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MOSFETS BLEW UP in my UPS-CyberPower-1500
Posted: Sat Jan 15, 2022 1:45 pm
by bob195558
Hi Everyone,
Last Thursday my CP1500AVRLCDa CyberPower battery backup
blew up with flashes of fire and smoke coming from the upper vents.
It was impressive to see and my desktop computer and monitor shut off immediately.
I opened the unit up and easily could see that several of the
SM6002N diodes have blown apart.
I want to repair it, do you think if I replace the 8 diodes it may work again ?
- Diodes Blew apart_a.jpg (151.04 KiB) Viewed 12430 times
- Diodes Blew apart_d.jpg (72.11 KiB) Viewed 12430 times
- Diodes Blew apart_e.jpg (176.21 KiB) Viewed 12430 times
Re: Diodes Blew Up CyberPower 1500
Posted: Sat Jan 15, 2022 7:50 pm
by bob195558
Hi,
Anyone have an idea to what could be the cause for the diodes to blow apart ?
CyberPower 1500VA AVR Model: CP1500AVRLCDa
I have found some replacement
SM6002N diodes and was thinking that it may be a good idea to replace the relays too.
As I was thinking, if a relay stuck together it may have caused a big short, but I am not sure what the cause is.
Relay:
ONC CHUAN
812H-1C-C F24V-DC
(SA)C US (CQC) 7A 250V
16A 277VAC 12A 250VAC T85
20A 125VAC C1728
- Relay CyberPower 1500_a.jpg (125.38 KiB) Viewed 12418 times
Also I did a search for a replacement main board: 2PD-0000338-00G
. M17J099197
I was not able to find any.
- CyberPower 1500VA AVR Mainboard_.jpg (154.88 KiB) Viewed 12418 times
- CyberPower 1500VA AVR Mainboard_b.jpg (188.93 KiB) Viewed 12418 times
Re: Diodes Blew Up CyberPower 1500
Posted: Sat Jan 15, 2022 10:47 pm
by Kilrah
SM6002Ns are MOSFETS, not diodes.
All 8 may not be identical, so be sure to check the type of the ones on the back.
Could be that one failing took the others, but could also be a fault on the transformer or a serious instantaneous overload on the output. Does the PC / anything else that was connected to it work?
Check for heat/burn marks on everything including the board traces. Pics are too tiny to see much.
Re: Diodes Blew Up CyberPower 1500
Posted: Sat Jan 15, 2022 11:45 pm
by bob195558
Hi Kilrah,
Thank you for your reply.
When the MOSFETS were blowing,
they seemed to be blowing one after the other, very quickly with loud noises, fire and some smoke.
Computer and monitor stopped running and I had another UPS,
which I swapped in and all started up as if nothing had happened.
So that is and was good, only the failed UPS itself has seemed to have failed to what I have observed so far.
I am leaning toward your first suggestion “that one failing took the others” out.
I will next take the main board out and check it over good
and let you know what I may find.
Also what I can do when posting pictures, I can post each picture two times one with the low pixels (740) which will show
and the other, a link with High Pixels, which then can be zoom in to view small areas with better details.
Thank you for you help.
Re: MOSFETS BLEW UP in my UPS-CyberPower-1500
Posted: Sun Jan 16, 2022 2:03 am
by bob195558
Looking over the mainboard,
I did not see any other thing that may be heat/burn and traces looked good.
Some manufacturing stuff looks to be a little dodgy to me, but that is what that is.
There is some explosion debris on the mainboard.
You will need to download each of the higher Pixels pictures to be able to view them more closely:
- UPS1500AVR MainBoard_aa.jpg (194.66 KiB) Viewed 12406 times
- UPS1500AVR MainBoard_b1b.jpg (268.59 KiB) Viewed 12406 times
- UPS1500AVR MainBoard_b2b.jpg (271.11 KiB) Viewed 12406 times
In the pic b2 you can see where the solder for the MOSFETS has melted.
- UPS1500AVR SubBoard_dd.jpg (207.21 KiB) Viewed 12406 times
- UPS1500AVR SubBoard_cc.jpg (213.96 KiB) Viewed 12406 times
Fuses checkout OK.
- UPS1500AVR MainBoard_ff.jpg (100 KiB) Viewed 12406 times
- UPS1500AVR MainBoard_ee.jpg (195.34 KiB) Viewed 12406 times
So next I think I need to unsolder the 4 outer MOSFETS heat-sink group
and make sure they are the same as the inner group.
Maybe tomorrow I can take some more pics with the natural sun light, as the pics would have a lot better color and less shadows.
Re: MOSFETS BLEW UP in my UPS-CyberPower-1500
Posted: Sun Jan 16, 2022 1:31 pm
by bob195558
Here is a much better pic of PC backside where the SM6002N mosfets are located.
Click on the link to open the pic and you can zoom in for a better view too.
I am having some difficulty finding new SM6002N mosfets.
Is there a mosfet that will work in its place ?
Re: MOSFETS BLEW UP in my UPS-CyberPower-1500
Posted: Mon Jan 17, 2022 12:04 pm
by bob195558
Update
Using Chip-Quick to help removed the two inside Heat-Sinks all 8 Mosfets are the same. 
- Mosfets SM6002N Blown_aa.jpg (190.66 KiB) Viewed 12352 times
I have only been able to find used SM6002N MOSFETS,
which would be a cost of about $40 ($30 would be shipping).
I am not thinking this would be a good thing to do.
So is there a different Mosfet that I can use in the place of the SM6002N ?
Re: MOSFETS BLEW UP in my UPS-CyberPower-1500
Posted: Tue Jan 18, 2022 1:41 pm
by bob195558
Search for MOSFET:
SM6002N
WT49A
Have found this
- SM6002N mosfet_express_technology_com_aa.jpg (81.3 KiB) Viewed 12326 times
Re: MOSFETS BLEW UP in my UPS-CyberPower-1500
Posted: Fri Feb 11, 2022 11:04 pm
by jhsa
I wonder if that transformer committed suicide and took the Mosfets with it?? Just guessing.
hard to see on the pictures but the soldering on the mosfets pins doesn't look very good.
João
Re: MOSFETS BLEW UP in my UPS-CyberPower-1500
Posted: Sat Feb 12, 2022 12:15 am
by bob195558
Hi João,
Yes, I also have been thinking something else may have been the cause
and because the MOSFETs are difficulty to find and with the cost.
If they were to fail again, it may be better to use the cost toward a new CyberPower-1500.
I was able to find a new CyberPower-1500 for $160.06 delivered.
If I could find 8 MOSFET’s for about $20 delivered, I would think about trying to fix it.
I have all the parts in a box, set aside for now.