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Seasonic S12II 520W, NO backup on APC UPS

10 posts · originally from https://geek.digit.in/community/threads/seasonic-s12ii-520w-no-backup-on-apc-ups.191345/

V
virajkin Original post #1
May 10, 2015 at 9:16 PM
Hi everyone

For past few days I face an issue with my APC 1100 VA UPS backup i.e when the mains AC power goes off the UPS doesn't give any backup and directly goes OFF giving a long beep. Earlier I thought its a UPS issue so to cross check, I got a friends Numeric 1KVA UPS but here also I faced same problem. I tested my UPS with friends system. He is having a Corsair GS 600 PSU. My UPS works perfectly fine with his system


So I found that there is a issue with my Seasonic 520W PSU so its not giving UPS backup and trips off. After searching on internet also found that few people have faced same issue like this

Kindly give your suggestions. Should I do RMA of my PSU from Tirupati Enterprises?
bssunilreddy
bssunilreddy #2
May 11, 2015 at 8:13 AM
Yes try to RMA your PSU then test it again after RMAing ok.
S
sinhead #3
May 15, 2015 at 6:16 PM
I have the same PSU and It doesn't give back up on my microtek ups.

From what I read here and other forums - some PSUs don't handle the power generated by a UPS battery since it is different from the power that we get from the mains.

activePfc_ upsCcompatb.JPG


But anyway, I too am looking for a solution, hope your thread leads me to it. Waiting for suggestion by experts.
avinandan012
avinandan012 #4
May 15, 2015 at 7:24 PM
that PSU have problem with working with non-sinewave output. IMO RMA wont solve your problem.
V
virajkin #5
May 16, 2015 at 5:49 PM
avinandan012 said:
that PSU have problem with working with non-sinewave output. IMO RMA wont solve your problem.
Click to expand...
But That PSU worked for about 6 months properly without any issues.
chimera201
chimera201 #6
May 16, 2015 at 8:10 PM
This might be a funny question but did you check the wall socket for power? Did you check the PSU directly connected to the wall socket?
rijinpk1
rijinpk1 #7
May 16, 2015 at 8:33 PM
^^ since he mentioned 'when the mains AC power goes off the UPS doesn't give any backup', his pc should be working perfectly fine when the AC power is on!

seasonic higher end units infact has problems with non-pure sine wave upses. but the capacity of the ups accounts as well. what i think is your psu's active pfc circuit is malfunctioning/damaged. you may better rma your psu.
do you use your pc on battery for a long time? that is not good for active pfc psus, especially seasonic wont love that!
V
virajkin #8
May 17, 2015 at 7:02 AM
rijinpk1 said:
^^ since he mentioned 'when the mains AC power goes off the UPS doesn't give any backup', his pc should be working perfectly fine when the AC power is on!

seasonic higher end units infact has problems with non-pure sine wave upses. but the capacity of the ups accounts as well. what i think is your psu's active pfc circuit is malfunctioning/damaged. you may better rma your psu.
do you use your pc on battery for a long time? that is not good for active pfc psus, especially seasonic wont love that!
Click to expand...

Thanks for the reply, BTW I have sent my PSU for RMA at Tirupati Kolkata office. I dont use the UPS for long time on Battery, as main power goes i Immediately Shut down the systm in 2 minutes
U
uts7 #9
Jun 17, 2015 at 9:23 AM
I have a seasonic m12ii 620.need suggestions for a pure sine wave ups.
R
REDHOTIRON2004 #10
Jun 17, 2015 at 4:56 PM
virajkin said:
Thanks for the reply, BTW I have sent my PSU for RMA at Tirupati Kolkata office. I dont use the UPS for long time on Battery, as main power goes i Immediately Shut down the systm in 2 minutes
Click to expand...

Any updates whether the problem is solved or not?