here are a thorough inconvenience, but the real problem is the heat - lines are designed for a given amount of heat. If thats coming from VARs (to whit: reactive current and line resistance), then it cant be used for W.

Cheers Terry

Oh, ok. I never really thought of that, but I never really think much about PF anyway. ;-) I guess I just always thought it was about inductive or capacitive reactance and that was it. I didn't really think of waveform distortion as anything more than line noise.

Kinda tough fitting those parts in the lamp base. ;-) Couldn't they just build them into fixtures or outlets, or do they have to be customized for the CFL at hand? Aren't they just low pass filters? Or is that only part of the problem and that you need to still apply correction for reactance?

Ok, got it.

This is the crux of what I referring to. For mass market CFL products the physical size of the components needed to make an effective passive VAR filter are too big and too expensive (relative to size and cost of CFL products). Active PFC is readily available for switch-mode supplies and small integrated PFC & regulator devices are in development (maybe even available now) for CFL and standard FL ballasts.

some (naughty) manufacturers specify unity displacement factor for their rectifier-capacitor input stages. which is true. but conveniently ignores the masses of harmonics.

rather than LPFs they tend to be selective traps. you would need a very, very high order filter to attenuate 3rd harmonic by, say 20dB while leaving 1st alone.....

and using 50/60Hz reactive components means they are LARGE.

Or is that only part

you can loosely categorise loads thusly:

1) resistive loads - unity power factor, no harmonics 2) reactive loads - non-unity power factor. if the loads arent too nonlinear (magnetics are, somewhat) then no harmonics. 3) non-linear loads. non-unity power factor, truckloads of harmonics.

the most common example is a rectifier-capacitor input stage for a smps. This draws a LOT of harmonics (eg 60% 3rd isnt uncommon), but typically the fundamental is pretty much in-phase with the voltage (the measure of

1st harmonic phase shift is called displacement factor, DF = cos(Phi1)), so the 1st harmonic looks resistive (AKA isnt reactive)

so if you snot the harmonics, the PF ends up pretty good.

A simple way to improve a rectifier-cap filter is to use two caps and 3 diodes, so the caps charge in series and discharge in parallel. Still nasty, just less so.

Cheers Terry

"Terry Given"

** There is no actual reactive component in the current draw.

No current can POSSIBLY flow back from a CFL into the supply.

Since EU regulations do NOT require a load of less than 75 watts to comply with PF or harmonic current regulations - the Chinese are not gonna make CFLs that do.

...... Phil

"Dave" ?????????? The IDIOT

** PFC ICs exist for CFL ballasts.

But as no regulation makes the Chinese use them, they wont.

....... Phil

hes actually right with about 70% for the most part, some being probabilistic, like turn on time and lifespan

*but*

his method of imparting these posts makes him look stupid therefore his posts might well have the opposite effect therefore he is prob a mouthpiece for big business...

The question arises then:-

Does he want to look stupid and undisciplined, was he not breast fed or what other reason could he have for being so agressive, does he need viagra or some other stimulants other than being compelled to swear on technical topics...

--
Regards
Mike
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http://niche.iinet.net.au

Haven't you seen the current waveforms on that site Phil mentioned, and understand the implications of CFLs pulling current only on the peaks of the mains voltage? Or am I remembering the theory wrongly....?

Bob

that may not be true. If there is an EMC filter on the AC line side, it will contain both DM & CM inductance. Hence DF will not be exactly one. The pi filter on the DC side may also look a bit inductive, depending on actual component values (if the bulk of the capacitance is on the rectifier side, it wont)

hmm, by definition AC always does that.

and thats really the crux of the issue.

I suspect that once incandescents are gone, the power generation/distribution industry will shriek, and loudly. relevant legislation wont be too far behind.

expect to see the same sorts of problems in apartment buildings that happened in office buildings when PCs with SMPS became ubiquitous - undersized neutral conductors failing (and even catching fire).

Cheers Terry

the chinese will make whatever is asked of them. We the consumer could immediately force the use of PFC CFLs, by refusing to buy non-PFC CFLs (and telling the supplier why we wont buy them). But of course we wont....consumers will buy whichever is cheapest.

I'm doing a PFC design for an electronic lamp now (not CFL). not for unity power factor (although its required), but for maximum efficiency ;)

Cheers Terry

" Terry Given KIWI PSYCHOPATH "

** What insane crap.

** But you still insist on seeing it from the WRONG point of view.

Fuckwit !!

...... Phil

It happened before SMPS were common. I helped install a mainframe computer in a large Canberra office building back in the mid 80s. When it was switched on the 3 phase star connected mains transformer started to smoke. After some investigation we found it was due to the excessive 3rd harmonics on the mains from the hundreds of fluros in the building (confirmed when the problem went away at 2am when the building lights went out).

The sparkie's solution - pull of the neutral connection and let it float. there was 80 volts between the mains neutral and the transformer star point after that was done. The machine ran like that for the next 6 years without any problem.

was it the flouro ballasts saturating that caused the excessive 3rd?

yikes! I can just see someone coming along, thinking "I can touch neutral, its connected to Earth" and getting an unpleasant, potentially fatal, surpirse.

Great story!

Cheers Terry