Question Advice for UPS purchase ?

Aeacus

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the best UPS to get
The Delta Conversion Online UPS. Will cost a fortune, but hands down, the best UPS design there is (at least currently).

signature has my systems specs
With that kind of hardware, you can forget "budget" and "value".

Simulated sine wave UPS - not going to happen, especially if you want "the best".


UPSes can output 3 different kinds of waveform:
1. square wave - cheapest of the three. ONLY good for robust hardware, like power generators and motors.
2. simulated sine wave (aka stepped-approximated sine wave) - mediocre price. Good for most home appliances (e.g fridge, washing machine, lights).
3. true/pure sine wave - high price. It is the same as you get out of the wall socket. ONLY waveform good for sensitive electronics, like medical equipment, TVs, PC PSUs.

So, you want to have true/pure sine wave UPS. Simulated sine wave UPS may also work, but it may not. More of that below;

When looking for an UPS, there are 2 things to look out:
1. Output waveform (square wave, simulated sine wave and true/pure sine wave)
2. Design (stand-by, line-interactive and online)

From here you can read about the differences between output waveform,
link: https://suvastika.com/why-choose-a-sinewave-inverter-ups/

And here are explanations about the UPS design,
link: https://www.eetimes.com/document.asp?doc_id=1272971

Waveform and design
For PCs, line-interactive UPS would be more than enough since PSUs can easily handle the 2ms to 5ms transfer time of line-interactive UPS.
As far as output waveform goes, true/pure sine wave UPS is best used. While simulated sine wave UPSes are cheaper than true/pure sine wave UPSes, PSUs with Active PFC aren't compatible with simulated sine wave. You might get simulated sine wave UPS running with Active PFC PSU but there can be some major issues. Here's what, how and why.

How do you know which PSUs have Active PFC and which ones don't?
Simple, every PSU that has 80+ certification (e.g 80+ Bronze or 80+ Gold) has Active PFC.

What is Active PFC?
Further reading: https://en.wikipedia.org/wiki/Power_factor#Power_factor_correction_(PFC)_in_non-linear_loads

What can happen when using simulated sine wave UPS with Active PFC PSU?
When simulated sine wave UPS switches over to the battery power, one of 3 things can happen:
1. UPS displays error resulting PC to shut down immediately.
2. UPS shuts down resulting PC to shut down immediately.
3. UPS switches to battery power resulting PC to power off from UPS (PC stays on).

Why it happens?
Simulated sine wave UPS produces a zero output state during the phase change cycle resulting in a power “gap”. This gap may cause power interruption for active PFC PSUs when switching from AC power output to simulated sine wave output (battery mode).

What to do next?
As stated above, your PC can run off from simulated sine wave UPS but be prepared when you face issues with it. When issues do rise, your best bet would be returning the simulated sine wave UPS and getting true/pure sine wave UPS. Or you can go with true/pure sine wave UPS off the bat.

Wattage
As far as UPS wattage goes, you need to consider the power draw of your PC and monitors. Maybe speakers and wi-fi router too if you plan to plug those into the UPS as well. Though, printers, scanners and other such hardware (full list on your UPS manual) don't plug to the UPS since their startup power draw is way too much for UPS to handle and you can fry your UPS.

Taking PSU's max wattage as a baseline is good idea since it will give your UPS more headroom and you can get longer runtime out of your UPS. Since your PSU is 1000W, at least one monitor is added on top of it. Depending on the monitor size, they use between 23W to 52W. Wi-fi routers don't consume much power. For example, my Cisco EPC3940L consumes 12V at 3A which means 36W.

Good UPS brands to go for are CyberPower, TrippLite and APC. While there are other UPS brands as well, those three are the best out there.
Note: The more powerful UPS you have, the longer UPS can keep your PC running before it's battery is empty.


With all that being said, good UPS to go for is: CyberPower CP1600EPFCLCD 1600VA/1000W (true/pure sine wave, line-interactive) UPS;
specs: https://www.cyberpower.com/eu/en/product/sku/cp1600epfclcd
store link: https://www.dicksmith.co.nz/dn/buy/flashtrend-pfc-sinewave-series-1600va-1000w-expd56-6199592/

My 2x PCs are also backed up by UPSes, 1x UPS per PC. I have two of these in use: CyberPower CP1300EPFCLCD (1300VA/780W, true/pure sine wave, line-interactive),
specs: https://www.cyberpower.com/hk/en/product/sku/CP1300EPFCLCD

My UPSes are actually predecessor of CP1600EPFCLCD and since mine are already 6 years old, i'm planning to replace them with the very same, new version, i linked for you. But i'm going with 1350VA/810W ones.
 
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Eamonn100

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The Delta Conversion Online UPS. Will cost a fortune, but hands down, the best UPS design there is (at least currently).


With that kind of hardware, you can forget "budget" and "value".


Simulated sine wave UPS - not going to happen, especially if you want "the best".


UPSes can output 3 different kinds of waveform:
1. square wave - cheapest of the three. ONLY good for robust hardware, like power generators and motors.
2. simulated sine wave (aka stepped-approximated sine wave) - mediocre price. Good for most home appliances (e.g fridge, washing machine, lights).
3. true/pure sine wave - high price. It is the same as you get out of the wall socket. ONLY waveform good for sensitive electronics, like medical equipment, TVs, PC PSUs.

So, you want to have true/pure sine wave UPS. Simulated sine wave UPS may also work, but it may not. More of that below;

When looking for an UPS, there are 2 things to look out:
1. Output waveform (square wave, simulated sine wave and true/pure sine wave)
2. Design (stand-by, line-interactive and online)

From here you can read about the differences between output waveform,
link: https://suvastika.com/why-choose-a-sinewave-inverter-ups/

And here are explanations about the UPS design,
link: https://www.eetimes.com/document.asp?doc_id=1272971

Waveform and design
For PCs, line-interactive UPS would be more than enough since PSUs can easily handle the 2ms to 5ms transfer time of line-interactive UPS.
As far as output waveform goes, true/pure sine wave UPS is best used. While simulated sine wave UPSes are cheaper than true/pure sine wave UPSes, PSUs with Active PFC aren't compatible with simulated sine wave. You might get simulated sine wave UPS running with Active PFC PSU but there can be some major issues. Here's what, how and why.

How do you know which PSUs have Active PFC and which ones don't?
Simple, every PSU that has 80+ certification (e.g 80+ Bronze or 80+ Gold) has Active PFC.

What is Active PFC?
Further reading: https://en.wikipedia.org/wiki/Power_factor#Power_factor_correction_(PFC)_in_non-linear_loads

What can happen when using simulated sine wave UPS with Active PFC PSU?
When simulated sine wave UPS switches over to the battery power, one of 3 things can happen:
1. UPS displays error resulting PC to shut down immediately.
2. UPS shuts down resulting PC to shut down immediately.
3. UPS switches to battery power resulting PC to power off from UPS (PC stays on).

Why it happens?
Simulated sine wave UPS produces a zero output state during the phase change cycle resulting in a power “gap”. This gap may cause power interruption for active PFC PSUs when switching from AC power output to simulated sine wave output (battery mode).

What to do next?
As stated above, your PC can run off from simulated sine wave UPS but be prepared when you face issues with it. When issues do rise, your best bet would be returning the simulated sine wave UPS and getting true/pure sine wave UPS. Or you can go with true/pure sine wave UPS off the bat.

Wattage
As far as UPS wattage goes, you need to consider the power draw of your PC and monitors. Maybe speakers and wi-fi router too if you plan to plug those into the UPS as well. Though, printers, scanners and other such hardware (full list on your UPS manual) don't plug to the UPS since their startup power draw is way too much for UPS to handle and you can fry your UPS.

Taking PSU's max wattage as a baseline is good idea since it will give your UPS more headroom and you can get longer runtime out of your UPS. Since your PSU is 1000W, at least one monitor is added on top of it. Depending on the monitor size, they use between 23W to 52W. Wi-fi routers don't consume much power. For example, my Cisco EPC3940L consumes 12V at 3A which means 36W.

Good UPS brands to go for are CyberPower, TrippLite and APC. While there are other UPS brands as well, those three are the best out there.
Note: The more powerful UPS you have, the longer UPS can keep your PC running before it's battery is empty.


With all that being said, good UPS to go for is: CyberPower CP1600EPFCLCD 1600VA/1000W (true/pure sine wave, line-interactive) UPS;
specs: https://www.cyberpower.com/eu/en/product/sku/cp1600epfclcd
store link: https://www.dicksmith.co.nz/dn/buy/flashtrend-pfc-sinewave-series-1600va-1000w-expd56-6199592/

My 2x PCs are also backed up by UPSes, 1x UPS per PC. I have two of these in use: CyberPower CP1300EPFCLCD (1300VA/780W, true/pure sine wave, line-interactive),
specs: https://www.cyberpower.com/hk/en/product/sku/CP1300EPFCLCD

My UPSes are actually predecessor of CP1600EPFCLCD and since mine are already 6 years old, i'm planning to replace them with the very same, new version, i linked for you. But i'm going with 1350VA/810W ones.
Thank you very much for all this. As you can imagine... me not being a tec guy... knew it was was best to ask someone... and I'd only waste time and money doing it myself. Thanks again.

Just one question... Going for the reamended type but with more power, ie... more than 1000W will buy me more run time if the power went out?
 

Aeacus

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Just one question... Going for the reamended type but with more power, ie... more than 1000W will buy me more run time if the power went out?
Yes.

Though, UPS'es idea (line-interactive topology) is to sustain PC as long as you can save your work and then shut down the PC safely. Usually 5mins is good. Maybe even 10mins. E.g that CyberPower 1600VA/1000W UPS has full load (1000W) runtime of 2.6 mins. On half load (500W), it has runtime of 9.7mins.

But UPS is not a battery pack that you can run your PC off at all times. If you want that, buy a gasoline/diesel powered electric generator that provides you electricity when main electricity is off OR on-line UPS.

Also, there is no higher UPS in CyberPower PFC Sinewave series than 1600VA/1000W unit. If you want to go higher, better look towards double-conversion or delta-conversion on-line UPS. Those start from kW range and go into MW range (1000W = 1kW, 1000kW = 1MW). On-line UPSes are used to back up entire server parks.

On-line UPS topology is such, where power is constantly taken from the UPS battery and mains is used to recharge the battery. So, when main electricity cuts off, there is 0 transfer time. Only battery level is starting to drain. Downside is, that since battery is in constant use, it wears out more quickly. But on-line UPSes have several batteries, so, when one fails, the failed one can be replaced without ever cutting the power source to the servers.
 
aeacus has explained things very well. The key thing is the number of watts only indicate what the device is capable of producing it does not directly tell you how long it can produce the power. You can think of the watt value as a circuit breaker value. You do not want to plug equipment into it that exceed that value.

So a kinda dirty way to guess how long a UPS will last is to look up what kind of batteries it uses. You are going to have to replace them in about 3 years anyway so its good to know if it uses something very strange and costly.

Most common consumer UPS uses 1 or 2 12 volt 9ah batteries. This means the battery can produce 108 watts for a hour. So in theory ignoring all the energy loss do to conversion to AC if your pc only used 108 watts it would last 1 hour and if it uses 1080 watts it would last 6 minutes. It is much more complex since the faster you draw power the more that is lost to heat.

In general buy a UPS that has a WATT number larger than the maximum your equipment will ever use. Then to compare UPS for run time add up the number of AH the batteries have. The more total amp hours the longer it will run.
If you look at UPS used for server use in a very small data center it is not uncommon to have 4 9ah batteries.

Now if dig around you will find many posts/articles that talk about adding huge external lead acid batteries with very large AH ratings to UPS. This works but the parts in a UPS are only designed to run for so many hours at a time so you in effect wear them out from overuse. The more realistic option when you want a UPS that last a long time is to look into solar energy battery systems and just charge them with city power rather than solar panels.