Poor quality power in building

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I've had a bit of an epiphany lately, and it's that my previous apartment building might have had some really poor quality power. It was a high-rise built in the 1970s with 16 floors. Below is a list of strange electronic/computer problems I had in the two years I lived there:


1. Ground loop hum from high-end JBL monitors
Eventually remedied it with a ground loop isolator, but ferrite caps and different power strips/outlets did nothing.

2. Blown caps in one of the aforementioned JBL monitors
One speaker would intermittently hiss and squeal, sometimes very loudly. Was serviced under warranty and several capacitors were replaced. These speakers have two amplifiers each (tweeter + woofer).

3. Computer power supply causing weird POST errors on motherboard
The same Thermaltake PSU + eVGA mobo combo worked perfectly for a year in the previous apartment, then I moved to this place and within a year it would randomly refuse to POST or have strange freezing problems. RMA'd the PSU and the problem went away.

4. Same motherboard started having weird POST errors again
Replaced the Thermaltake PSU with a high-end Corsair unit and the problem went away for about 6 months.

5. Same motherboard had different POST problems
Similar issue but different symptoms. All PSU pins tested fine and voltages were well within spec and very consistent. Motherboard was out of warranty so I decided to just replace it with the latest and greatest. This new mobo had 8-phase PWM and was one of the highest rated/most-awarded ever (Asus Z87-A).

6. New motherboard and PSU has sporadic POST problems
Same issue as before, even though the Asus mobo was a totally different design and manufacturer. Intermittently would not POST and indicated a CPU fault, but flipping the switch on the PSU or hitting reset repeatedly seemed to correct it. Found small percentage of people complaining of this problem with my particular PSU + mobo combination. Same issue happened even when I moved to my current place, but less often. RMA'd the Corsair PSU and got a brand new one.

7. USB DAC developed very strange hiss with certain USB cables
I use an Audinst HUD-MX1 external DAC on my computer and it developed a very strange hiss shortly after I moved in that you could only hear if the USB cable was actually UNPLUGGED, but only from the computer (not from the DAC itself). I never had this issue before.

8. Two different power strips randomly indicated "wiring fault"
The power strips I use have an LED that says you have a wiring problem in your building. In different rooms, on different circuits, they would randomly flash this light on for a few days then it would mysteriously go away.

9. Every 6 months, the building would lose one phase of power
ComEd would inevitably come out to fix it, but during that time I would see bizarre behavior from my electronics. The speakers I mentioned above would power on but didn't produce any sound, for example.

10. Certain light bulbs needed replacing every 6 months
In particular, the 50/100/150 3-way bulbs in two of my lamps on different circuits could barely make it 6 months before needing replacement.



So am I totally crazy here, or did my previous apartment clearly have power problems? It seemed really weird that so many of my electronics had bizarre problems I could never really pinpoint ever since I moved in there. Even brand new stuff developed odd problems very quickly.

I've only been in my new apartment for a week and a half, but all of the above problems I listed are totally absent.

Somewhat OT, new view from my family room:

1941311_10102852772413112_5915565491950331450_o.jpg
 
Yeah, sure sounds like it to me. BTW, built in the 70s...did they use Al wire in apartment buildings?
 
Originally Posted By: zrxkawboy
Yeah, sure sounds like it to me. BTW, built in the 70s...did they use Al wire in apartment buildings?



Dunno. How could I have tested that without ripping things up?


Logic and previously living with an electrical engineer seem to say that power supplies should have cleaned up the [censored] input power (that's their primary job after all), but perhaps it was just too much for them to deal with on a constant basis. My computer and the speakers were running almost 24/7 and those were the most problematic.
 
Something like a CyberPower CP1500AVRLCD should give you a count of overvoltage, undervoltage events, and it's reasonably priced.
 
Need to use a UPS with a power conditioner and check for aluminum wiring....
 
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Originally Posted By: spackard
Something like a CyberPower CP1500AVRLCD should give you a count of overvoltage, undervoltage events, and it's reasonably priced.


thumbsup2.gif
We've got one for our 55-inch Vizio TV and computer.
 
Consumer grade UPSes and line conditioners are a joke. We had a good discussion on it here once before to prove that, and I have friends who are EEs that said they're effectively worthless unless you have an industrial grade one and use highly-sensitive instruments.

The whole point of a power supply is that it filters out garbage and cleans up the power before it hits the actual electronics. So, in a way, a power supply IS a line conditioner.
 
The question is whether the problem is in the power supply to the building, or a problem with the equipment/wiring in the building itself.

If it is dirty power being supplied, a relatively cheap way to clean it up is to install your own transformer between the supplied power and the building.

But I suspect the problem is actually something haywire in the building......Probably lot of things haywire. I would start with getting someone with the correct equipment doing a thermal survey of all the power panels in the building. Not cheap, but a whole lot less expensive than a fire. Just sayin'.
 
We get some weird stuff in our buildings, with over and under voltage in some legs of 110V. Usually its a photocopier that keeps having issues that gets the investigation going. Desktop computers though don't seem to care much at all though.
 
Originally Posted By: dparm
Consumer grade UPSes and line conditioners are a joke. We had a good discussion on it here once before to prove that, and I have friends who are EEs that said they're effectively worthless unless you have an industrial grade one and use highly-sensitive instruments.

You still might be able to see some benefits, at least with respect to a few devices. When I lived in a rural area some years back, the power was terrible. Components started to fail in my computer. I couldn't keep light bulbs in the place. I did go to a UPS, and at least it kept the computer on a somewhat even keel. Obviously, my light bulbs never saw an improved lifespan.
wink.gif
At the time, they even marketed light bulbs for rural areas with more flaky power, believe it or not.

My big issue wasn't just with the power being dirty or poor quality, but far too frequent big dips in voltage. I think that's about the only thing the UPS really helped with.
 
Originally Posted By: dparm
Consumer grade UPSes and line conditioners are a joke. We had a good discussion on it here once before to prove that, and I have friends who are EEs that said they're effectively worthless unless you have an industrial grade one and use highly-sensitive instruments.

The whole point of a power supply is that it filters out garbage and cleans up the power before it hits the actual electronics. So, in a way, a power supply IS a line conditioner.
Traditional Audio power supplies are very rudimentary, many withwout chokes, and amp output is sensitive to line condition + noise. Computer supplies shold be more robust and have low ripple and noise.
If you have a triac ( or other high power switched supply in uses) somewhere taking a notch out of the line, you will know it through really flakey operation on many devices. At Work, I had my room of parts-handling Seiko robots go crazy (when a laser cutter was running in the next room- which I didn't know at the time) After much hair pulling, Finally Scope'd the line with a tech and it had a 50v notch for 10% or the period missing. NAsty! The modern world is noisier still. IS there data xfer allowed on the neutral leg yet?
 
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to OP:

Your power line issue is multifaucet'ed: noisy coupled with dips/spikes and so on.

If you live close to industrial area, you'll get these kinds of problems from large motors from industrial side.

The only true way to determine how "bad" your situation is is to find some tech (or your experienced EE friend) to scope the line over a period of time and watch for spikes, dips, EMI/RFI related noise, etc. and then take it from there.

If the situation is beyond your handling/managing, perhaps consider moving to another (assuming power is cleaner there) location?

Q.
 
Originally Posted By: Quest

If the situation is beyond your handling/managing, perhaps consider moving to another (assuming power is cleaner there) location?



I already did move, as I stated. It was just an interesting conclusion I drew.

As to the earlier comment about PSUs being rudimentary, none of my audio equipment is low-end or even really consumer-grade. My speakers are JBL Pro monitors designed for studio use. They're not really built to the lowest possible price...they are built for performance.
 
Originally Posted By: dparm
As to the earlier comment about PSUs being rudimentary, none of my audio equipment is low-end or even really consumer-grade. My speakers are JBL Pro monitors designed for studio use. They're not really built to the lowest possible price...they are built for performance.

Yep, if it were me, I'd probably worry about that stuff the most. Back when I lived in a more rural setting, the computer was likely the most sensitive of all my electronics. The rest was limited to a CRT TV, a VCR, and a rather pedestrian CD changer.
wink.gif
 
It was aggravating even though most of this stuff was covered under warranty. Had to keep ripping apart the computer or spending the time to troubleshoot it. I don't buy low-end parts and that's because I know they are problematic. My PSUs have all been 80 Bronze or Silver, the motherboards have high-end capacitors and PWM, and so on. My new mobo, an ASRock Z97 Extreme4, has high-end alloy chokes, Nichicon 12k platinum caps, 12-phase all-digital PWM, next-gen dual-stacked MOSFETs, for example.
 
Have read about a flywheel UPS that uses a "shore power" motor to spin a huge flywheel that then spins a generator head to power your sensitive stuff. Secondary devices (batteries, gas motors) can keep the head spun up, or I suppose an inverter could handle the change in frequency as the flywheel slows down.
 
Originally Posted By: Garak
Originally Posted By: dparm
As to the earlier comment about PSUs being rudimentary, none of my audio equipment is low-end or even really consumer-grade. My speakers are JBL Pro monitors designed for studio use. They're not really built to the lowest possible price...they are built for performance.

Yep, if it were me, I'd probably worry about that stuff the most. Back when I lived in a more rural setting, the computer was likely the most sensitive of all my electronics. The rest was limited to a CRT TV, a VCR, and a rather pedestrian CD changer.
wink.gif



Yeah, me too.

In the good old days, you had a physically separate linear power supply that had filtering at the input, a transformer to step up or down, filtering at the output of the rectifier, and maybe active regulation ( that isn't an additional noise source ) and more filtering on the outputs, depending on what it is powering.

The modern trend to make stuff light and cheap doesn't really appeal to me. When I build something, the power supply always uses a transformer - I don't care what it costs or weighs, and the power supply is usually on a separate chassis.

Decent transformers are becoming harder to source these days, at least at the hobbyist level.
 
Originally Posted By: dparm
It was aggravating even though most of this stuff was covered under warranty. Had to keep ripping apart the computer or spending the time to troubleshoot it. I don't buy low-end parts and that's because I know they are problematic. My PSUs have all been 80 Bronze or Silver, the motherboards have high-end capacitors and PWM, and so on. My new mobo, an ASRock Z97 Extreme4, has high-end alloy chokes, Nichicon 12k platinum caps, 12-phase all-digital PWM, next-gen dual-stacked MOSFETs, for example.


Can't help you with your JBL monitor part but here's a thought (if you can find a cheap way to do so, so much the better*)

(1) get a 1:1 line isolation transformer (I have 2 of them from salvage, both are OneAC hospital grade) and then plug the output part to serve your PC(PSU) and monitor and see how that goes.

Rationale: these 1:1 line isolation suppose to be able to further isolate the most sensitive medical grade equipment from sudden voltage spikes and/or dips...as for line-borne EMI/RFI point of view, not so much.


This will help quite a bit if my "hunch" is correct.

(2) for line-borne EMI/RFI issues (suspect that you may also have some of such issue as well), you may have to experiment a bit from most consumer-grade products readily available.

Q.

example: (I have 2 of these @ home on standby (or whenever I need to do experimentation on):

http://www.ebay.com/itm/OneAC-One-AC-Vol...=item3ce26fa269

1kV type isolation transformer (some calls them Power Conditioner)
 
What you need for that is a power quality analyzer, like the Fluke 43B. I had the opportunity to use one of these to make some measurements years ago. Many 1000's of $$$$.

One experiment I performed was to measure in-rush current on an old Dewalt radial-arm saw wired for 110VAC. I measured 100A. I suggested to my friend that he really should rewire the motor for 220VAC!

You can easily view the AC waveform with a step-down transformer and an oscilloscope....if you know what you're doing. But you really need a FFT (fast Fourier transform) analysis to measure THD (total harmonic distorsion) and see the distorsion orders (1st, 2nd, 3rd, etc).

The 43B does all of this and you can hold it in your hand!
 
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