Active PFC & 115/230V switch

[jorwex]

A friend of mine recently bought a new powersupply and seems to know alot more than I do about them. I'm in the market for a new one and we were talking about the different features of new PSUs.

We were talking about active pfc and he said that powersupplies that have the feature do not have the 115/230 volt switch on the back--therefore the only features on the back should be the power cable, and the power switch.

I've come across a few apparent exceptions and wanna make sure that I wasnt misinformed. After abandoning trying to find a cheap modular psu, i've found the Thermaltake TR2 500w model, or W0093RU.

It says it has the "PFC function" on some spec sheets and does explicitly call it active pfc in others, but it has the 115/230 switch.

http://www.thermaltake.com/purepower/w009394TR2/w009394.htm

So what I'm asking is

(1) do active pfc PSUs definately have NO 115/230v switch
(2) does that Thermaltake PSU have active pfc

I came accross one that was labelled on newegg as having active pfc, but later found that it was only available on the internation version of the model, and not the one that was on newegg (and that had a switch on the non-international version).

Thanks

 

[Wentelteefje]

Normally, your friend is right... ThermalTake's site mentions two versions of the PSU, a W0093(RU) that has PFC, and a W0094 that hasn't... I have a PurePower 460W (with the blue led) and that one has an Active PFC... A bit of explanation:

Power Factor Correction (PFC)
Power Factor Correction (PFC) allows power distribution to operate at its maximum efficiency. There are two types of PFC, Active PFC and Passive PFC.

Active PFC
The preferable type of PFC is Active Power Factor Correction (Active PFC) since it provides more efficient power frequency. Because Active PFC uses a circuit to correct power factor, Active PFC is able to generate a theoretical power factor of over 95%. Active Power Factor Correction also markedly diminishes total harmonics, automatically corrects for AC input voltage, and is capable of a full range of input voltage. Since Active PFC is the more complex method of Power Factor Correction, it is more expensive to produce an Active PFC power supply.

Passive PFC
The most common type of PFC is Passive Power Factor Correction (Passive PFC). Passive PFC uses a capacitive filter at the AC input to correct poor power factor. Passive PFC may be affected when environmental vibration occurs. Passive PFC requires that the AC input voltage be set manually. Passive PFC also does not use the full energy potential of the AC line.

According to these statements, the PSU will have Passive PFC if there's still a switch on the backside of your power supply... Probably the W0093(RU) has the passive variant...

 

[Ike0069]

If it's true Active PFC, then a switch is not necessary since it capable of adjusting to the full range of voltages of 110-220.

But for whatever reason, some Active PFC models still have the switch. My guess is that maybe it means their Active PFC is not 1000% reliable. Not really sure about the reason for this.

Either way though, PFC (Active, Passive, or none) has no real effect on how the PSU performs, especially on 110V native. In Europe, PFC is required for PSU's, but that was brought on by the power generators vice the consumers.

Let me suggest that you go with a different brand PSU. TT is barely acceptable at the very best. A Fortron or Enermax would be a much better chooice IMO.

The 400W Enermax Liberty (modular with true Active PFC) is only $80 if you really want a modular PSU.

 

[ribbon13]

Enermax's mid-range models are definately no better than TT. Most of thier line is just as mediocre. The Liberties are an exception but they also cost more.

Best explanation of PFC is in my sig.

 

[Ike0069]

Originally posted by: ribbon13
Enermax's mid-range models are definately no better than TT. Most of thier line is just as mediocre. The Liberties are an exception but they also cost more.

Best explanation of PFC is in my sig.

Well, I'll take any Enermax model over the Antec's people whore on this board any day.

Besides, a solid 400W modular PSU for $80 is a great deal IMO.

 

[GalvanizedYankee]

Dan's Data is fun, but for something of this nature there are much better sources. I humbly offer one for your information and edification

http://www.xbitlabs.com/articles/other/display/psu-methodology_8.html

The whole article is worth the read, for those so inclined

Cliffs: Active PFC is good to have but not requiored. Passive PFC amounts to none at all or so close to it, you can't tell the difference.

Note: My Fortron and Zippy have active PFC. All ATX Zippys have active PFC, 90-264 VAC.


...Galvanized

 

[Zepper]

I think some PSUs w/ active PFC now have a split-range rather than a single, full-range voltage tolerance circuit. It saves a bit of money and works pretty much as well. I like the wide-range design as it helps make the PSU pretty insensitive to line-side garbage and even some brown-outs, but since most people are using decent surge protection and/or UPS these days, full-range will probably go the way of the dodo soon.

.bh.

 

[jorwex]

If a PSU doesnt say anything about PFC, does that mean that its passive, or just doesnt have it?

and if anyone has any suggestion for a powersupply for around 75 bucks, i'd be interested. I'm looking for one with two 12v rails, fairly stable rails, quiet (been looking at ones with 12 & 14cm fans), and possibly active pfc (gotta read all of these links now!). thanks for the replies

 

[Zepper]

If PFC isn't mentioned then (in most cases) it doesn't have it. You didn't mention what kind of system you are going to use it to power. We can't assume it's the one in your sig... Newegg has a couple of Zippys in the HG2 series at a good price right now. Some of the new Fortron/Sparkles are good buys and I always recommend the Sparkle FSP550-60PLG or the FSP550PLG-SLI for around $85. per Froogle. The new Silverstone Striders are good values too.

And don't put much truck in split +12 rails. Single rail of same total capacity is more flexible in a reasonable power rated PSU.

.bh.

 

[jorwex]

ive been looking at the antec truepower 2.0 550w. its at newegg for 75 after mail in rebate. i would like one 12v rail of the same capacity, but each has 19amps and a max combined of 34amps which is pretty high i'd say. ill check those out. it is actually the pc in my sig. my powersupply has been dying and ive ignored it. last i checked, there were brown burn marks on the floppy connectors. ive got 2 more harddrives in it, but otherwise its the same pc (and i removed the liteon dvdrom/cdrw). im moving it all into an antec superlanboy. thanks

 

[jorwex]

Alrighty, I've narrowed it down to

Antec Truepower 2.0 550 w @ $86 shipped or
Seasonic S12-430 430 w @ $82 shipped

the antec has more wattage, but lacks the active pfc, efficiency, build quality, and near silence of the seasonic

cant decide!! 430 watts doesnt seem like enough to me, and the antec is pretty quiet already...

any suggestions? i hate spending money

 

[jackschmittusa]

I have used Antecs in all of my personal rigs for quite some time now, and never had a complaint.

 

[Ike0069]

430W is plenty unless you plan to go SLI.

Go with the Seasonic!

 

[jorwex]

any more insight? do seasonics really have a better build quiality than the higher end antecs? does anyone know how quiet the truepower 2.0 550w is? silent pc review has the seasonic as one of their 2 recommended powersupplies, but they havent done any reviews on any of the truepower 2.0 PSUs. thanks

 

[Zepper]

The Seasonic S12 series is more efficient than most. If it has the power you need and still is in your price range, that would be on my short list.

.bh.

 

[jorwex]

ive got

dvd burner
3 ide harddrives
athlon 2500+
audigy 2zs
ati aiw 9800 pro

should i be worried about 430 watts? the 500w model is way more expensive. theres this site i found w/ froogle that has the seasonic 430 for only 76 on sale.

 

[Zepper]

I doubt that that system would hit 250 true watts very often.

.bh.

 

[jorwex]

really...i guess ill go for the seasonic

thanks!