APC UPS, now with aluminum wire

[coppercone2]

damn it sounds like something happened to that wire it should not be so fragile. Its fragile but you should be able to loop it

does it get oxidized and stiff over time that makes it unable to bend?

[SeanB]

Aluminium work hardens a lot more than copper does, and yes with time you get intermetallic corrosion as well, which creates thin layers of insulating oxide through the cable. Thicker cables this takes a lot longer. You will find the reason the wire is copper coated before insulation in motors and transformers is to both allow it to be soldered, and also to provide a barrier to oxygen penetrating, though I have seen wire down to 36SWG be copper coated aluminium now, before it was only things that were 18SWG or lower that were CCA, but now you see very thin CCA wire, especially in things like network cable, where you get 7 strands in 22AWG wire in the sheath, and those do sort of hold up, though they do not solder at all well, and will hold up in a crimp for a while. Gel filled Scotchloks though do work well on them.

[coppercone2]

its interesting because I heard that with air plane parts if they are anodized they will fracture after enough fatigue rather then just bending (reason for alodine and paint instead of anodizing airplanes). Its kind of like wood in that regard when it gets old it seems like. Not sure if the natural oxidation would ever compare to the anodizing process though for that effect to occur. So its not like the hard surface just cracks off like I would think it does but it makes the material crack suddenly.

kind of wonder if you made a bare aluminum plane that was exposed to the air for long enough would it turn brittle like that. I wonder how many years it would take.

[fmashockie]

This seems to be a fairly common issue with these BR1500MS pure sine-wave models.  They are probably one of the main offerings by APC is the ~$200USD price range.  My work has a few APC UPSs to power some of our equipment that we cannot afford to lose data on.  We had a BR1500MS in operation for ~4 years (probably a little longer than the warranty) and it all the sudden started smoking and beeping.  I took it out of service (I am the lab equipment engineer for my work) and it sat in my junk pile for a while.  During down time I would take a stab at fixing it, but it just kept blowing the inverter MOSFETs.  I had suspected the transformer, but it passed continutity test and hooking up to my variac, it was able to deliver the correct voltage.  Then I saw this video from Dr. Carlson's lab.  I took a look at the transformer tap connections and mine looked pretty sturdy unlike his.  I ended up acquiring a HI-POT tester for a different project and I hooked up the transformer to it - it failed immediately!! Also, grabbed a transformer on eBay from a similar model and now the UPS works just fine!  He's right though - typically the transformer should be one of the most robust components in a unit like this.  So it makes troubleshooting one of these when they throw errors (like F02, F04, or F06) a real pain in the ass if you are unaware.  Here's a video I posted on youtube HI-POT testing two different APC transformers 1) the BR1500MS and 2) BR1500G

[fmashockie]

Another follow-up to this topic.  My work got in a couple of these APC UPS BR1000MS models.  They are the pure sine-wave model also called the UPS back-up Pro.  It is one APC's most well known offerings and it's likely one of the first UPSs to pop up on Amazon if you search 'UPS'.  They are the exact same type that Dr. Carlson shows in his video.  Anyway, I decided to HI-POT test the large AVR/inverter transformer when it is brand new.  It fails miserably!! I can barely get it up to ~400-500VAC.  This is terrible when you consider the formula for HI-POT testing which is V_t = (2V_w + 1000) where V_t = test voltage and V_w = working voltage.  The max working voltage for this transformer is ~120VAC.  So test voltage for this transformer should be ~1200VAC and it should be able to withstand that for a few secs.  It cannot get even close to that!! And again, this is brand new right out of the box!! Here's a video I did showing the test below.

Now I've also tested the APC UPS BR1500G AVR transformers and they seem to be built much better.  They will pass a HI-POT test at ~1200VAC.  So if you ever have one of these BR MS models and want to fix it, you can grab one of these BR1500G transformers on eBay (I've seen them go for $20 used).  You'll just need to replace the primary side lead wires to a thicker gauge and of course change the terminals to ring or fork style.  I've done this repair on my own BR MS models and it works great!!  If you have one of these BR MS models I would recommend doing this because this transformer will likely fail at some point and when it does (due to internal breakdown/shorting btw windings) it will draw massive amount of current and blow one or more of the inverter MOSFETs.  This can happen in a very violent manner and could cause a fire.

Also, I know Dr. Carlson complains about the transformer winding being aluminum, but a lot of transformers use aluminum windings and they have no problems whatsoever.  These are likely just made poorly with inefficient insulation.  I'll have to cut one open to see how it looks inside!  Hope this helps someone!

[jrmymllr]

Another follow-up to this topic.  My work got in a couple of these APC UPS BR1000MS models.  They are the pure sine-wave model also called the UPS back-up Pro.  It is one APC's most well known offerings and it's likely one of the first UPSs to pop up on Amazon if you search 'UPS'.  They are the exact same type that Dr. Carlson shows in his video.  Anyway, I decided to HI-POT test the large AVR/inverter transformer when it is brand new.  It fails miserably!! I can barely get it up to ~400-500VAC.  This is terrible when you consider the formula for HI-POT testing which is V_t = (2V_w + 1000) where V_t = test voltage and V_w = working voltage.  The max working voltage for this transformer is ~120VAC.  So test voltage for this transformer should be ~1200VAC and it should be able to withstand that for a few secs.  It cannot get even close to that!! And again, this is brand new right out of the box!! Here's a video I did showing the test below.

Now I've also tested the APC UPS BR1500G AVR transformers and they seem to be built much better.  They will pass a HI-POT test at ~1200VAC.  So if you ever have one of these BR MS models and want to fix it, you can grab one of these BR1500G transformers on eBay (I've seen them go for $20 used).  You'll just need to replace the primary side lead wires to a thicker gauge and of course change the terminals to ring or fork style.  I've done this repair on my own BR MS models and it works great!!  If you have one of these BR MS models I would recommend doing this because this transformer will likely fail at some point and when it does (due to internal breakdown/shorting btw windings) it will draw massive amount of current and blow one or more of the inverter MOSFETs.  This can happen in a very violent manner and could cause a fire.

Also, I know Dr. Carlson complains about the transformer winding being aluminum, but a lot of transformers use aluminum windings and they have no problems whatsoever.  These are likely just made poorly with inefficient insulation.  I'll have to cut one open to see how it looks inside!  Hope this helps someone!

I just bought a BX1500M and then found all these complaints about newer APC UPSs failing because of the transformer. Needless to say it makes me a little uneasy. I have 3 older consumer grade APC units that are at least 19 years old and they just keep going. Plus a 25 year old Tripp Lite, again a consumer grade unit in a plastic chassis, that still works. I have serious doubts about the longevity of the new one.

Interesting how the BR1500G transformers seem to be better. I wonder what the BX1500M uses.

[fmashockie]

I'm not an expert on this by any means and I have only sampled a small portion of these UPSs, but in my investigations, this problem with the transformers seems to mainly affect the pure sine wave models (economy priced) like the BRxxxMS units (1000, 1500VA).  So you might be in the clear.  The BX1500M is a simulated sine-wave unit similar to the BR1500G.

I don't know why the BR1500G (another simulated sine wave unit) has transformers that seem to be better quality.  But the BR1500MSs that I have repaired with BR1500G transformers are still going strong without issue.

The simulated sine wave units are not without their faults though.  For example, I have a BR1500G that developed an F06 error out of nowhere.  The F06 error indicates 'relay welding' which means a relay is failing to open or close.  There are 7 mechanical relays in the BR1500G.  In my case, both the buck and boost relays for the AVR function were not working properly.  This was due to a failed microcontroller.  I did a thread on repairing this by replacing the micro.  I uploaded the firmware there as well for anyone who needs it. 
https://www.eevblog.com/forum/repair/repair-help-for-apc-ups-br1500g-f06-error/msg5019466/#msg5019466

[jrmymllr]

I'm not an expert on this by any means and I have only sampled a small portion of these UPSs, but in my investigations, this problem with the transformers seems to mainly affect the pure sine wave models (economy priced) like the BRxxxMS units (1000, 1500VA).  So you might be in the clear.  The BX1500M is a simulated sine-wave unit similar to the BR1500G.

I don't know why the BR1500G (another simulated sine wave unit) has transformers that seem to be better quality.  But the BR1500MSs that I have repaired with BR1500G transformers are still going strong without issue.

The simulated sine wave units are not without their faults though.  For example, I have a BR1500G that developed an F06 error out of nowhere.  The F06 error indicates 'relay welding' which means a relay is failing to open or close.  There are 7 mechanical relays in the BR1500G.  In my case, both the buck and boost relays for the AVR function were not working properly.  This was due to a failed microcontroller.  I did a thread on repairing this by replacing the micro.  I uploaded the firmware there as well for anyone who needs it. 
https://www.eevblog.com/forum/repair/repair-help-for-apc-ups-br1500g-f06-error/msg5019466/#msg5019466

I am very curious if my BX uses this crappy soldering and will call APC next week. It's likely they won't give me a straight answer for several reasons, at which point I have another plan.

How old was the BR1500 when it failed? And I'm shocked you were able to read the code off that micro! I assumed it would be protected since it's so easy to set that bit.

I really wish I knew what UPSs are built well. The expensive ones are probably good, and I read a lot of recommendations for Eaton.

[fmashockie]

It is not so much the soldering in my opinion.  While yes, Dr. Carlson did find that on his unit, on the ones I have encountered, it appears to be something internal that causes them to fail Hi-POT testing.  The connections to the transformer are easy enough to check/fix - just recrimp them.

Yes I was quite surprised as well that the micro was not protected!  But my BR1500G is also still going strong after that repair.  It has to be ~5 years old.  I definitely recommend replacing the batteries of these units on a scheduled basis (every couple years or so).

[jrmymllr]

It is not so much the soldering in my opinion.  While yes, Dr. Carlson did find that on his unit, on the ones I have encountered, it appears to be something internal that causes them to fail Hi-POT testing.  The connections to the transformer are easy enough to check/fix - just recrimp them.

Yes I was quite surprised as well that the micro was not protected!  But my BR1500G is also still going strong after that repair.  It has to be ~5 years old.  I definitely recommend replacing the batteries of these units on a scheduled basis (every couple years or so).

The Hi-pot failures are something else, yes. But the fact that APC accepted these transformers and used them in production is simply negligent. That goes beyond a design error, or even cost cutting IMHO.

[coppice]

So were they relying on a crimp to connect to the CCA wire, or were they relying on the copper coating being a suitable layer to solder to? There is nothing wrong with CCA wound transformers, but this seems a very dodgy way to terminate them. With the windings brought out to a termination strip, with robust aiuminium to non-aluminium connections on the strip, it could have been perfectly good transformer. Even with a copper wound transformer I worry about these single strand to insulated stranded transitions taking place under a bit of yellow tape. They never look very robust.

[johansen]

So were they relying on a crimp to connect to the CCA wire, or were they relying on the copper coating being a suitable layer to solder to? There is nothing wrong with CCA wound transformers, but this seems a very dodgy way to terminate them. With the windings brought out to a termination strip, with robust aiuminium to non-aluminium connections on the strip, it could have been perfectly good transformer. Even with a copper wound transformer I worry about these single strand to insulated stranded transitions taking place under a bit of yellow tape. They never look very robust.

I dont know what they are doing but heat pump manuf and microwave oven manufs have been soldering aluminum wound emi chokes to circuit boards for 15 years now.

[fmashockie]

So were they relying on a crimp to connect to the CCA wire, or were they relying on the copper coating being a suitable layer to solder to? There is nothing wrong with CCA wound transformers, but this seems a very dodgy way to terminate them. With the windings brought out to a termination strip, with robust aiuminium to non-aluminium connections on the strip, it could have been perfectly good transformer. Even with a copper wound transformer I worry about these single strand to insulated stranded transitions taking place under a bit of yellow tape. They never look very robust.

I disagree.  The problem with these transformers aren't just bad connections.  These transformers clearly have multiple issues.  If you watch my videos where I HI-POT test two separate transformers from the BR1500MS models (one brand new, the other ~5 years old), they both fail miserably (my comments are above).  And neither of them had poor connections to the lead wires like Dr. Carlson's.  My point is, Dr. Carlson misses the mark with his explanation.  Al-winded transformers are not inherently bad like he tries to claim.  There are many examples of Al-winded transformers that work just fine.  Sometimes they are more advantegous to use than Cu depending on the application.

[lunix]

FWIW: I bought a Cyberpower pure-sine wave UPS (1500VA) from Costco.  I plugged it in, and nothing happened.  I moved the line cord and heard relays clicking.  I left it plugged in (like a dummy would) for a few hours, even though it said it was 100% charged from the outset.  I turned it on, and when I lifted the front to check the display, I heard the relays again.  And I brought it back to the store (though purchased online), and bought another one.  That one had the power plug slightly smashed, but I bent the prongs back and it works fine.

I guess I am going to have to start paying $400-$500 for a better brand.  After watching these videos, I will never trust APC.