A strange buzzing sound coming from the PSU when using the No Break battery

[Ghostsoui]

I have a GX II 750w and now each day or each two days I have a poweroutage and is getting into my nerves so I bought a UPS no break and I only wanted around 10 minutes or less to at least turn off the PC..

One of my friend told me that this was good and it was enough for what I wanted and I bought a 1000 va 500w no break, model 10017 from koblenz, it works nicely for what I want but I noticed that when the computer is running with the backup battery the PSU makes a buzzing sound, I was wondering If this can damage my PSU in the long run, theres something bad with it?

 

[Solandri]

From a quick Google search, the GX II 750Watt is a Bronze 80+ high-efficiency power supply. You really should connect high-efficiency power supplies to a UPS with simulated sine output. They get a lot of their efficiency from closely following the sine wave form of the AC power they receive.

When you plug them into a cheaper UPS which usually produces something closer to a sawtooth or truncated sawtooth output, it can cause the buzzing sound you're hearing and can damage the power supply over time.

From your UPS brand, I'm guessing you're in Mexico. If you can get access to U.S. mail-order stores, these simulated sine wave UPSes frequently go on sale. Unfortunately, you just missed a sale on a 800 Watt simulated sine wave UPS ($98). The only one I see on sale right now is this 390W model ($68) which may or may not be suitable for your needs (I dunno how much of your PS' 750 Watts you're using).

https://www.amazon.com/CyberPower-CP685AVR-G-685VA-390W-Compact/dp/B00095W91O
http://www.newegg.com/Product/Product.aspx?Item=N82E16842102044&Tpk=N82E16842102044

 

[Ghostsoui]

From a quick Google search, the GX II 750Watt is a Bronze 80+ high-efficiency power supply. You really should connect high-efficiency power supplies to a UPS with simulated sine output. They get a lot of their efficiency from closely following the sine wave form of the AC power they receive.

When you plug them into a cheaper UPS which usually produces something closer to a sawtooth or truncated sawtooth output, it can cause the buzzing sound you're hearing and can damage the power supply over time.

From your UPS brand, I'm guessing you're in Mexico. If you can get access to U.S. mail-order stores, these simulated sine wave UPSes frequently go on sale. Unfortunately, you just missed a sale on a 800 Watt simulated sine wave UPS ($98). The only one I see on sale right now is this 390W model ($68) which may or may not be suitable for your needs (I dunno how much of your PS' 750 Watts you're using).

https://www.amazon.com/CyberPower-CP685AVR-G-685VA-390W-Compact/dp/B00095W91O
http://www.newegg.com/Product/Product.aspx?Item=N82E16842102044&Tpk=N82E16842102044

I'm using around 420w right now but what you are saying is that the problem is not the 1000va 500w? the problem is that I have a cheap UPS? I was going to buy this one:
No-Break CyberPower, 1500 VA, 50/60, 245 J, NEMA 5–15R
But it was very very expensive (160 dollars with the change)

So I bought this koblenz for about 95 dollars... and you just said that this can damage my PSU over time? oh well.. what is better then? should I keep the computer plugged on on this koblenz and when the lights go out turn the PC OFF or should I use my old regulator 1000w (this is not an UPS) and let the computer turn off when the power outages happen?

 

[Solandri]

The key feature to look for in the UPS is "pure sine wave output". If the Koblenz does not have it (or is doing a crappy job of it), you can use it but you should try to shut the computer down ASAP when the power goes out. I'm actually not sure how quickly a regular UPS can damage a high-efficiency power supply. I only know that you're not supposed to run them that way for extended periods of time.

 

[Ghostsoui]

The key feature to look for in the UPS is "simulated sine wave output".

Alright thank you I will look into it... but how about the PC? should I unplug it then?

 

[Solandri]

Ugh, looks like the marketing people took over the term. "Simulated" sine wave now refers to the truncated sawtooth pattern. You want a UPS with "pure sine wave" output. A "simulated" sine wave UPS *may* work. But it now just refers to something a little better than a generic UPS.

I'm actually not sure how quickly the UPS can damage the power supply. I just know that you're not supposed to let it run that way for too long.

 

[Ghostsoui]

Ugh, looks like the marketing people took over the term. "Simulated" sine wave now refers to the truncated sawtooth pattern. You want a UPS with "pure sine wave" output. A "simulated" sine wave UPS *may* work. But it now just refers to something a little better than a generic UPS.

I'm actually not sure how quickly the UPS can damage the power supply. I just know that you're not supposed to let it run that way for too long.

According to the manufacturer site this is a Simulated sine wave UPS you were saying just a moment ago that I need a Simulated sine wave UPS right? but now you are saying that I need a ''pure sine wave'' not a ''simulated'' right?

Just a last question, this Simulated, pure sine wave thing only affects my CPU when is using the battery or all the time when is plugged on the UPS?

 

[Solandri]

Yeah, I've been using UPSes a long time and back in the day (before high efficiency power supplies) there were regular UPSes which were safe for AC adapters and computer power supplies, and simulated sine wave UPSes which you needed for things like motors. I didn't realize the "simulated" sine wave term had been degraded to "sort of but not really a sine wave." And that the new term for UPSes for use with sensitive motors and HE PSes is "pure sine wave." Sorry. Hey, your question helped me learn something - thanks.

When the UPS is getting power from the wall, it passes that power straight to your computer. Most will clamp voltage spikes (surge suppression). Some will fill in during voltage drops aka browouts (voltage regulation).

Power comes from the UPS (simulated or pure sine wave) only when wall power drops or disappears. So the sine wave thing only affects your computer when the UPS is running off battery, not all the time.