Beware: Your CyberPower UPS with yellow glue inside could burn up??

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Beware: Your CyberPower UPS with yellow glue inside could burn up??

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I've just read this article on Neowin. As a fair few of us use these UPS's, is it a cause for worry???

The CP1350PFCLCD and CP1500PFCLCD, the rev 1 and rev 2 variants, seem to house this yellow glue inside them as the primary adhesive. While using yellow glue is a common practice in the electronics industry, often used in audio components, among others, it is said to become partially conductive as it gets to older brownish form. So essentially, any such product of yours that houses such an adhesive is potential fire hazard. But of course, it will also depend on the temperatures.

I'm trying to work out what CP1500PFCLCD variant I have.....?
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I have 5 units, all with same model number. Of the 5 I have three different types, based upon display backlight color, on/off button & LED, and battery access.

This reminds me of the yellow glue that Sony used to use for holding things to PCB’s in Broadcast equipment in the 1980’s/90’s. It became conductive and was famous for changing levels at test points, causing intermittent operations and video levels, that also varied with temperature! Tip-off was: it turned dark brown. It was a pain to remove as it was primarily used to hold down hybrid IC’s and filters that were easily damaged and $$$.

Can anyone give greater information via serial numbers of affected units? I know Sony eventually came out with a tech bulletin on serial numbers of boards with this issue.

I’d be willing to attempt a repair based on Sony Glue experiences if I knew which to look for, and post results on what was used, where, etc.
From the bit of thread reading I’ve done it looks if you run the UPSs at low load you reduce the risk and some guys out there say the UK models (or non-US) are not affected. Mine is used at very low load and is a UK model so I think I'll run it until the warranty runs out and then either find somebody who can put a new battery in my old APC unit(s) or spend and buy an EATON UPS.
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If they know it only follows V1 & V2 versions, they gotta know the serial numbers for them

Based on the Sony version of this problem, TIME: is the issue. The older, the more conductive. Just sitting there without power applied, and it got worse. Had to be removed to fix PCB.
Me would think that running at reduced workload just prolongs the issue to outside of warranty timeframe. That doesn’t help anyone at all, except the accountants of the company. If unit is rated at 1500VA, it Probably can run at higher than 1500VA— in order to be spec’d at 1500VA.

Get me the info, (serial numbers) and if any of my 5 are applicable I’ll disassemble them & document the symptom and come up with a solution! (Granted: the solution may involve using chemicals on components and PCB’s, repairing to the component level)
Ineed, but it looks like they are not acknowledging the issue (if there is one) so I can see no way to get the serial numbers from them.
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Ok watched video: 10:47 on video.
Yes, it is same locations Sony and others use glue. It’s used to quiet the switching supply caps running at switching frequencies’ sub harmonics. Seen it used on transformers and other type of caps too.

Yeah, it will be difficult to remove based upon those locations.

I can see why company doesn’t want to talk about it.

If I was gonna approach this, it would be unsolder caps to gain access to glue.. Remove glue.. replace caps with low ESR versions.. and use Silicone Glue to shock mount cap so it doesn’t start singing at switching supply sub harmonics.
The glue bonding down wires should not be an issue, as they have insulation.
Obviously a decent solder sucker system will be needed. This is not a job for solder pencil & solder wick unless you are exceptional at soldering PCB’s.
It’s a very time consuming, expensive (To get good low ESR Caps), job that has to be done 100% perfect. Or Else.

By the way, this is not something that would only be applied to 60 hz power (USA) locations. Unless they used an altogether different glue on European units.

PS: What Sony did:
They issued a Field Bulletin on this, indicating that a failure may occur, what board model, components that are involved, and where to find problem (pictorial and schematic).
And the fix is to remove cap, remove glue from PCB, replace cap, (sometimes with a revised cap value), and indicate where to use silicone glue to quiet the supply, but Sony would gladly sell the replacement/revised parts. But that got them off the hook: It was now up to you to fix it.
Next time I swap batteries in each, I’ll examine further and add to this thread. Seeing that I’m quite familiar with Sony’s issue, I’ll be able to determine how this issue will rate. In meantime if any serial numbers of affective units turn up—please post.
FYI on this old subject. One unit examined last year—Nothing bad.
I’m awaiting a used one, without batteries. Unknown vintage. I plan on disassembling it to examine boards etc, Before installing new batteries.
I’ll post what is found.
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CyberPower UPS showed up 3 days before Replacement Batteries...
Model: CP1500AVR Serial# CPAEP2001037
Board a different layout compared to Video of Ver1 Ver2 units... no indication of build date on components or labels, that I could see...
I'm finding glue, but not Yellow or Sony Tan Glue that turns dark and becomes conductive...
The Glue I'm finding is in few locations and is Gloss White Silicone Glue, like you'd use on your bathroom...
Also saw little gloss white silicon glue on interconnect on display board.
Comparing to videos posted, the use of glue on this unit is more controlled—less glue being used, than in videos.
Sony went to silicone glue (They used Clear) for dampening devices in Support & HV Areas.
Caps used are good 105C types, and not swollen.... good.
Only thing not included with UPS was the 1/3" spacer between batteries... Will have to come up with something, and Shipping tape will hold the battery pack together.... It awaits new batteries.... I don't see this type of glue being an issue at all!
I wish there was a date code somewhere. I assume that this is a fairly recent unit.
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So I asked CyberPower UPS Support if a serial number list exists of the yellow glue now that they switched to White Silicone Rubbeer for 1500VA units (I now have 6)....
and this is what Jayson L replied:
"CyberPower has thoroughly tested the rubber glue we use, and our results are aligned with industry information – meaning there is no danger of the UPS catching any unfortunate events or shorting out as a result of the glue"

As the Chat continued on, an I reported about the white silicone glue I found on the used unit, verses the Yellow glue reported to be conductive..... and passed along the serial number of used unit... (I plan on using as a spare, to cover future failures) ..he asked for my email address, and said he'd ask his support manager if a list by serial number exists. Did get an email, requesting serial numbers of other 5 units... Ongoing on multiple fronts! :)
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WOW! Methinks he got his hand slapped!
Before I could ask my Wife to get on her hands & knees to write down serial numbers……. (Knee replacement!) I get this email reply, making me think that he did in fact contact his supervisor on this for me!!!!

“Hello Jan Janowski:

I want to apologize as I mistakenly provided you with incorrect information, as I mentioned that we are still using the same rubber glue without enough information. But rest assured that CyberPower products are UL listed for safety and the rubber glue we use is also UL listed. Products from CyberPower have been tested and verified under the safety standard.

We thoroughly tested the rubber glue we use, and our results are aligned with industry information, which means there is no danger of the UPS catching any unfortunate events or shorting out as a result of the glue.

Regarding the serial numbers you mentioned, it's unfortunate that we can't disclose that information as it's for internal usage only.

Let us know if you have other concerns.

Best regards,
Technical Support Representative
Cyber Power Systems, Inc.”

I replied asking if he still wants my other 5 serial numbers……….

EDIT!! Immediately received this:

“Hello Jan Janowski:

Appreciate your quick response.

All the adhesives we use pass UL safety certifications and it's completely in compliance with national and international standards. Rest assured that all our products are safe.

I apologize for the inconvenience, you don't have to send the serial numbers anymore. Thank you.

Best regards,
Technical Support Representative
Cyber Power Systems, Inc.”

Well these do give us some useable information:
I would say that since I found white silicone glue on the hold down on display board, easily seen when opening up for battery removal…..
(Getting to main board involves complete disassembly), that on a battery swap, you could determine WHICH GLUE is being used on that UPS.


IF YOU FIND HARD YELLOW OR DARKER GLUE, You might have a concern….

In my case, the Spare, assuming used spare works with new batteries…. When they arrive….
I have to wait until my knee is better before doing anything!

Once I do have a spare, (and a knee that works), I will start examining and labeling the 5 other UPS’s from 2015-16
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12V9A Batts arrived/installed. Spare 1500VA tested with 2.4.8 PPP
Follow up tests next day to confirm system charges.... and another few passes with PPP Software testing with ~70% maximum load on system... Passed... Labeled: "Spare, New Batts 3-23, Silicone Glue" Total cost: $81.00
Ready For Service!
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Used Spare Cyberpower 1500VA
Unit (Unknown date)
Serial CPAFP2002959
Has white Silicone glue

Examined another Cyberpower 1500VA Unit: (2015-16)
Serial # CPAFP2002959
Has white Silicone Glue

Examined another Cyberpower 1500VA Unit: (2015-16)
Serial # CPAEU2005873
Has white Silicone Glue

Note: Not a Typo! 2 have SAME SERIAL NUMBERS! Other 3 as yet un-examined 1500VA UPS’s: 2 of 3 would definitely be 2015 bought units, 3rd would be 2016 bought unit. All 3 are on floor behind furniture, or in bottom of rack on shelf. One on 2nd floor up 15 steps.. and to determine glue front panel must be removed…. on each unit: outside of my present ‘range’. So, I’ll update this thread with those last 3 UPS’s data, in a few months. Mark this thread: Ongoing!

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