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UPS advice. Do you really need pure sine wave?

FlyingScotsmanZA

FlyingScotsmanZA

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Hi, looking to buy a UPS for my desktop setup. We've been having a ton of unexpected power outages in my area and with the price of components going crazy I want to protect my shit.

I have an APC BX700UI UPS that I bought in 2016 still running for my NAS, but I never got one for my desktop setup.

My current setup is two monitors (AW3423DWF & G2724D), Bookshelf speakers (Edifier R200DB) and my PC (7800X3D, RX9070, 32GB RAM, 2x2TB SSD).

Originally I was looking at this unit.

Takealot.com: Online Shopping | SA's leading online store

South Africa's leading online store. Fast, reliable delivery to your door. Many ways to pay. Shop anything you can imagine: TVs, laptops, cellphones, kitchen appliances, toys, books, beauty & more. Shop the mobile app anytime, anywhere.
www.takealot.com www.takealot.com

But as I dug deeper I was reading about pure sine wave vs modified sine wave. I've seen a number of posts saying that using modified sine wave causes issues, mainly humming, with audio equipment. Is that correct?

The cheapest APC pure sign wave unit they have is R6k (normal price is R15k wtf) which is quite a lot more. Don't really want to spend that much tbh.

Takealot.com: Online Shopping | SA's leading online store

South Africa's leading online store. Fast, reliable delivery to your door. Many ways to pay. Shop anything you can imagine: TVs, laptops, cellphones, kitchen appliances, toys, books, beauty & more. Shop the mobile app anytime, anywhere.
www.takealot.com www.takealot.com

So yeah, looking for advice / info.

Thanks.
 
Why does the replacement have to be APC? They're extremely overpriced, normally several times the price of competing products.
 
FlyingScotsmanZA said:
Hi, looking to buy a UPS for my desktop setup. We've been having a ton of unexpected power outages in my area and with the price of components going crazy I want to protect my shit.

I have an APC BX700UI UPS that I bought in 2016 still running for my NAS, but I never got one for my desktop setup.

My current setup is two monitors (AW3423DWF & G2724D), Bookshelf speakers (Edifier R200DB) and my PC (7800X3D, RX9070, 32GB RAM, 2x2TB SSD).

Originally I was looking at this unit.

Takealot.com: Online Shopping | SA's leading online store

South Africa's leading online store. Fast, reliable delivery to your door. Many ways to pay. Shop anything you can imagine: TVs, laptops, cellphones, kitchen appliances, toys, books, beauty & more. Shop the mobile app anytime, anywhere.
www.takealot.com www.takealot.com

But as I dug deeper I was reading about pure sine wave vs modified sine wave. I've seen a number of posts saying that using modified sine wave causes issues, mainly humming, with audio equipment. Is that correct?

The cheapest APC pure sign wave unit they have is R6k (normal price is R15k wtf) which is quite a lot more. Don't really want to spend that much tbh.

Takealot.com: Online Shopping | SA's leading online store

South Africa's leading online store. Fast, reliable delivery to your door. Many ways to pay. Shop anything you can imagine: TVs, laptops, cellphones, kitchen appliances, toys, books, beauty & more. Shop the mobile app anytime, anywhere.
www.takealot.com www.takealot.com

So yeah, looking for advice / info.

Thanks.
Click to expand...
For the stuff you mention, all of them probably have a switch mode power supply which means it’s anyway chopping that sine wave to convert the ac to dc.

Where sine wave is important is if something has a motor. For Audio, it’s probably the types that have a regulated power supply that may cause the hum.
 
Oj0 said:
progenix.co.za

FSP Champ Tower 1K 1000VA 230V Online UPS — Best Deals at Progenix — South Africa

FSP Champ is the high density version of double-conversion online UPS with an output power factor that reaches 0.9 and featured with ECO mode for energy saving. True double-conversion. Microprocessor control optimizes reliability. Input power factor corre
progenix.co.za progenix.co.za

Half the price of the APC - there's one left.
Click to expand...
Have you owned one?

Reviews on takealot complaining about loud constant fan noise. Ideally looking for one that is silent until the there's an issue with mains and it switches to battery backup. Don't really care about noise when it's on battery as it'll only be on for 2 minutes to safely shutdown my system, but if there is constant fan noise 24/7 even when not on battery, that would drive me insane.
 
@FlyingScotsmanZA What is your expectation?
1) I want to game for an hour on my UPS while power is down? Get a power trolley.
2) I want 10 minutes and a signal via USB to shut everything down cleanly? Get a UPS.

Reason I ask is why do you worry about audio while shutting down.

Technically, square wave and modified sine wave inverters have extra harmonics that leads to extra heat and circuit noise in electronics. It will have an influence on your hardware, but how much is anyone's guess. You can mitigate it with extra power filters (more money). Better to buy correctly first time.

Most cheap UPSes are not really made to carry the load for long, more of a clean shutdown.
 
FlyingScotsmanZA said:
Have you owned one?

Reviews on takealot complaining about loud constant fan noise. Ideally looking for one that is silent until the there's an issue with mains and it switches to battery backup. Don't really care about noise when it's on battery as it'll only be on for 2 minutes to safely shutdown my system, but if there is constant fan noise 24/7 even when not on battery, that would drive me insane.
Click to expand...
That's a result of it being an online UPS. A line interactive UPS won't save you from much other than data loss.

A line-interactive UPS will protect against dips in the power but won't do anything about high voltages or dirty power. The way they work is as a straight pass-through of the AC power until the voltage drops below a certain point, and then they swap to battery power.

On online UPS (also referred to as a double conversion UPS), on the other hand, always runs from battery power even when AC power is stable. That way, there is no switching time and the output is always a solid 220/230/240v. The downside of an online UPS is that they have a fan running constantly (as they're constantly "in use"), they're not quite as energy efficient as their circuitry is always active, and they're more expensive.

A line-interactive UPS will be nothing more than something to keep you running long enough to save and shut down in case of power loss, while an online UPS is more of a "power conditioner." Neither are designed to protect against lightning, but the online UPS has a far higher chance of saving your hardware as it isn't a straight pass-through of AC power. I have recorded in excess of 450v on my online UPS with a nearby lightning strike which sent the UPS into protection mode and shut it down instantly, but four years later there's still zero damage to it or any of the components connected. They aren't designed for this, they might not protect you against lightning strikes, and it's very possible for one to kill the UPS and void its warranty, so this is merely to show that they CAN offer a form of protection that a line interactive UPS does not. A line interactive UPS would likely have resulted in a lot of dead hardware.

To put it in the most basic terms,

  • Line interactive UPS: Is the power above 170v or below 250v (outside of the UPS's operating range)? If so, I'm going to send power straight from the wall to whatever is plugged into it, whether it's dirty or high. If it's between 0v and 170v, give me about 10ms to swap over to battery.
  • Online UPS: I really don't care what the power is coming IN, you're running on battery at a solid voltage 24/7 and I'll keep the batteries topped up with AC power. If the AC power drops too low or too high, such as 0v to 170v or 250v+ in the example above, I'll just turn off the charging circuit and run everything on battery until power is back to normal, without the battery being recharged during this time.

This also gives the online UPS the ability to smooth out things such as frequency fluctuations. If your mains are fluctuating between 49.7 Hz and 50.2 Hz, you'll get the same output (49.7 Hz to 50.2 Hz) from a line interactive UPS while an online UPS will output 50.0 Hz. Most modern PSUs have a wide input range (50-60 Hz so they can be used worldwide), but they prefer a stable frequency and don't take kindly to fluctuations while in use.
 
FlyingScotsmanZA said:
Have you owned one?

Reviews on takealot complaining about loud constant fan noise. Ideally looking for one that is silent until the there's an issue with mains and it switches to battery backup. Don't really care about noise when it's on battery as it'll only be on for 2 minutes to safely shutdown my system, but if there is constant fan noise 24/7 even when not on battery, that would drive me insane.
Click to expand...
I still own one.

Does the fan annoy me - yes
Do I feel safe leaving my pc plugged in - also yes.
 
ovisser1 said:
I still own one.

Does the fan annoy me - yes
Do I feel safe leaving my pc plugged in - also yes.
Click to expand...
Is the fan on 24/7.

All the UPS I had would only turn the fan on when it’s running on battery or if it’s charging the battery.
 
Confucius said:
Is the fan on 24/7.

All the UPS I had would only turn the fan on when it’s running on battery or if it’s charging the battery.
Click to expand...
Always on yes, most online are always on.

Its so loud that I sometimes switch it off and unplug from the wall or just outright close the study door.

Switching off still keeps the fan on, even if output is off.
 
disquisitive.ape said:
@FlyingScotsmanZA What is your expectation?
1) I want to game for an hour on my UPS while power is down? Get a power trolley.
2) I want 10 minutes and a signal via USB to shut everything down cleanly? Get a UPS.

Reason I ask is why do you worry about audio while shutting down.

Technically, square wave and modified sine wave inverters have extra harmonics that leads to extra heat and circuit noise in electronics. It will have an influence on your hardware, but how much is anyone's guess. You can mitigate it with extra power filters (more money). Better to buy correctly first time.

Most cheap UPSes are not really made to carry the load for long, more of a clean shutdown.
Click to expand...

Option 2

I'm not worried about audio while shutting down. I'm worried about what you mentioned in the next paragraph, heat / circuit noise or my speakers humming while connected to the UPS. That will irritate me.

ovisser1 said:
Always on yes, most online are always on.

Its so loud that I sometimes switch it off and unplug from the wall or just outright close the study door.

Switching off still keeps the fan on, even if output is off.
Click to expand...

Yeah this will drive me insane. I've spent too much money on making my PC as silent as possible to have a wind turbine UPS next to it. Can you swap out the fan?

Oj0 said:
That's a result of it being an online UPS. A line interactive UPS won't save you from much other than data loss.

A line-interactive UPS will protect against dips in the power but won't do anything about high voltages or dirty power. The way they work is as a straight pass-through of the AC power until the voltage drops below a certain point, and then they swap to battery power.

On online UPS (also referred to as a double conversion UPS), on the other hand, always runs from battery power even when AC power is stable. That way, there is no switching time and the output is always a solid 220/230/240v. The downside of an online UPS is that they have a fan running constantly (as they're constantly "in use"), they're not quite as energy efficient as their circuitry is always active, and they're more expensive.

A line-interactive UPS will be nothing more than something to keep you running long enough to save and shut down in case of power loss, while an online UPS is more of a "power conditioner." Neither are designed to protect against lightning, but the online UPS has a far higher chance of saving your hardware as it isn't a straight pass-through of AC power. I have recorded in excess of 450v on my online UPS with a nearby lightning strike which sent the UPS into protection mode and shut it down instantly, but four years later there's still zero damage to it or any of the components connected. They aren't designed for this, they might not protect you against lightning strikes, and it's very possible for one to kill the UPS and void its warranty, so this is merely to show that they CAN offer a form of protection that a line interactive UPS does not. A line interactive UPS would likely have resulted in a lot of dead hardware.

To put it in the most basic terms,

  • Line interactive UPS: Is the power above 170v or below 250v (outside of the UPS's operating range)? If so, I'm going to send power straight from the wall to whatever is plugged into it, whether it's dirty or high. If it's between 0v and 170v, give me about 10ms to swap over to battery.
  • Online UPS: I really don't care what the power is coming IN, you're running on battery at a solid voltage 24/7 and I'll keep the batteries topped up with AC power. If the AC power drops too low or too high, such as 0v to 170v or 250v+ in the example above, I'll just turn off the charging circuit and run everything on battery until power is back to normal, without the battery being recharged during this time.

This also gives the online UPS the ability to smooth out things such as frequency fluctuations. If your mains are fluctuating between 49.7 Hz and 50.2 Hz, you'll get the same output (49.7 Hz to 50.2 Hz) from a line interactive UPS while an online UPS will output 50.0 Hz. Most modern PSUs have a wide input range (50-60 Hz so they can be used worldwide), but they prefer a stable frequency and don't take kindly to fluctuations while in use.
Click to expand...

Thanks for this. I didn't know the difference. So does anyone make an online UPS that is quiet? The noise factor is a big deal for me. Don't really want a jet engine while I'm trying to chill or work.
 
FlyingScotsmanZA said:
Yeah this will drive me insane. I've spent too much money on making my PC as silent as possible to have a wind turbine UPS next to it. Can you swap out the fan?
Click to expand...
Well, rectron did once under warranty when it started sounding even worse than stock - bearing started rattling like a snake about 1 year in, no issues since.
But I have not checked if its a simple fan connector to install a noctua or something along those lines to quiet it down.
 
ovisser1 said:
Always on yes, most online are always on.

Its so loud that I sometimes switch it off and unplug from the wall or just outright close the study door.

Switching off still keeps the fan on, even if output is off.
Click to expand...
Why do you need it though. Thought your whole house was covered by the inverter.
 
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