Fake PFC Made of Cement - Page 1
Forum section: electronics / general

author: quantumfall
author_rank: Regular Contributor
timestamp: April 19, 2012, 08:11:20 am
content: I know some PC PSUs are built to a price but this is crazyhttp://www.hardwaresecrets.com/blog/Hantol-PSU-Fake-PFC-Made-of-cement/220

author: nanofrog
author_rank: Super Contributor
timestamp: April 19, 2012, 08:28:19 am
content: Reminds me over-sized metal cans over undersized transformers, where the empty space was filled with sand or something to make buyers believe there was a hefty PSU section (early '80's IIRC).

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: April 19, 2012, 09:17:18 am
content: ThisFake Dell PSUhad a bunch of metal strips to add weight.

author: quantumfall
author_rank: Regular Contributor
timestamp: April 19, 2012, 09:42:15 am
content: You have to wonder why we have any standards at all when this crap gets into the market.

author: saturation
author_rank: Super Contributor
timestamp: April 19, 2012, 11:07:26 am
content: Although other countries counterfeit, China has taken it to new highs. Good photo from transformers or coils in SMPS, found in the OP links:

author: G7PSK
author_rank: Super Contributor
timestamp: April 19, 2012, 11:54:33 am
content: Wonder how much they save by making a coil with all those lamination's and then making the winding's from cardboard cant be much the labor is about the same or even more the amount of copper is not that much and coils do not need to be copper many are made of aluminium, it can only be cents on each unit, and one certainly does not want jail time in China.

author: firewalker
author_rank: Super Contributor
timestamp: April 19, 2012, 12:00:15 pm
content: You can buy/steal/recycle rejected part from factories and use them in such a way.Alexander.

author: quantumfall
author_rank: Regular Contributor
timestamp: April 19, 2012, 01:19:49 pm
content: We do it with politics and finance

author: AlphZeta
author_rank: Regular Contributor
timestamp: April 19, 2012, 01:27:05 pm
content: Wow, I am speechless...In general, I don't have problems with products that cut corners to save cost---as long as they don't try to hide anything. But this really got you wonder how far they can push....

author: quantumfall
author_rank: Regular Contributor
timestamp: April 19, 2012, 01:39:42 pm
content: It would be interesting to know how much of this there is. If its in the 1KW PSU for $35 stuff its buyer beware, common sense.Its when it gets in the critical stuff we need to really worry.

author: AntiProtonBoy
author_rank: Frequent Contributor
timestamp: April 19, 2012, 03:12:03 pm
content: It's funny and infuriating at the same time. Feel sorry for the poor bastards, that get sucked in by this.

author: Rufus
author_rank: Super Contributor
timestamp: April 19, 2012, 03:19:35 pm
content: Quote from: AlphZeta on April 19, 2012, 01:27:05 pmChinese mentality. It looks OK and still works, not quite as well as it should, but, this design improvement doubles our profit margin and we think it would be quite unreasonable for you not to accept it.

author: nanofrog
author_rank: Super Contributor
timestamp: April 19, 2012, 11:43:42 pm
content: Quote from: AlphZeta on April 19, 2012, 01:27:05 pmProblem is, most doing this sort of crap do seem to do their very best to hide it.

author: M. András
author_rank: Super Contributor
timestamp: April 20, 2012, 08:10:50 am
content: i can imagine the R&D cost of these fake stuffs

author: Pentium100
author_rank: Frequent Contributor
timestamp: April 20, 2012, 08:38:47 am
content: PFC in a PC power supply does not really matter, though if the PFC coil is fake, the rest of the power supply is most likely not very good either.

author: T4P
author_rank: Super Contributor
timestamp: April 20, 2012, 10:38:13 am
content: Quote from: Pentium100 on April 20, 2012, 08:38:47 amActually nowadays as power supplies get bigger but remain ATX size , they need more efficiency , to avoid big heatsinks and a massively loud fan at the same time .Like i have seen actual 95% in decent supplies . but yeah PFC does matter and if it is fake , no doubt about the capsactually 1000W is a nominal figure seen in power supplies nowadays and at 95% 1000W is of course 50watts heat .And now 1500W supplies are getting mainstream and as they get closer to the max 110V power of 16amps(i think) they need to keep it down( And by the way , what is the max current you lovely folks from the states getting at the plug ? )

author: AlphZeta
author_rank: Regular Contributor
timestamp: April 20, 2012, 12:40:05 pm
content: QuoteIf I remember correctly, building codes dictate the maximum allowed current for the home 120 outlet to be 20Amp.

author: ejeffrey
author_rank: Super Contributor
timestamp: April 20, 2012, 12:57:05 pm
content: Quote from: AlphZeta on April 20, 2012, 12:40:05 pmIt depends on the wiring. 12 gauge copper for 20 amps, 14 gauge for 15 amps. Most new installations are 20 amps, but there is still a lot of 15 amp wiring out there. The outlets are the same in either case, and always rated for 20 amps, but the fuses/circuit breakers have to be chosen to match the wire gauge.

author: rsjsouza
author_rank: Super Contributor
timestamp: April 20, 2012, 01:11:22 pm
content: Here in the US the wiring varies on the age of the house. Mine has 15A breakers.Back in Brazil the standard also mandates 15A for regular outlets, but depending on the region of the country the system is either 110V or 220V (single phase, 60Hz) - thus different classes of power.

author: T4P
author_rank: Super Contributor
timestamp: April 20, 2012, 01:21:45 pm
content: I see , thanks , no wonder power supplies that are designed for the entire world is limited to 1650VA power draw .

author: siliconmix
author_rank: Frequent Contributor
timestamp: April 20, 2012, 09:09:27 pm
content: Quote from: mikeselectricstuff on April 19, 2012, 09:17:18 amyou could work a few hf amateur bands with that tx

author: PStevenson
author_rank: Regular Contributor
timestamp: April 20, 2012, 09:45:16 pm
content: I've given up being annoyed by that stuff, now I just find it funny - I however feel the need to take my computer apart and check.

author: mariush
author_rank: Super Contributor
timestamp: April 20, 2012, 09:58:52 pm
content: Romania .... here as far as I remember, the wall sockets are 230v 10A, the power strips are pretty much the same.I wouldn't trust the wires inside the walls to carry that much in older houses though.The Americans with their puny 110v... I feel sorry for them.

author: RJSC
author_rank: Regular Contributor
timestamp: April 20, 2012, 10:50:09 pm
content: Portugal 230V @ 16A (3.68 kW) maximum per outlet , but the code allows up to 8 outlets on the same 16 amp circuit, so, if you draw 16A on one outlet, you cant draw anything else on the remaining outlets who share the same breaker.It a pitty though that most houses only have a 15A contract... The power company circuit beaker always flips before the individual circuit brakers do.Here we have to pay monthly for what they call "Available Power" even if you don't use a single kWh! It's insane!Then off course, on top of that Availability Tariff you pay per kWh used.Here is the table:Power Price (Month)1.15 kVA 2.29€2.3 kVA 4.03€3.45 kVA 5.33€4.6 kVA 6.92€5.75 kVA 8.50€6.9 kVA 10.09€10.35 kVA 14.85€13.8 kVA 19.60€17.25 kVA 24.36€20.7 kVA 29.12€What other countries use this "available power" billing scheme?

author: slateraptor
author_rank: Frequent Contributor
timestamp: April 21, 2012, 03:05:08 am
content: Quote from: mariush on April 20, 2012, 09:58:52 pmWhere's Romania again? Oh, that's right...

author: Mechatrommer
author_rank: Super Contributor
timestamp: April 21, 2012, 04:00:21 am
content: Quote from: mariush on April 20, 2012, 09:58:52 pmi bet you havent get in close contact with your 240V mains. or watch how the spot welding machine works.btw: here at the edge of the world, you can occasionally see villages burnt to the grass because they dont follow regulation. not that crappy 15 or 20A or whatever regulation. they just dont install circuit breaker into their home, think its too much expensive. yes, its expensive... it cost a village.

author: IanB
author_rank: Super Contributor
timestamp: April 21, 2012, 04:27:18 am
content: Quote from: ejeffrey on April 20, 2012, 12:57:05 pmActually the outlets are different. Standard outlets are for 15 A and there is a different design with pins in a T arrangement for 20 A. You may certainly find 12 gauge cable and 20 A breakers behind 15 A sockets, but this is because you can have several sockets on one circuit and you can make up a total of 20 A by plugging in several loads on different sockets.See picture for what 15 A and 20 A plugs and sockets look like. Most homes do not have any 20 A sockets though.

author: mariush
author_rank: Super Contributor
timestamp: April 21, 2012, 12:22:27 pm
content: Quote from: Mechatrommer on April 21, 2012, 04:00:21 amI actually was, about 2 times, and a third time I accidentally shorted a socket with a voltage detector which got thrown out of my hands all the way to the other side of the room. You learn fast to be careful and respect electricity.Still wouldn't trade the 220-240v for 110-120v, there are much more advantages to it.... and I had a second look... the circuits and the fuses in the panel are 16 amps ... just the individual sockets and the power strips I have are rated for 230v 10 amps.QuoteYeah, I can understand that and it sucks.When I was a student living in a campus, in the first years before they installed a custom water heating system in each building, the 4 story building I was in had lousy heating through the winter, so some people used to have large ceramic bricks with thick coils in them as heaters... 1500-2500 watts wasted as heat.You can imagine those things, plus a fridge, plus 2-4 computers in a room on a 230v 16a circuits... fuses would pop. So the solution was to simply use NAILS in the manual fuses... and about once every 2 weeks the main fuse for the whole floor (about 30 rooms) would pop.We also had old style network with those round plugs and terminators... what a load of fun that was to search each room on the floor to see which socket had broken ground contact or who removed the terminator from the end of the cable... and feel the 80v or so going through you when you try to unscrew the plug from the back of the pc... but that's another story.

author: ejeffrey
author_rank: Super Contributor
timestamp: April 21, 2012, 12:55:25 pm
content: Quote from: IanB on April 21, 2012, 04:27:18 amThat may be officially true, but it doesn't reflect common practice. In home and commercial installations NEMA 5-20 plugs are unheard of and 5-20 sockets are uncommon and mostly only common in old installations. Actually, I think I have seen more 1-20 (ungrounded) sockets than their grounded counterparts, I guess because the distinction was only common before grounded outlets were required for all indoor use. I don't think I have ever seen a device with a NEMA 5-20 plug. They may exist in some industrial or medical environments, but they are not in general use. Certainly if you go buy a 2 kW device like a high power hair dryer or an electric kettle they still have the standard "15 amp" plug. The socket is rated for 20 amps in either case, the purpose of the keying was only to prevent you from plugging 20 amp appliances into 15 amp wiring.

author: IanB
author_rank: Super Contributor
timestamp: April 21, 2012, 05:33:07 pm
content: Quote from: ejeffrey on April 21, 2012, 12:55:25 pmIndeed I did say you don't generally see 5-20 sockets in homes, but the hardware store is full of them so there must be a demand for retrofitting.The NEMA 5-15 sockets are only officially rated for 15 A as you can see from the picture.I don't know that I have seen a device that comes with a 20 A plug, but also I have not come across a 2 kW device designed for 120 V. The highest power devices I have are rated 1800 W and these are fitted with a normal 15 A plug (since 1800 W / 120 V = 15 A). I imagine that devices fitted with 20 A plugs would not be very popular as people would get them home and wonder where the heck they were supposed to plug them in

author: wkb
author_rank: Super Contributor
timestamp: April 21, 2012, 05:52:14 pm
content: Quote from: RJSC on April 20, 2012, 10:50:09 pmThe Netherlands do. And it is quite a logical scheme if you look at it. Wouldn't you go for the max power version ifit didn't cost you a penny extra? And what would that mean for the overall infrastructure required? And what would that cost?

author: G7PSK
author_rank: Super Contributor
timestamp: April 21, 2012, 07:03:15 pm
content: All the company fuses have seen in the UK are 100 amps.

author: Pentium100
author_rank: Frequent Contributor
timestamp: April 21, 2012, 09:12:59 pm
content: Quote from: Dave.S on April 20, 2012, 10:38:13 amBut does PFC increase the efficiency of the power supply itself? I mean it's an extra circuit that makes the input current be sine instead of whatever-you-want-to-call-it when it's just a rectifier and a cap, so it may actually reduce the efficiency (no component is ideal). I always thought that PFC was mandated by law (for power supplies bigger than 75W or so) so that the apparent power (and thus the strain on the distribution network) is reduced, not because of efficiency - the home user pays only for real power, so it doesn't matter that the current is out of phase with the voltage or just not a sine.

author: rsjsouza
author_rank: Super Contributor
timestamp: April 22, 2012, 01:39:35 am
content: Quote from: Pentium100 on April 21, 2012, 09:12:59 pmActually no. As you said, being an additional circuit that obeys the laws of physics (and therefore requires energy to operate), a power supply with PFC will always increase the amount of power required. You will be doing the same amount of work (i.e., powering your PC), but this time with a nicer sinewave input...Especially in the PC arena, what gets confusing is that the recent 80 Plus initiative means the PSUs have >=80% efficiency (a side requirement is to have a PFC of 0.9). The third paragraph of the article below talks about that (although in a very confusing way in my opinion):http://www.cooperindustries.com/content/dam/public/bussmann/Electronics/Resources/Brochures/Power_Factor_Correction_(PFC)_Application_Notes.pdfSeveral articles are around, but one I found particularly amusing to read is below:http://www.dansdata.com/gz028.htm

author: T4P
author_rank: Super Contributor
timestamp: April 22, 2012, 02:21:42 am
content: Active PFC is getting standard and it is a important thing.This coolermaster 460W model has like 86% in the middle ( as with all SMPS )http://www.coolermaster.com.sg/product.php?product_id=5483Same goes for this 1300W , 92% efficiency at 220V .http://www.coolermaster.com.sg/product.php?product_id=6732

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 22, 2012, 03:04:09 am
content: Quote from: rsjsouza on April 22, 2012, 01:39:35 amEvery power supply with active PFC I have worked on always became more efficient if the PFC was "bypassed" by adding a cap across the output of the bridge rectifier or (for 120V input) reworking the rectifier into a voltage doubler. The efficiency loss is especially significant with 120V input due to higher current. Residential customers are not billed by power factor so PFC at home does no good for most applications. The few exceptions are if the PFC is also being used to vary the DC bus voltage (some motor drives, battery chargers, and audio amplifiers) or if the power supply is large enough to push the limits of a 15A circuit.Even then, it comes at the cost of higher complexity as well as more things to go wrong. (In college, professor Dr. Ehsani told a story about one of his students accidentally disconnecting the feedback of a PFC front end while it was running, which destroyed the board in a very exciting way.) If you saw the lab power supply teardown, notice that it has no PFC at all even though it's definitely intended for industrial use.

author: Pentium100
author_rank: Frequent Contributor
timestamp: April 22, 2012, 06:52:55 am
content: Quote from: NiHaoMike on April 22, 2012, 03:04:09 amSo, as I said, a fake PFC is not necessarily bad for the customer, but if the manufacturer put in fake PFC, then the rest of the power supply won't be high quality either (also probably with non-existent overload and other protections).

author: rsjsouza
author_rank: Super Contributor
timestamp: April 22, 2012, 10:50:23 pm
content: Quote from: NiHaoMike on April 22, 2012, 03:04:09 amRe-reading my post I am not sure if I was clear, but I also agree with the fact that a PSU with PFC is less efficient.Quote from: NiHaoMike on April 22, 2012, 03:04:09 amThat comes with the trade; we can't stop things to get more complex. However, we need to be smart in desiging things that make the most to avoid the fireworks spectacle (although I love to see things blow).I also agree that correcting the power factor is a very important thing, as mentioned by Dave S. My biggest pet peeve is that marketers say that 80 plus PSUs are more efficientbecausethey have a PFC of 0.9, but that is a fallacy. Design the PSU with 85-90%+ of efficiency then put the PFC to bring it back to ~80%.Quote from: Pentium100 on April 22, 2012, 06:52:55 amTotally agree. I've taken apart several reputable, non-reputable and "supposed to be" reputable brands of PC power supplies to discover a great correlation of the two. Can't say anything about industrial PSUs, though.

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 22, 2012, 11:31:19 pm
content: Quote from: rsjsouza on April 22, 2012, 10:50:23 pmPFC is indeed important for business use where the customer is charged for power factor or if you're trying to squeeze more watts out of the outlet (or both), but residential customers are not charged for power factor and very few home electronics draw enough power for PFC to make a difference.