Re: Antec SL450P Smart Power Exploded!
Let me tell you this (probably a stupid counter-example, but anyways)...
I have lived a big portion of my life in Eastern Europe in one of those old concrete apt. complexes. As far as I know, our apartment building still has the same 3-phase motor that it always had - at least since the early 90's, that is (and that's only because someone stole the original motor). Now the entrances next to us still have their original elevator motors - back from when the condo complex was built in the late 50s.
And even with the cheap crappy power supplies of the late 90's and early 2000's (when APFC was still unheard of, and a 300W gutless PSU was just as good as a 300W brand-name PSU... except there were no brand-name PSUs to be found where I lived), I haven't heard of people replacing their elevator motors just because of "bad harmonics from non-APFC PSUs". Heck, the condo complex next door had a "game cafe" in one of the apartments. You know... the type with many computers crammed into every room of the apartment, and all of the computers built in the cheapest bottom-of-the-barrel cases and PSUs. And that's not the only place I knew that was like that. Many game cafes were the same way. No scratch that... many still ARE this way.
Most of the "damaging" harmonics you are talking about probably don't even make it past the first step-down transformer in the grid.
Right... that's why those old tube TVs and monitors are still working and so damn hard to kill. Come over to where I live now and see for yourself. People are dumping these large TVs on Craigslist for free... and all of them are working too.
Exactly! Which is why I suggested to goodpsusearch to just gut it and go on without it.
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In fact, let's have us all a bit of an educated discussion why APFC is so "popular" now.
- First off, it mimics a resitive load more or less, so better for the power company.
- Second, it allows a PSU to be a "universal" type without needing a selector voltage switch. It will also allow the PSU to function down to very low line voltages (especially in countreis with 220/230/240 V AC).
- Third, it allows same energy to be store on the "input" stage of the PSU with smaller caps.... Because remember, the energy stored in a capacitor is directly proportional to its capacitance and directly proportional to the square of the voltage across the capacitor. So by increasing the voltage just a little bit, you can lower the capacitance a lot. A single 330 uF 450V cap charged to 420V will hold the same energy as a pair of 1000 uF 200V capacitors in series charged to 340V total. Yes, you do have the complexity of APFC, like an extra MOSFET, diode, and torroid, but it does have the advantages mentioned above (as far as for who, that's another story). This last point especially applies to very high-wattage PSUs, where the extra capacitance can become prohibitively large (and very demanding on the NTC thermistor and other input components before it). So for those, it just makes sense to have APFC.
Let me tell you this (probably a stupid counter-example, but anyways)...
I have lived a big portion of my life in Eastern Europe in one of those old concrete apt. complexes. As far as I know, our apartment building still has the same 3-phase motor that it always had - at least since the early 90's, that is (and that's only because someone stole the original motor). Now the entrances next to us still have their original elevator motors - back from when the condo complex was built in the late 50s.
And even with the cheap crappy power supplies of the late 90's and early 2000's (when APFC was still unheard of, and a 300W gutless PSU was just as good as a 300W brand-name PSU... except there were no brand-name PSUs to be found where I lived), I haven't heard of people replacing their elevator motors just because of "bad harmonics from non-APFC PSUs". Heck, the condo complex next door had a "game cafe" in one of the apartments. You know... the type with many computers crammed into every room of the apartment, and all of the computers built in the cheapest bottom-of-the-barrel cases and PSUs. And that's not the only place I knew that was like that. Many game cafes were the same way. No scratch that... many still ARE this way.
Most of the "damaging" harmonics you are talking about probably don't even make it past the first step-down transformer in the grid.
Right... that's why those old tube TVs and monitors are still working and so damn hard to kill. Come over to where I live now and see for yourself. People are dumping these large TVs on Craigslist for free... and all of them are working too.
Originally posted by kc8adu
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In fact, let's have us all a bit of an educated discussion why APFC is so "popular" now.
- First off, it mimics a resitive load more or less, so better for the power company.
- Second, it allows a PSU to be a "universal" type without needing a selector voltage switch. It will also allow the PSU to function down to very low line voltages (especially in countreis with 220/230/240 V AC).
- Third, it allows same energy to be store on the "input" stage of the PSU with smaller caps.... Because remember, the energy stored in a capacitor is directly proportional to its capacitance and directly proportional to the square of the voltage across the capacitor. So by increasing the voltage just a little bit, you can lower the capacitance a lot. A single 330 uF 450V cap charged to 420V will hold the same energy as a pair of 1000 uF 200V capacitors in series charged to 340V total. Yes, you do have the complexity of APFC, like an extra MOSFET, diode, and torroid, but it does have the advantages mentioned above (as far as for who, that's another story). This last point especially applies to very high-wattage PSUs, where the extra capacitance can become prohibitively large (and very demanding on the NTC thermistor and other input components before it). So for those, it just makes sense to have APFC.
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. Pretty cool, though the way you balanced it with the two caps. I wonder why the Panny is reading low on capacity.
. It was probably tough for my parents, though. Basically the early 90's crysis in Bulgaria (and also Romania).
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