Corsair CX550 issue with UPS

[whitestar_999]

I recently got a corsair CX550 psu & for first 4-5 days it worked perfectly but then it started having a strange issue.Whenever there is a power cut & I am playing some video with madvr using 1050Ti(for those who don't know madvr improves picture quality by using gfx card for running its upscaling algorithms so load is very similar to running a game) system just shuts down along with long constant beep from UPS indicating overload.This does not happen when system is idle/not playing any video.

However the strange thing is that my FSP 400W psu works perfectly in same situation & even able to provide backup to system(playing same video) for at least 30 seconds(manually turned off mains power to UPS but didn't tested beyond that) proving that UPS batteries have enough capability left even after 14 months(intex generic 600VA UPS).

So my question is for those who use activePFC psu like CX550(or any recent usually recommended psu because they all come with activePFC nowadays) with your usual intex/luminous/zebronics etc UPS.Do these psu works fine with a 600VA UPS when under load with a low power gfx card like 1050Ti?

Tagging @gta5 @chimera201 for your inputs.

 

[chimera201]

Well the hold up time for CX550 seems to be about 12ms according to Cybenetics tests which is less than the recommended 17 ms. Possibly the cause for the shutdown.
*www.cybenetics.com/code/pdf.php?id=CUj

 

[whitestar_999]

Thanks for this crucial info.Any idea about APC 600VA UPS holdup time & if possible FSP Saga II 400W/similar psu holdup time.Currently I have Intex 600VA UPS which works fine with FSP but not with CX550.

 

[chimera201]

It's not hold up time for UPS but rather transfer time. Also there would be some additional delay between the UPS and PSU so it won't be exact value to value match. Basically the transfer time needs to be much lesser.
Seems it's 10ms for 600VA APC one:
*www.apc.com/salestools/JGNY-9477YW/JGNY-9477YW_R1_EN.pdf

 

[gta5]

As far as I know

I don't think it is because of hold up time..

Hold up time is usually measured at full load, so that 12 ms figure is if you are using your PSU at full load it will only be able to power up your pc for 12ms after power is removed

Your total pc power consumption won't be more than 250 watts even at full load with this cofig, so your hold up time would be more than 25ms roughly.

Additionaly if hold up time was responsible then PC would restart .. Here I don't think PC is restarting but complete shutdown with overload beep..

Also most decent ups won't have transfer time of more than 10ms

This is most likely because of high inrush current , apfc psus have high voltage primary capacitors and they draw a lot of current at start regardless of actual load and can be very high more than even full load .. PSU uses NTC thermistor for this purpose to limit inrush current , but still they will draw a lot of current.. Depending upon the size of ntc thermistor and size of primary capacitors used, apfc circuitry it can vary

At low loads , inrush current isn't high to trigger overload condition of UPS , plus capacitors will be less discharged because of low load at idle and will draw less inrush current
Till the time ups resumes

But at high loads , primary capacitors would discharge faster , resulting in more inrush current on top of already high demanding main PC load

This differs from PSU to PSU. Some can use beefier primary caps like in high wattage models but they may have appropriately sized thermistors to even play well 600 va ups like for eg RM650x of member topgear mentioned in his thread

Computers containing PFC (Power Factor Corrected) power supplies and their use Back-UPS and Smart-UPS SC with Step Approximated Sine waves.

Your fsp unit may simply be drawing less inrush current at full load than cx550

 

[whitestar_999]

That's some good info @gta5 .Does this mean I have to get a 1000/1100VA ups & just getting a 600VA APC ups won't be enough?That's a lot of unnecessary money spend for a system that draws less than 300W(I will upgrade pentium G620 to a Ryzen 3 1200 or 2200G in future but gfx card will remain 1050Ti).

 

[gta5]

You have a main sinewave inverter right ? And you use that to power your PC during power cuts ?

Remove UPS

If your inverter is able to sustain the load when you are playing movie during power cut , then why not directly use that..

It is safer than back ups

Maybe APC 600va may have higher tolerance for inrush current than your current one .. Which may be enough to power your load.. There is a slight chance it could be battery also

Maybe 800va might work , you will have to do hit and trial to see which one will suit.. "Nothing can be said with sureity"

Or maybe try microtek/luminous ones etc of higher Va as they are cheaper, since you only need to run this for few milliseconds till your main inverter resumes power .. You can get these on trial basis I think because of wide availability in offline shops, if you can't arrange one from friend etc for testing

.. Pay a few hundred extra to dealer , and return in few hours after buying if it doesn't work

But still if your sinewave supports your load , then that is the best option.. And no expenditure + Safer for PSU

 

[dexterz]

I recently got a corsair CX550 psu & for first 4-5 days it worked perfectly but then it started having a strange issue.Whenever there is a power cut & I am playing some video with madvr using 1050Ti(for those who don't know madvr improves picture quality by using gfx card for running its upscaling algorithms so load is very similar to running a game) system just shuts down along with long constant beep from UPS indicating overload.This does not happen when system is idle/not playing any video.

However the strange thing is that my FSP 400W psu works perfectly in same situation & even able to provide backup to system(playing same video) for at least 30 seconds(manually turned off mains power to UPS but didn't tested beyond that) proving that UPS batteries have enough capability left even after 14 months(intex generic 600VA UPS).

So my question is for those who use activePFC psu like CX550(or any recent usually recommended psu because they all come with activePFC nowadays) with your usual intex/luminous/zebronics etc UPS.Do these psu works fine with a 600VA UPS when under load with a low power gfx card like 1050Ti?

I had this exact same problem few years back and again a few months ago. I used a Corsair HX650 PSU with APC 700VA UPS. It used to work fine when the system was idle or not playing any games but the system shut down/restarted when I was playing a game during the power cut. Manually switching off power supply didnt cause a restart.
Both the times this happened when it was close to my battery replacement dates. Since my UPS was already 6years old, I replaced it with a Numeric 1kva and haven't had any abrupt shutdowns or restarts. Hope this helps

 

[whitestar_999]

^^Can you tell me how old were the APC ups batteries when this problem started(you said UPS was 6 years old) & how much the numeric 1kva costed you?

 

[whitestar_999]

You have a main sinewave inverter right ? And you use that to power your PC during power cuts ?

Remove UPS

If your inverter is able to sustain the load when you are playing movie during power cut , then why not directly use that..

It is safer than back ups

Maybe APC 600va may have higher tolerance for inrush current than your current one .. Which may be enough to power your load.. There is a slight chance it could be battery also

Maybe 800va might work , you will have to do hit and trial to see which one will suit.. "Nothing can be said with sureity"

Or maybe try microtek/luminous ones etc of higher Va as they are cheaper, since you only need to run this for few milliseconds till your main inverter resumes power .. You can get these on trial basis I think because of wide availability in offline shops, if you can't arrange one from friend etc for testing

.. Pay a few hundred extra to dealer , and return in few hours after buying if it doesn't work

But still if your sinewave supports your load , then that is the best option.. And no expenditure + Safer for PSU

The thing is inverter is meant for whole house & because of long power cuts sometimes it runs out of battery.There are also regular voltage fluctuations in mains power resulting in my inverter regulating it & then UPS doing some correction(aka click sound) many times during day so I thought of using UPS as an extra layer of protection/backup.I am thinking of buying a 600VA APC UPS if its batteries can last for 2-3 years & it can support my CX550 during powercut/switchover.

 

[gta5]

The thing is inverter is meant for whole house & because of long power cuts sometimes it runs out of battery.There are also regular voltage fluctuations in mains power resulting in my inverter regulating it & then UPS doing some correction(aka click sound) many times during day so I thought of using UPS as an extra layer of protection/backup.I am thinking of buying a 600VA APC UPS if its batteries can last for 2-3 years & it can support my CX550 during powercut/switchover.

If inverter runs out of battery , you will hardly get 10-15 minutes extra with UPS.. Which I assume is not going to be on a regular basis .. You can monitor when power has been gone for long and accordingly close PC when you feel inverter might give up..

With or without UPS you are going to be dependent on inverter either way so it will not affect backup time of inverter for whole house and other equipments

Regarding fluctuations , I don't think you have to worry about it ..
Unlike many other budget PSUs
Cx supports full input range from 100-240v
It should automatically handle fluctuations between 180-230v .. Below that your inverter might switch to battery mode itself in wide UPS mode.. Or maybe it's 160 depending your inverter support range in this mode

It is better you try this and see for a week how does it play out , Cx 550 without UPS directly connected to inverter.. If it is able to sustain the load + fluctuations then this is much better

I mentioned this point in PM regarding UPS-PSU , going with 600va means taking that same risk again , it may or may not work , so unless you have a pre- arrangement with dealer for returning in case it doesn't work , don't go for it .. At least look at 800va or some numeric,microtek to save cost higher VA models if you want to go for a UPS

 

[gta5]

I had this exact same problem few years back and again a few months ago. I used a Corsair HX650 PSU with APC 700VA UPS. It used to work fine when the system was idle or not playing any games but the system shut down/restarted when I was playing a game during the power cut. Manually switching off power supply didnt cause a restart.
Both the times this happened when it was close to my battery replacement dates. Since my UPS was already 6years old, I replaced it with a Numeric 1kva and haven't had any abrupt shutdowns or restarts. Hope this helps

Thanks for sharing your experience..

Did it used to restart or did it used to shutdown completely with long overload beep ? And what was your cpu / gpu ? Did you change PSU or gpu anytime?

Also you mentioned that this happened only close to battery replacement dates.. Before that when you used to play games your pc never shutdown/restarted even once during power cuts between those years when your battery was healthy ?

 

[dexterz]

^^Can you tell me how old were the APC ups batteries when this problem started(you said UPS was 6 years old) & how much the numeric 1kva costed you?

Batteries were 2 yrs old and the numeric cost 4k from dealer in Ritchie street

Sent from my ONEPLUS A5010 using Tapatalk

 

[dexterz]

Thanks for sharing your experience..

Did it used to restart or did it used to shutdown completely with long overload beep ? And what was your cpu / gpu ? Did you change PSU or gpu anytime?

Also you mentioned that this happened only close to battery replacement dates.. Before that when you used to play games your pc never shutdown/restarted even once during power cuts between those years when your battery was healthy ?

It has done both restart and long beep shutdown. I changed from hd 7850 to gtx1060. But restart happened with both gpu. I use i5 2500k and gtx1060 now. Dont remember it restarting when battery was healthy.

Sent from my ONEPLUS A5010 using Tapatalk

 

[sinhead]

But at high loads , primary capacitors would discharge faster , resulting in more inrush current on top of already high demanding main PC load

I have a seasonic 520w psu. Any idea, how much more will it draw above and beyond the 520W? upto 600w? 800VA ups fails to provide backup at full load.

 

[whitestar_999]

UPS actual power output is usually 60% of VA rating so for a 600VA UPS it is (0.6*600=360W) & for a 800VA UPS it is (0.6*800=480W). If your system is at full load above 480W then obviously your UPS will shut down(or UPS batteries are dying & unable to provide even a few seconds of 480W backup).

 

[chimera201]

Umm... I still think it's the holdup time. The inrush will trigger if the capacitor discharges and the capacitor keeping it's charge is called holdup! The holdup isn't enough compared to the UPS's transition time and the inrush/overload is happening as a side effect.

What is the FSP's exact model? We know the CX550 has like 12 ms holdup according to cybenetics.
Also I noticed the cheaper APC UPS has transfer time written as 10 ms 'typical'.
I checked a higher VA model and it has written it as 5ms typical, 10 ms 'maximum'. So the higher VA model also has better transfer time.
*www.apc.com/salestools/JGNY-96UETV/JGNY-96UETV_R0_EN.pdf

 

[whitestar_999]

FSP Saga II 400W.Also check out this thread by me on jonnyguru forums(currently at 99 replies!):
Facing a strange issue with Corsair CX550 - jonnyGURU Forums

 

[gta5]

Transfer time of ups is not fixed everytime, so they mention typical and maximum time..


Also hold up time for his load will be much longer .. If you take 12ms figure at 100% load . Then his load is 150 watts max

550/150 x 12 - that is more than 35ms easily for his config/system .. That's a lot.. It will not be exactly like calcultaion due to various factots but roughly similar , atleast easily far more than required >25ms

Hold up time is the least likely cause because of this reason

Inrush current is also there with fsp , but itsn't as high that it is overloading UPS

@whitestar_999 did you try running it on inverter at least 2-3 times ? To see if it restarts ?/overload


The second cause maybe batteries , which may not be able to power a higher power draw but fine for lower load with fsp

 

[chimera201]

21.6ms for FSP

*img.purch.com/o/aHR0cDovL21lZGlhLmJlc3RvZm1pY3JvLmNvbS9SL0IvMjYxNDc5L29yaWdpbmFsL2hvbGR1cF90aW1lLnBuZw==