Help to choose an UPS to eliminate the weird sound of the PSU while working with an inverter

[RodoGodo19]

Hi,

I live in Dominican Republic. We don't have electricity 24 hours a day, we need inverters to keep the lights on when the electricity goes off. When the inverter replace the electricity from the street, I notice a weird sound coming from the Power Supply, this weird sound disappear when the normal electricity goes back. I remember someone from my country saying that the electricity from Dominican Republic has a different type than others countries, I don't remember the exact name, sadly. I'm thinking on buying an UPS to solve this problem, I don't want to damage my Power Supply with time.

Questions:

1. Do you know which type of electricity the Power Supply work with?
2. Any good UPS for this purposes?, to convert the electricity from one type to another?
3. How many watts do I need?
4. Any of these models below will eliminate the weird noise from the Power Supply?

My PC:

• Dell 24" Monitor 1080p 60hz
• Intel Core i7-7700
• ASRock H270M-ITX/ac
• Corsair Vengeance LPX 16GB DDR4 2400MHz (2x8GB)
• Samsung 960 EVO
• 2x Seagate FireCuda SSHD 2TB 2.5-Inch
• EVGA GTX1080 FE
• Corsair SF600 Power Supply
• Fractal Design Node 202 Case
• Logitech Z200 Speakers
• Corsair M65 PRO RGB Mouse
• Dell Sk-8135 USB Wired Multimedia Keyboard

In a local store are available these UPS:

• APC
  BE425M-LM
  BE600M1
  BE850M2
  
  
• BES
  ACE_1K-BES

 

[Bill_Bright]

How many watts do I need?

If you go out to the eXtreme Power Supply Calculator and plug in your hardware components, it will recommend an UPS size for you. You might want add 30W for each monitor and 25W each for your modem and router if you want to protect them too (which I recommend).

Short of using that calculator, you need the UPS to support your computer's power supply plus any other devices you plan on connecting to the UPS. While most computers demand much less power than most users expect, that 425VA UPS is probably too small.

As seen here, once you convert VA to Watts, that 425VA UPS will supply just 255W after factoring in the Power Factor (PF) variable.

The general conservative rule of thumb is the power factor equals .6. And the formula for converting VA (Volt Amps) to Watts is VA x PF = Watts. So 425 x .6 = 255.

I am not familiar with BES UPS but APC have been my preferred brand for many years.

Your buzz is a common complaint when using inverters. You probably need to have a qualified electrician come test your house grounding to Earth.​

 

[SnakeDoctor]

You will need a Online / Pure sine wave UPS .Then the output of the ups power will be clean
The power direct from the Inverter will not be clean and can damage your pc as the power is fluctuating
The Apc ups you listed are Line interactive ups (entry level).Mainly to give you some backup power to shut down the pc incase of power failer

The BES ACE_1k-BES ,should work for you as its an Online Ups with Pure Sinewave

Unless you have a High end inverter

 

[infrared]

To build on what Bill said, you can actually measure or look up the Power Factor for your stuff, but it's better to add in some headroom anyway so the .6 value he gave as a rule of thumb is probably a good idea.

It sounds like your current inverter uses a square wave which is why you're getting that noise. It's not too much of a problem but it is a bit harsher on your computer's PSU. Definitely make sure you get a "pure sine wave" inverter/ups instead of "square wave/modified sine wave".

 

[Bill_Bright]

You will need a Online / Pure sine wave UPS .Then the output of the ups power will be clean

No you don't. Computer systems have been protected by line interactive UPS for decades with no problems. The call for online UPS is just a "marketing gimmick" to get users to believe they need to spend extra money on something they don't need.

The ATX Form Factor standard for computer power supplies already requires all ATX power supplies maintain ("hold up") output for any outage that lasts up to 17ms. Any decent UPS designed for computer support easily reacts within 10ms. So you do NOT need an online UPS.

And same with pure sine wave. Any 1/2 way decent AC/DC power supply can handle the "stepped sinewave" or "stepped approximation" waveform just fine. They have for the last 25 years with no problems so there is no reason to believe the much more reliable and robust power supplies of today can't either. They are much more capable at handling power line anomalies than PSUs of yesteryear.

The "marketing hype" for pure sine wave output UPS is just that, marketing hype. Pure sine wave UPS have only become popular in the last couple years because their prices have come down. The only devices that benefit from online and pure sine wave UPS are critical life support and health monitoring equipment in intensive care units and hospital emergency rooms.

Again, line interactive and pure sine wave UPS have only recently become the fad. They were not needed in the past, they are not needed today - especially with today's more robust computer power supplies.

Now I will say this; like computer power supplies, there are budget (entry level) UPS. You do want to invest in a good one and avoid the budget models. You don't have to spend $400 on a UPS, but you should invest in a decent one.

If you can find a pure sine wave online UPS that is reasonably priced, then no harm in getting one. But there is no need to go out of your way to find one.

Just to add to/contradict Bill slightly, power factor isn't a fixed value of .6 (although it's good to use as rule of thumb as he says, headroom is good!)

Contradict?? Please note I never said it was a fixed value of anything. In fact, in addition to saying it was a "rule of thumb", I specifically said "Power Factor (PF) variable". Also, I note many UPS makers use that value. If you convert the formula VA x PF = W to find PF, you come up with PF = W/VA. Plug in the VA and Watts value from that APC UPS link (425VA and 255W), you will find they used .6 for the PF too.

Now I see the OP has posted this same question on at least one other site (https://linustechtips.com/main/topi...nd-of-the-psu-while-working-with-an-inverter/). You should post at one site at a time.

 

[infrared]

Contradict?? Please note I never said it was a fixed value of anything. In fact, in addition to saying it was a "rule of thumb", I specifically said "Power Factor (PF) variable". Also, I note many UPS makers use that value. If you convert the formula VA x PF = W to find PF, you come up with PF = W/VA. Plug in the VA and Watts value from that APC UPS link (425VA and 255W), you will find they used .6 for the PF too.

Now I see the OP has posted this same question on at least one other site (https://linustechtips.com/main/topi...nd-of-the-psu-while-working-with-an-inverter/). You should post at one site at a time.

I edited my post because i noticed you said variable, you must have finished your reply before you saw my edit.

Also I'm a qualified electrician so you don't need to tell me how power factor works.

EDIT:

Also you say an on-line ups isn't needed, but to clean up the power from the inverter he does in fact need an on-line/double conversion UPS, and he'll want a pure sine wave otherwise he'll have the same problem with the PSU making noise as he did before. A line interactive ups won't clean up the input power, it'll only step in if there's a power outage which isn't the issue the OP is dealing with.

 

[RodoGodo19]

Turns out my Inverter is old and can not deliver clean electricity like you said.
I will sell my Inverter very cheap to buy a new Inverter of 2017 which has "sinusoidal" electricity, at least that is the name that the local store said. It will give me pure and clean electricity and will eliminate the noises of my devices.

Thanks for your advices, I will follow your steps one by one.

 

[Bill_Bright]

Turns out my Inverter is old and can not deliver clean electricity like you said.

That could certainly be the case, but I would still check its wiring first - especially since it is old. Make sure they are all clean and tight and especially that there is a solid path to Earth ground.

I edited my post because i noticed you said variable, you must have finished your reply before you saw my edit.

No, everyone can tell by the time stamps my reply was posted 12 minutes before you edited your post.

Also I'm a qualified electrician so you don't need to tell me how power factor works.

Now that's just being silly. So we are suppose to automatically know your background? Come on! Nothing in your sig or profile says you are qualified to do squat.

 

[infrared]

No, everyone can tell by the time stamps my reply was posted 12 minutes before you edited your post.
Now that's just being silly. So we are suppose to automatically know your background? Come on! Nothing in your sig or profile says you are qualified to do squat.

Well that just means I spent ages on my edit then, doesn't mean I'm lying about time frames wtf.
I didn't say I expected you to know that, just informing you that I don't need your teaching in this subject. I think the key point is don't assume you know more than others if you don't know their background.

Turns out my Inverter is old and can not deliver clean electricity like you said.
I will sell my Inverter very cheap to buy a new Inverter of 2017 which has "sinusoidal" electricity, at least that is the name that the local store said. It will give me pure and clean electricity and will eliminate the noises of my devices.

Nice one, that'll do the trick. And Sinusoidal is the same as pure sine wave, that'll do the trick nicely

 

[Bill_Bright]

and will eliminate the noises of my devices.

If properly grounded to Earth.

Well that just means I spent ages on my edit then, doesn't mean I'm lying about time frames wtf.

I never said you were lying. I was just pointing out I could not have seen your edit because I posted my reply before you made it.

As for assuming, as a regular helper on forums, it is best to never assume those reading have expertise in the technical fields. And I don't assume I know more than others. I just don't assume others know as much in particular fields as I do. That's not arrogance. It is just knowing that I've been around the block a time or two. And the fact I have been around awhile is why can help on these sites. I also include that link in my sig so others can see and hopefully trust that I might know a bit about electronics without having to assume anything or fear I will lead them astray.

 

[infrared]

Good for you, you can go round with your stuff in your sig saying how good you are all you want, you still don't get everything right (no-one is always right). So how about we help the people that ask for help, and not start a pissing contest or petty argument every time someone else wants to contribute to the topic or question something you said.

 

[FordGT90Concept]

I have four of these and they're great: CyberPower CP1350PFCLCD. Should be adequate for your needs too.

Not saying it will eliminate the capacitor whine...because it probably won't.

 

[Bill_Bright]

I have four of these and they're great: CyberPower CP1350PFCLCD.

I have one of the 1000VA models of that UPS and while I prefer APC, I have no complaints about this one. I particularly like the LCD information display. While most UPS provide that information through a communications cable and Windows app, it is really nice to be able to check status right at the UPS without having to fire-up or wake the computer.

In fact, it was really nice just last week when we came home and all the UPS in the house were beeping (I have an UPS on each computer, my home theater/TV system, even my garage door opener). Yet the house lights were still on! ??? A quick check on that panel showed the incoming voltage was 143VAC!!!! It should be ~120VAC. A quick check with my multimeter confirmed, 142.8VAC and the 220VAC outlet in the garage was showing 285.6VAC. Not good - especially for things like AC and refrigerator compressors.

I called the power company and they came right out. It seems something happened to the transformer on the pole. They had to kill power to the whole neighborhood and move the tap. Now we are still a little high at 122VAC but all the UPS (and I) are happy. I am told we are now scheduled to get a new transformer as the one there is 30 years old and the tap they used should be putting out 220VAC to the drop to the house, but is still too hot at 244VAC (122VAC single phase). But at least that is a safe level.

Had I not had an UPS on my computer I probably would have fired up the computer and with the voltage being that hot, might have put too much strain on the PSU. The LCD panel made troubleshooting a snap. It also allowed me to easily explain to the power company trouble desk what was going on so they sent someone out so quickly.

I note those LCD panels are not typically found on entry level UPS.

Also, a simple surge and spike protector would not have done anything to protect the connected equipment about that high voltage.