Sign in with
Sign up | Sign in
Your question
Closed

Eletromagnetic Emissions of Power Supplies - Safe enough?

Last response: in Components
Share
November 12, 2005 7:38:31 PM

Hi all,

I know that this could be a strange topic for people, but I have big suspects that my 550W power supply from Antec is emitting a high grade of electromagnetic emissions not safe for me.

I got an Antec Model: TRUE550PEC three years ago (approx), cataloged as the best power supply in its category at that point. (by Tomshardware too).

Firstly all, take in consideration that I spent in front of PC more and less from 14 to 16 hours a day.

By other hand, take in consideration that is not easy to explain this issue with exact words, above all if english is not my natural language. Well ...

One year ago (approx), in a daily basis, an sometimes twice a day, I feel something as a "pulsing wave" in the environment of my room, and I cannot support it and have to go out of my room until I feel that it ends (less than a minute or so). My head feels this as a momentary pulsing pressure. After that, my ears buzz for a long time, (no strong but as a backgrounding and constanting beep)

I have reviewed all components of my PC, disabling and updating all funs to bigger funs, avoiding small fans with a lot of revolutions (another common source of electromagnetic emissions).

All my system is spending approx. 140w. I afraid I purchased an excessively strong power supply that needs liberate some internal charge time to time. I did it to get a stable PC. I have an UPS system by MGE (Merlin Gering), valued at US$350, so I think that current is provided very stable to PC.

The BIG question is that when I do not work on my station (a whole system valued at US$4,000), and of course this system is turned off. Everything is OK!!!, so certainly there is a component in the system that is emitting this.

I am a professional of computers for 18 years, and more than 30,000 hours of fly-hours over Internet since October 1996, so please, for anybody that think that this issue sounds as a sci-fi story, or the message from an paranoid person, or have not idea about what I am speaking, do not reply or post stupid things about this issue.

I appreciate any opinion from somebody with electronic/electrical engineering knowledge. The basic question are:

- if powerful power supplies need to liberate condensed energy in some form and in determinate moments, and therefore I am feeling this due to my prologued work in front the system.

- and the most important thing, if above thing is true, then ... Could I solve this issue purchasing other safer power supply

- What power supply? One less powerful? More modern technology? The money is not a problem. This one had cost in 2002: US$190. I could purchase one valued at US1,000 if I could solve the issue. Anything to work in a safe way.

To do mention that this post is a serious matter.

I will appreciate so much some opinion from Tomshardware staff, and I hope this thread could be valid for a new trend in Tomshardware reviews taking in consideration the ergonomy of computer components in terms of health for users. For example, the electromagnetic pollution that a system emits, because as you know, all electrical components have some kind of electromagnetic emission. The big problem is the level and intensity of this.

Thank you very much in advance.

Mapg

BTW:

You can read about Power Supplies as EMI emitters at ...
http://www.devicelink.com/mem/archive/05/10/007.html

_____________________________________

Conclusion:

A system's power supply is often the primary source of unwanted electromagnetic emissions. When EMI is a concern, it is crucial that device manufacturers select a power supply that meets all applicable EMC standards to minimize issues when integrating the power supply into a system. Interference can occur to a power supply as well, so it is also critical that the functional performance of the power supply is acceptable. Certain techniques can minimize EMI in a power supply. These include the following:

- Selection of transformer core.
- Transformer winding and shielding.
- Component layout and loop size.
- Use of X and Y capacitors.
- Use of CM and DM chokes.

For optimal EMI control at the OEM system level, it is imperative to ensure that all of these points have been considered when selecting an ac/dc switching power supply.
Anonymous
a b ) Power supply
November 13, 2005 6:39:42 AM

I am not a doctor but do have some insight to power supply architecture and EMI issues.

Depending on where you live and bought your supply it is likely that it conforms by law to some government mandated emissions requirements. I am pretty sure that Antec sells the same equipment rebadged appropriately to all of it's customers worldwide and won't have an electrically loud version it ships to lawless 3rd world countries (even if there is such a thing). This is how most companies do business for financial reasons. It is guaranteed that a known power supply manufacturer like Antec will be making parts that are bombarding you with less radiated energy than is legally in the airwaves around you from other radio sources when working properly. By this I mean things like radio stations CB operators and cell phone signals etc.

Typically the supplies I've seen are CE EN 55022 class B rated if I am remembering right. This is a European standard for consumer IT products and is fairly strict. By strict I mean very little radiated energy in the tested ranges (30M-1000MHz). The reason they all get this rating is it is the strictest standard in the world for this class of equipment. If equipment meets this standard it can be sold anywhere.

A practical analysis of the situation will allow me to say: it is extremely unlikely to be a radiated EM wave problem, the physics of it simply minimize the possibility to nearly zero probability. Audio frequencies just won't radiate efficiently off any antenna you can fit into your computer room. It is many magnitudes higher probability that it would be a conducted problem at the frequencies you mention to get the sensation you mention, ie a short circuit through your ear or head.

It may be possible that your power supply isn't functioning properly for whatever reason and is no longer conforming to whatever standard badged on it's sticker and is radiating alot. If this were the case I still can't imagine any mechanisms built into your body which would allow these very high frequency EM emission profiles to be realized as an audible signal in your head. For example your body just isn't laid out as useable radio (AM,FM etc.) antenna/tuner.

Now I am going to make a really uneducated shot in the dark and say: It sounds to me like you could be suffering from poor blood circulation issues. :?: :?: :?:
November 13, 2005 6:43:25 AM

Pulsing wave in your head? That's interesting.

Since you spend 14-16 hours a day in front of a PC maybe this is stress related. How is your health? Blood pressure?
Related resources
November 13, 2005 9:38:18 AM

Firstly all, thank you for your replies.

I have though all these things you commented, but certainly I have a good health (thanks to God of course) and the problem goes out when PC is off.

About the feeling in my body. Well, as I commented, is complex to explain with exact words. It's like a "momentary" and pulsing sensation of load in the environment that press in my ears and head, so in that moment, I prefer to go out from the room and immediately, while I go far from PC, the sensation is progressively less until finish (when I am far enough). If I return quickly I feel that pressure in the environment again, so I wait some time (1 minute or so approximately).

About to hear or feel radio waves and so on, well, of course I am not a superman with a hidden power.

I have read information in several sources about electromagnetic pollution and its influence is people. The worst thing is that all these things are not enough researched yet, and even unknown the real consequences in the long-term about the exposure to electromagnetic radiation from electronic consumers products. (Above all, nowadays with this high requirement of energy from computers that are requesting more and more resources).

Maybe my power supply is damaged in some way (despite it was or is a great model) or simply not and the prologued sitting (for months) near to my computer is the real cause. A non-enough tested effect over the health is certainly possible since researchers cannot conclude about electromagnetic influence on humans in the long-term.

I was reviewing high-end models of PSUs like Seasonic S12 600W (the best of the best today), but my worry is if this kind of high products with so strong electronic components could provide the same effect in the long-term, (seeing what is haping now).

The money is not a problem, the problem is to recognize if there is a real influence of high-powered electronic products to cause these kind of issues and therefore, to choose other kind of components.

I even thought to build a low-powered Micro-ATX PC (as Tomshardware recommended for some cases) with a Pentium-M 735-780 (35W) with an all-in-one motherboard for 479-M (like AOpen i915GMm or MSI 915GM) and finish all this.

I do not know yet. But believe me. I had never been posting something like that if I hadn't known what I am speaking about. I work with computers since 1987, purchasing and mounting only the best components in its category to work finely and safety.

I would invite to Tomshardware team to take in consideration some kind of different perspective about ergonomy beyond the simple numbers provided by manufacturers. That is the real favor to users and consumers.

Regards, and thank you for your replies again.

Mapg

BTW: Recommended reading as a first approach ... (non-technical problematic exposition of course)

Are Computers Hazardous to your Health?

Electromagnetic Fields and Radiation
http://www.uft.org/member/publications/health/computer_...
Anonymous
a b ) Power supply
November 13, 2005 8:08:28 PM

Interesting article. The article seemed to express the most concern about the low frequency EM fields. I was half joking about when I mentioned the short circuit through your head or ears, but it seems this is where the author is most concerned.

Obviously a well designed PC will have very little in the way of stray electric fields, but the author is right in that there will certainly be stray magnetic fields all over due to all of the current flowing everywhere. The best way to protect yourself from magnetic fields is with high Iron content shielding, and or physical seperation with distance. As an example steel cases are great for blocking magnetic fields. Aluminum will do very little magnetic field blocking. Power supply fan holes are where the fields will be the strongest on a steel cased PC. Staying away from the back of the PC where the fan hole is located seems like good advice.

As mentioned the high voltage flyback transformers found in CRT monitors are definitely a potential source of strong magnetic fields. LCD screen monitors eliminate this problem nearly completely. Maybe you could try one of those and see if your symptoms decrease.

To reduce the worry about low frequency conducted problems get yourself a steel computer case, stay away from the back of it and try an LCD monitor. For whatever reason I homed in on the radiated energy problem rather than the conducted problem in my first reply. It actually does make more sense that conducted (ie induced current or force in your head due to sitting in some E or M field) would be more likely to cause your symptoms since it can be be present in very close proximity, especially by a cathode ray tube monitor. Also these magnetic fields can exist in the audio range but again only in close proximity.
November 13, 2005 11:23:03 PM

Seeing is believing.

I am really happy because I found the problem, and certainly was a complex issue, and you will see why.

As first affirmation, yes I was right: Power Supplies can produce an abnormal amount of radiation, but taking in consideration some conditions "out of the responsibility" (refutable affirmation for sure) of the Power Supply itself. Because of this I said: Seeing is Believing.

As I mentioned I have a MGE UPS (Merlin Gering) of 1000VA (specifically an Ellipse Premium model), and a 17' CRT Samsung SyncMaster 757DFX (working at 1152x864 pixels at 100Hz).

Well. Since I purchased this UPS 9 months ago, I see that control software of the unit is having a strange behavior in an important parameter: The remaining time of autonomy. Instead of mark a constant level of battery autonomy, has peaks of 28 minutes but 7 minutes too in a random order.

This is a bad thing, because if current is down in the house, and this parameter is on 7 minutes at that point, the UPS will try to close and turn off the PC, and certainly I did not purchase an expensive UPS valued at US$350 to rely on just 7 minutes of autonomy.

Well. I researched this issue for a long time, and realized that when I plug the monitor out of UPS to the usual current intakes at home, this parameter of UPS goes fine and always marks 28 minutes (the maximum time I could work with the current down), namely, everything goes back to normal.

I called to MGE support service and they sent me another Ellipse Premium 1000VA. The problem continued. I explained them about the monitor issue because support service was believing that this matter was caused by a communication problem between UPS and PC, because of this the wrong reading about the battery autonomy.

But not, the real culprit is the monitor because as I mentioned when I unplug it from the UPS, all readings are OK.

What I never realized is "what monitor was doing to UPS and to me through the Power Supply"!!

Some days ago, I was reading the manual of my motherboard and I saw there are two special certifications for UPS compatibility that my GigaByte GA-8INXP is in conformity:

- EN 50091-1: General and Safety requirements for uninterruptible power systems (UPS)

and ...

- EN 50091-2: EMC requirements for uninterruptible power systems (UPS)

Then I though ... If my Samsung CRT Monitor is not in total conformity with these two certifications?

Taking in consideration the problems I had when plugin the monitor directly to the UPS, this idea about the certification issue couldn't be wrong. I guessed.

I did the test and unplugged the monitor from the UPS and plugged it directly to an usual current intake. As I mentioned, the parameters reading of battery autonomy were OK, but the most important thing: The sensation of load in the environment was disappearing and later, I realized that the pulsing wave I mentioned in previous post went out. (I do mention of this because this kind of pulsing wave wasn't there all time, of course).

Believe in me, I have lived for months with that sensation of load in the environment for many hours (14-16 a day), and I can promise you that when I unplugged the monitor from UPS things changed quickly.

Now. My conclusion, and I think this is the most interesting part, because above reasonings are an introduction to the issue.

I do not know if the certification compliant is real or not for the Samsung monitor (anyway it turned on a light in my mind about causes), but what is absolutely true is that my monitor is causing a bad functioning of the UPS.

How I connect all this to the power supply radiation?

I think (to summarize the problem) that, due to some kind of interference, induction or similar things caused by the connected monitor in the electrical part I guess, UPS was not providing the right current to the power supply, so trying to keep a stable AC/DC conversion and voltages for the PC, the power supply was working really really forced and emitting some kind of radiation. I guess that electromagnetic radiation as usual in electrical/electronic components.

As I mentioned, this is a complex issue where several elements produce an bad effect each other and resulting of this, I had to suffer all this bargain for a long time.

By other hand, I didn't do mention of this before because I was a bit shamed to mention it, but when I went to sleep, I felt like sparks in my head (like flashes) for some minutes (not very intensively but they were there). Today don't. Realize how worried I was for awhile.

And what I ask myself. Imagine that twenty years later I suffer some illness due to this. Who was the culprit? Antec as Power Supply manufacturer? Samsung as Monitor producer? or MGE as UPS maker?

Who? For sure nobody! Everyone will hide its head. Bad luck guy! They could say me.

Well, I hope all this was a interesting reading to realize about some serious issues about computers and heath. An interesting reading with a victim of course: ME!

Best Regards,

Mapg
November 13, 2005 11:27:32 PM

*stares blankly at screen, drooling, and scratching head*
November 13, 2005 11:55:35 PM

As you know, I mentioned in previous posts a suggestion for Tomshardware staff about a change of perspective in its policy about ergonomy. Well, here you have the first example ...

For the intensive check to power supplies you did one month ago: To measure the EMI radiation or any non-safe emission at full load.

Because maybe, I repeat, maybe (ironically) some power supply could produce an unbearable stay in the workshop if somebody stays several hours there. It's not just a question about... I plug the power supply and I go out quickly! (funny but true thing). No way, measure that!

This is what I was referring about a new perspective to serve one of the most valued treasure of consumers. "The health".

Everybody entrusts in certifications provided by manufacturers, of course. That's OK. but,... Is it a professional position to blindly entrust in "absolutely all" what they say/write in the papers? Are manufacturers absolutely all time trying to avoid non-safe effects? or trying to get money?

Who is the culprit?:

1.- Antec because permits that a UPS gives a bad current flow to its power supply instead of reboot the system and warning user about something goes bad?

2.- MGE UPS because doesn't warn that a component (the CRT Monitor) is injecting some kind of interferences and causing a bad functioning.

3.- Samsung because doesn't check rightly what its monitors could be causing to UPSs

These are the real questions.

Mapg
Anonymous
a b ) Power supply
November 14, 2005 3:08:13 AM

Shoot, I didn't notice that in your first post you had mentioned having the UPS in the system. This whole time I was thinking you meant the Antec when you were referring to your power supply. My bad.

The problem with less costly UPS's is that they don't produce a true sine wave output, but use what is called a modified sine wave output. It wouldn't be the first time I have heard of equipment struggling to function properly on this type of dirty power. These modified sine wave output UPS's put out what I will describe as a stair stepped equivalent representation of a sine wave. A CRT monitor uses a transformer, the flyback transformer I mentioned earlier, as part of its high voltage supply. The physical properties of a transformer allow it to work well at one frequency but reject higher frequencies from passing. The CRT transformer is likely tuned for 50 or 60 Hz and will not work well at other frequencies that are much away from these. These stair stepped sine waves actually contain many harmonics at much higher frequencies than the fundamental (50/60Hz), this is the problem.

There are very expensive UPS's available which put out a true sine wave which alleviates this type of equipment clashing. The true sine wave output UPS's do not contain the high frequency harmonics but only the fundamentals. This means the power is efficiently coupled through the flyback transformer and not rejected.

You have a couple of options here:

1. find another monitor that deals well with the UPS you have.
2. Get a UPS that your existing monitor works well with.

I would likely be looking at option 1 for cost reasons. I would again suggest an LCD for your consideration. I assume there are CRT's you could find which would work better than what you have, but for the reasons I mentioned they will always be less than optimal with a modified sine wave output UPS. Due to the extreme change in architecture, ie no more high voltage supply and thus no flyback transformer, I suspect going to an LCD is the safest bet for success.

When I say option 2 is more costly I mean by quite a bit. Just try looking at a few true sine wave output UPS's in the VA range you are considering and see what I mean. I will take an uneducated guess around $1000-$1500 for what you need.

I am glad you are starting to troubleshoot to narrow down what this problem is. When I first read your post lets just say I was shocked at what I was reading but now it is all starting to make more sense to me. Very interesting.
November 14, 2005 3:10:08 AM

Whoa, i tryed to read it all but when i realized that it was THAT long and only 6 posts i gave up.

Did you read it all? if so can you give me a 50 words or less about it? the title makes me curious
November 14, 2005 3:15:38 AM

I don't understand what's going on. I just am here to offer my incredibly good looks as support for the ladies.
November 14, 2005 3:19:36 AM

I am just here to stalk you and provide a distracting avatar....
Anonymous
a b ) Power supply
November 14, 2005 3:44:40 AM

Cool now everyone can see how beautiful I am too.
November 14, 2005 3:51:45 PM

Hi

Thank you for your reply Knewton. I understand the problem, but I would like to clarify my ideas about some of you told:
Quote:
The physical properties of a transformer allow it to work well at one frequency but reject higher frequencies from passing.


Then CRT Monitor is not receiving the right current from UPS due to this UPS's simulated wave?

Quote:
The CRT transformer is likely tuned for 50 or 60 Hz and will not work well at other frequencies that are much away from these. These stair stepped sine waves actually contain many harmonics at much higher frequencies than the fundamental (50/60Hz), this is the problem.


How things "go back badly to the UPS" too and I guess that later, they are forwaded to Antec Power Supply? If this is the correct flow of the problem.

Is because CRT rejects the badly formed current provided by UPS with so many harmonics on higher frequencies? or is because UPS rejects Monitor current requirements?

I understand you in a "grosso modo" way, but please,... Can you describe some kind of flow to recognize the paths, because I do not understand at all how this war (UPS-Monitor) arrives to the Antect Power Supply. I guess that could be because UPS "becomes mad" providing a current to Monitor that is rejected by this Monitor, but I am not sure, and then the consequences of all this arrives to the Antec Power Supply.

Do you think that my Antec Power Supply could be damaged too by this war for so long time between Monitor and UPS?

Seems to work rightly now but I could purchase another one (i.e: a Seasonic S12 600W) even if in appearance my Antec is right but in some kind of hidden function not.

About the monitor. Well I am designer, and I have to design in accordance with the people will see, because of this (for many people today) my "poor?" 17' CRT Monitor.

But this is another kind of subject, and is not suitable to cover it here right now. No problem to get a LCD EIZO or Iiyama 21'. but the professional design field is another land, different from the user-end level.

Best Regards. Happy to solve this serious issue and hear from you, Knewton. Thank you for all.

Mapg
Anonymous
a b ) Power supply
November 14, 2005 6:59:35 PM

First of all I would just like to remind you that I am making best guesses based on what you have told me and I have understood. With respect to the guesses as to what is happening nothing is guaranteed and to guarantee would take having the equipment in front of me in my test lab.

With that in mind....

Quote:
Then CRT Monitor is not receiving the right current from UPS due to this UPS's simulated wave?


UPS's are actually modelled as voltage output supplies. And yes I am guessing that at least part of your problem comes from the non sinusoidal aspects of the UPS output signal.

Quote:
Is because CRT rejects the badly formed current provided by UPS with so many harmonics on higher frequencies? or is because UPS rejects Monitor current requirements?


If my guess is correct then the monitors power supply rejecting the stairstepped voltage put out by the UPS causes the monitors high voltage supply to behave in strange ways. And yes this could result in a strange current draw profile.

Quote:
I do not understand at all how this war (UPS-Monitor) arrives to the Antect Power Supply.


It may be that the Antec supply is perfectly happy and operating just fine with this type of power. In fact it seems as you may have already found evidence that points that way. The testing where you had only the PC hooked to the UPS and the monitor on mains power and the symptoms were gone would suggest theAntec is doing OK. I say go with what seems to be working.
November 14, 2005 10:58:41 PM

Thank you very much for your reply.

Finally I have some conclusions in accordance with my current evidences:

1.- UPS and CPU run OK without Monitor connected to UPS.
Isn't it sad? To purchase an expensive UPS to get that?

2.- Monitor cannot be connected to UPS because ...

2.1.- UPS is not able to measure battery autonomy rightly. (a consequence of the war UPS vs Monitor)
2.2.- Monitor doesn't receive the right voltage needed.
(About above point. Even I can see a light flick in the screen when CRT is plugged to UPS, despite I work at 100Hz).

3.- Power Supply works fine, and does not emits some kind of pressing radiation.

4.- Pulsing wave is emitted by UPS (this is the new proven evidence).
4.1.- When Monitor is connected, this feeling of pulsing wave-load in the environment is more frequent, intensive and prolonged. I have even to leave room.
4.2.- When Monitor is not plugged, this kind of condensed energy that is liberated in form of a pulsing wave, is emitted time to time and less intensively. I have not to leave the room but I feel it.

Then I have to decide several things about this $350's MGE UPS:

1.- or to throw this beast out of home.
2.- and/or to consult to some consumer association to denounce this rubbish and to MGE
3.- or to live with this less intensive peak of radiation emitted less frequently.
4.- or to purchase a $1000-$1500 UPS for a simple PC System as any mortal human has at home.
5.- or to purchase another brand of UPS like APC, and check if works (maybe money for nothing again)
6.- or to disconnect CPU from UPS and pray that my system survives for a long time.

Now, I even do not entrust if this rubbish is safe at all with a prolonged near stay.

Well, I will reflect on what I could do. Any idea is welcome.

Thanks for all

Mapg
Anonymous
a b ) Power supply
November 15, 2005 1:13:48 AM

regarding your option 5.

Quote:
5.- or to purchase another brand of UPS like APC, and check if works (maybe money for nothing again)


Just make sure it is of the true sine wave output type and you should be fine if what I have been saying is correct. I have been looking around and I have seen a couple by Tripp Lite and APC at around 1000VA for under $500 US. Maybe my $1000-1500 estimates were a bit out of hand.

A good true sine wave output UPS would probably be the best route if you can afford it because then your existing components should work with it and you don't need to worry about buying something that won't work together again.

Whatever you decide to do let this reply to this thread and let us know how it works out.
Anonymous
a b ) Power supply
November 15, 2005 1:16:04 AM

BTW I did some research and see that all of the soho MGE UPS's I found are indeed the modified sine wave type, ie the bad kind. So it could very likely be what ails you.
November 15, 2005 8:47:40 AM

Hi KNewton,

As almost everyone who purchases electronic consumer products, we have no a consolidated idea about so specific electronic terminology, because of this, when I go to take a look at APC.com site, the reading of so many terms unknown for me makes me mad.

It is not necessary to purchase an UPS with 1000VA, I can rely on less autonomy, 500VA or 800VA. I do mention of this because it is difficult to endure the idea to count with an useless $350's MGE UPS at home, that I cannot connect due to a superlative lack of professionalism from MGE engineering team (polite way to avoid insult them) to prevent collateral effects of UPS functioning over users health at the Soho market (60-70% of the total market).

Finally to do mention that currently, this is not just a question of changing from a simulated wave to a true wave, and purchasing another UPS class, but if these kind of products rely on some electronic components that could produce these emissions. Solenoids, condensers, etc., not perfectly isolated/shielded that are accumulating energy and have to be liberated in some determined moment. Sorry, I do not know the electronic terminology at all.

This is the most important thing for me now taking in consideration what I suffered past 9 months and also, unknowing if all this has produced some effect in my health in the middle-long term. Realize that I even had to leave the room when emissions were produced. Isn't this sad and evident?

As almost everyone here, I cannot isolate a UPS in a basement or far from me, above all because USB cable to manage UPS features is 1.5 meters long. (Irony: MGE should provide a cable with 1000 meters and a health insurance).

I should be obligated with you KNewton if you could provide me some kind of link to Apc.com or information to search a true wave UPS, and distinguish it from products with a simulated wave. I should weight up if to pay another UPS or to call MGE and initiate a true war with them because I am starting to wish it and unmask this irresponsible form of manufacturing.

Thanks a lot and I hope that Tomshardware could take some initiative to measure the safety of PC components in the near future.

Best regards,

Mapg

BTW:

As you can see below, nobody should entrust at all then in "words over the paper" from manufacturers while the producing cost is in the middle of the path. (money is money).

Taken from http://www.minutemanups.com/support/pwr_un10.htm

Quote:
Sinewave vs Simulated Sinwave - Which is Best?

A sinewave output is the optimum waveform for electronic equipment. The incoming AC line is a sinewave, thus electronic equipment expects to see this type of waveform. A sinewave is the most expensive output form for UPS manufacturers to produce due to more complex circuitry and components. [...]

A pulse width modulated squarewave (also called simulated sinewave) is considerably easier to produce in a UPS. This type of waveform is quite suitable for virtually all electronic business equipment. [...]
Anonymous
a b ) Power supply
November 15, 2005 1:42:12 PM

go here to get into APC's websites
http://www.apcc.com/
It seems their desktop stuff is all modified sine wave. You need to look at the server quality gear to get into the true sine wave ouput grade of equipment.

I would suggest calling MGE's application support line and even APC's apps group as well. I am confident that everything I have written is more or less true and you could pull in some of the concepts from this post to use as ammo in your fight with MGE if you feel the need. However I would just warn you that they may take the stance that the consumer should beware as modified sine wave equipment is very common and is only a problem when it doesn't work. In other words it was up to you to understand what you were buying. As the article you found points out is the low cost solution and is fine for most cases.

I don't really know where to find information about this type of thing besided electronics text books. The problems that modified sine wave UPS's only really start making sense after looking at some high end electronics math for a while.
November 15, 2005 3:58:34 PM

Thank you for you reply and your time. I will take in consideration all possibilities.

I have taken a look at MGE and APC and you are right. All desktop products are based on this simulated wave. Do not worry I will research and ask about this issue to MGE technical team or APC. I do not want to waste your time more.

Pleasant to rely on your support and ideas about this issue.

Best Regards and thank you again. Good luck for everybody!

Mapg
July 9, 2009 7:43:40 AM

dude buy a new power supply, why risk damaging your hardware or yourself for that matter, 600w's are under 100$ nowadays and if antec didnt work out for you try another brand, typical shelf life especially when under heavy use (10-15 hours a day or 24/7) is 1-3 years, if its rocked for more then 3 be lucky and move on... maybe even get a new system......the antec modulars are nice.... the pc power and cooling are also a good choice.....if your computer doesnt even need 550w grab something cheaper... acepower and coolermaster are decent for there buck.... my 2 cents....
a c 144 ) Power supply
July 9, 2009 8:13:07 AM

Any computer power supply would not be susceptible to the effects of a simulated ac voltage from a UPS. The first thing, after the input filters, that happens is that the ac is turned directly to dc. It does not do through any transformers first.
July 9, 2009 8:23:39 AM

owen420 said:
typical shelf life especially when under heavy use (10-15 hours a day or 24/7) is 1-3 years

Well in that case the OP is screwed regardless, since he posted this back in 2005.
July 9, 2009 8:23:55 AM

This topic has been closed by Randomizer
!