Let's Take a Trip Inside A Power Strip!

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I have a hard time imagining how a lamp could be "responsible" for busting a TV tuner except maybe in some sort of Rube Golbergesque chain reaction.

The lamp is connected directly across live and neutral. Under normal operation, no current flows through ground so the lack of ground on your lamp makes no difference. But turning off the lamp does cause a load transient on the UPS so maybe something happened there, somehow rippled all the way to your tuner and zapped it.

Depending on where and how your coax is grounded, it is quite possible the surge that actually zapped your tuner came from elsewhere... like a ground potential difference between mains ground and coax ground.
 
Great article! I wanted to suggest Tom's do reviews on APC's and power bars. I want to get an APC but I want one with a thermal fuse that's of great quality. I have a FirePro W9100 to protect :s
 


 
I mean that it trips the tuner to the other tuner. This transient change is not noticed until the first tuner is needed and unavailable. Windows Media Center can be set to optimize for WMC use, which may help with using the web or playing solitaire causing the same problem. The switch of the lamp problem is reproducible with instantaneous response but may be dependent on the system stability. The power for the tuners was also from the same UPS. The USB problem is a significant one for TV tuners so I also disabled power down but that failed to help the system at the time. I don't know if automatic changes in CPU speed have a similar effect.
 
You may wish to start a thread about your TV card issues.

I know cards like the HD PVR use a trick to work with Media Center. If they power cycle for any reason(quick power out), it will not be available to media center any more. You can restart the Hauppauge Media Center service to get it back. This is much faster than trying to restart everything.

I actually have that card on an older XS1200 ups from APC(non sine wave, but the device does not seem to have any issues with it). This ensures I do not have to make sure the HD PVR never looses power.
 
I am a design engineer, and I noticed that the voltage spacing was way too small! They slotted the boards so they could get away from PCB creepage distances. Interesting. At least if you did have a bad voltage spike, the close slotted areas would flash over and crowbar the line - not letting the surge through to your stuff. But you might have a fire then!
 
Thank you for this article, although I still detest the slideshow format. I would love to know what APC has to say in response to your mail. Please let us know if you are able (legally, etc.).

Also, while this specific model of APC power tap has not yet been part of a US safety recall, as far as I am aware, about 15 million APC units sold from January 1993 through December 2002 are:
http://www.cpsc.gov/en/Recalls/2014/Schneider-Electric-Recalls-APC-Surge-Protectors/
This recall affected at least three APC units I owned, and while of course even the most well respected brands can have issues, it is quite unnerving to hear that a supposedly high-end power tap is prone to melting and catching fire.
 

As noted in my page about the blown traces, I think that is exactly what they intended that for: MOVs short the major surge to ground/neutral, blow the live trace and the arc switches to the ground island to relieve the MOVs if the surge is really that bad. Since you need about 1kV/mm to strike an arc through air and the MOVs themselves (20D471K) start conducting around 385V, the MOVs (or the traces connecting them) have to fail first before voltage can flash over.

If a surge is bad enough to blow the trace and cause the bar to catch on fire, imagine what it would have done to a device hat was not designed specifically to handle that sort of event.


No response from APC yet.

The slideshow format is not that bad but the narrow text area can be somewhat irritating. As someone else suggested, you could view the "print" version instead - the option is on the bar off to the left. I had never thought of doing that before but if you want to read and see the whole thing without having to tab through images, it is a nice alternative.
 


 
If I can get organized I'll post something. Your mention of sine wave is an issue I had postponed since it also involves power supplies.
The main attraction of the USB Hauppauge 2650 is the remote for live TV and programming. The SiliconDust HomeRun Prime (separate computer) is Ethernet based and has also had issues with recording some channels mostly blank for some periods. These issues are discussed on GreenButton forums but no definitive answer is found.
Since WMC can lock up when both tuners are lost the Hauppauge Service is an option but it still can require knowing it needs to be used again. Thanks for the responses and your article.
 
Got a response from APC this morning: they will be sending me one of their newer models for review in the near-future and are also planning to comment on my story.

Look forward to that in the coming weeks!
 
Great article! I am too surprised by the quality issues with that particular unit. As others have stated it could be just a bad batch at the time. I too be interested in knowing the build quality of the older units out in the field via flea markets. At work in our server room we use high end APC UPS and they all work flawlessly. Most of them are over 5 years old. At home I use the CyberPower UPS as I like the brand and their prices are reasonable, especially their pure sinewave line. I haven't taken one of these units apart to see the build quality but so far no complaints.

Keep up the great reporting!
 
My new APC power bar went through a night of lightning storms this past winter that eventually knocked out the power over great areas. It never shut the power off
even though the indoor lights were flickering and dimming - until whole system went down for 3 days due to broken power lines..
 
"Got a response from APC this morning: they will be sending me one of their newer models for review in the near-future and are also planning to comment on my story.

Look forward to that in the coming weeks! "

Yeah, well our family bought 5 of these surge arrest power strips and my guess is that they do nothing at all to protect the appliances.
 
Why not make it a better review than being set up with their selection ?
Ask them to send you a coupon so that you can buy one, rather than being set up with one that they've selected.
 


If they don't, APC has a $100,000 warranty on their devices.
 
Do you think my power bar should have broken off power to the appliances when the room lights looked like it was an alien landing zone, on off on off on off ?

That's why I think it does absolutely nothing.

 
I picked up one for my brother when I was at the store and we were so impressed by the design, he bought a bunch and gave us two.

My experience is only with junk power bars and none of them turned off,ever.
Maybe I'm not understanding how electricity works, but I thought that the breaker should cut off power in that kind of situation.
 

A surge-suppression power bar or even a panel-mount central surge suppressor does not turn power off when power is unstable; it attempts to prevent major spikes from going through by shorting them across live to ground, live to neutral and neutral to ground.

It will only cut power if some sort of catastrophic failure or overload occurs downstream, including within the bar itself or in case of a really huge surge that might blow up those sacrificial traces I mentioned in the repair slides.
 
It seems to me that it might be worthwhile taking a look at the innards of some more of these. This doesn't give me any warm fuzzies about APC. What happened to pride in one's products?
Click to expand...

Yes indeed!
How are other brands doing? Wouldn't surprise if they were of similar (or maybe even worse) quality. What is the difference between an expensive APC unit and a cheap no-name product and is it worthwhile paying for?
This is one of those products that is hardly ever opened and/or tested, printing paper and cables alike.
=
 
I too have some APC UPS units, although my PCs are all on Cyberpower APFC units because of the much better waveform; even my hypersensitive SG-650 is happy with those (it will cut out on an APC UPS).
Click to expand...
I use a pfc Cyberpower UPS as well, I had an APS but it didn't play nice with my pfc power supply.

A teardown of a cyberpower UPS would be interesting if you're able to do so.
 
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