Investigating AC Power quality

PSUs: The source of DC power for all components in the PC & often a big noise source.

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cloneman
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Investigating AC Power quality

Post by cloneman » Thu Jul 12, 2007 11:03 pm

I have a number of devices that have whining/buzzing coils. While it's no doubt the result of being on SPCR and being more tuned to these subtle sounds, I am begining to wonder weather the quality of the power my machines are getting should be brought into question.

I read something very interesting once comparing UPS systems, those that did regulation, cleaning, and a whole bunch of other fancy things with your power.

Could dirty power put stress on components that eventually leads them to become whiners? Is there any easy way to run a diagnostic on my outlets? Is it worth investing in some sort of device that improves the quality of power my stuff is getting?

Thanks....

N.B. most of my whining components are known to be whiners (Antec SmartPower PSUs, for instance) but I'd still like to know about what you guys think of improving power quality.

zistu
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Post by zistu » Fri Jul 13, 2007 2:41 am

I'm not sure about the power being the cause of the buzzing, but I can tell you what made me decide to invest in some power protection and power regulation hardware.

The place I live is a rented house, and ever since we moved in here I had noticed a strange thing with the power. If you'd use a vacuum cleaner somewhere in the house, you could see the lights dim for just a small period in the entire house when turning the cleaner on. Later on I found this to be the case with all heavy devices. I had it checked by some "expert" but he didn't find anything worth worrying about, which makes sense, since the landlord would have to fix the issue and turn up for the costs.

I decided this wasn't going to be very good for any hardware, so I went out and bought an APC Smart UPS 1000 and connected all my equipment to it hoping it would resolve the issue and protect my machines from the powersurges I noticed in the lights.

Later on I bought a laser printer. When I connect that and turn it on, the lights in my office blink (dim/normal) continuously while the machine starts and initializes. When printing something the same happens. The blinking annoyed me but connecting a laser printer to an UPS seemed kinda silly, since it has some very high power draw peaks. I asked UPC for a solution and they recommended me the Line-R 1200 VA. I connected the laser printer through that and the blinking is pretty much gone. I can hear the device switching sometimes when I turn on the printer or print pages.

Both devices run completely silent., with the exception of the situation when the power goes out. The UPS makes a buzzing noise then, with an alarm loud enough to wake half the block. The UPS has an array of status LEDs which can light a room at night.

I've been running this stuff for about 6 years now, and they seem to be doing their jobs. The UPS has a tool to graph the input power it receives and has a log where it records certain events. Over the years it has logged undervoltage situations on various occasions, and it once saved me some work because the power failed and it allowed me to shut down my machines gracefully.

The most common flaw with power outlets seems to be the grounding, or lack of grounding. In my years I messed with computers I more or less formed the idea that the absence of grounding can cause a greater risk of failure of equipment, based on some personal experiences and reading experiences from others on various forums. It's hard to prove this matters, but it makes sense in many ways. Grounding is required for UPS operation and surge protection devices, and some of them contain some form diagnostic, mostly in the form of a "Power Good" LED or something fancier specifically to check the grounding.

The only diagnostics I have done myself is to measure the voltage coming out of the outlets with a multimeter, since that is as far my toolbox and knowledge range. I've made one more or less interesting observation by doing so. My parents house is right near a transformer building. When I lived there I measured the voltage to be around 260 volts. I read up on this and it seems this is common. I once had the opportunity to measure the voltage futher down the block in the same street, and did notice it was lower there. So the distance related to the power distribution nodes seems to have some influence on it all as well.

In the recent years I have considered hiring an independent expert myself to look at my power situation, and to install grounding throughout the entire house (as is a standard building requirement these days here). But since I'd be improving a house that's not my own, I am waiting for some spare money to spend on it, and not sure when that time comes :)

As said I am not sure about the AC power being the source of your problems. I am not sure using an UPS or alike will solve your problems either. But in my situation it seems to have worked nicely in the time I have been using them. It solved some annoyances for me in the first place, and judging from the logged events it seems to have done some good in protecting my equipment as well. I've not had any buzzing hardware (except the UPS on battery mode), but I can't say I had any before I started using the equipment either.
I feel my investment paid off and I'd like to think my computers are happy with the power I feed them, but without me gaining the proper education and equipment, I am not sure I will ever be able to put my finger on hard facts supporting that feeling.

Hope this helps you some.

Bluefront
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Post by Bluefront » Fri Jul 13, 2007 3:07 am

zistu.....I tend to believe your "dimming/blinking" problem is caused by a general wiring problem, rather than a missing ground wire. Perhaps the guage of the wiring is too small, maybe there is aluminum wiring and/or outlet corrosion, or the service box and the wiring coming into the house cannot handle the current of new high amp devices. My own house was built around 1950, and had that same problem. To fix it, I had to install a new service box with upgraded wiring to the outside pole. Then I had to install several new outlets with new wiring to the service box. When I use high amp devices, I have to use these new outlets.

cloneman.....what you suggest may be worth a try. Places like Best Buy in the USA, sell many different sorts of line conditioning devices. Some of these things are costly.....look at the "Monster Power" brand for some ideas.

zistu
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Post by zistu » Fri Jul 13, 2007 3:37 am

Bluefront wrote:zistu.....I tend to believe your "dimming/blinking" problem is caused by a general wiring problem, rather than a missing ground wire. Perhaps the guage of the wiring is too small, maybe there is aluminum wiring and/or outlet corrosion, or the service box and the wiring coming into the house cannot handle the current of new high amp devices.
You're right, I mentioned the grounding problem more as a common issue unrelated from mine, or that was my intention :) I am thinking of having a professional install a new service box and redoing the wiring, but like said have not had the proper motivation to do so yet. My computers are all connected to a wire which runs directly to the service box. I installed that because the room I have my computers in did not have grounding. This has me convinced it is something in the service box or whatever leads up to that. I don't trust myself enough to mess with the service box, and everything leading up to that is beyond my jurisdiction - messing with that will get me disconnected and / or fined :oops:

Thanks for your reply, it gives me some more hope I can actually solve this problem some day.

cloneman
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Post by cloneman » Fri Jul 13, 2007 7:02 am

Thanks for the replies :)

P.S. the lights do go dim in my house when I plug some high power unit in, like a hairdryer, or heavy duty power tool. I always thought that was pretty normal, heh.

peteamer
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Post by peteamer » Fri Jul 13, 2007 9:55 am

cloneman wrote:P.S. the lights do go dim in my house when I plug some high power unit in,
Krell used to design their audio power amplifiers to deliberately do this, to perpetuate the myth of them being incredibley powerfull... and therefore proving the virility and sexual prowess of the owner..... (I kid you not. )

Yes there is a link between 'The Krell' on 'The Forbidden Planet' (remember the 'unlimited power' thing) and the company name,..... :wink:

kittle
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Post by kittle » Fri Jul 13, 2007 12:59 pm

petamer - were the krell amps the ones you could arc-weld with? ... not that i would try that.. but i know one place kinda advertised it.


Ive always been a fan of proper power protection on PCs since a voltage spike in college toasted a PC i was working on for somebody.

This may be different now, but I beleive a UPS will also act as a power filter to smooth out the hiccups and annoyances in powerlines.

My apartment has some lousy wireing too -- i could hear my subwoofer go thump whenever the fridge turned on, so i invested in some good quality surge protectors and line conditioners, and the problem went away.

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