UPS Electrical Failure - Teardown and Analysis!

hi everyone welcome to Mr Carlson's lab never a dull moment here this APC back UPS failed in a pretty spectacular way now I have a bunch of these things all the other ones were fine but this one here decided to I guess it sounded like it was arc welding inside so maybe it wanted to change from a UPS to an arc welder I don't know but it sounded pretty violent inside and while the alarm was screaming on this thing and I'm holding this thing to shut it off it was just making horrible noises and at that point I just took all the other ones out of service I have a bunch of these they're all the same so something very interesting about these I bought these things oh about a year year or so ago and they've been through a total of two power failures so technically one power failure because this last one didn't count if because that's when it failed but it has this somewhat of a receipt-like looking thing on the side and it says quality assurance test and it says revision looks like one zero one three and there's just a whole bunch of uh past this has passed on all these different tests and then it was signed off on the bottom here so I don't know if this was a recall or something like that uh all the other ones that I purchased had the same thing on it and um yeah so I don't know what this is maybe they were worked on or maybe this was a revision that was done later or maybe they just taped the revision onto it I really don't know what's going on but I found this odd so I left it on the side of it these things aren't seen so I really don't care how it looks you know they just they're just there to do a job and this one did not do its job so uh sounded pretty violent so am I going to reverse engineer this thing and try and fix it and maybe maybe fix their design flaw or whatever now I'm not going to bother with it I'm not going to waste my time on this thing I already have replaced these things with brand new a different brand uh brand brand new units put them back into service and everything is fine hopefully they don't do the same thing and um so this one will just tear down take a look inside see what failed see if we can see any burn marks and what was arcing and sparking inside maybe it'll do it again who knows so we'll take a look inside and tear this thing down take a look inside this uh APC UPS so this is the battery door so when I purchased this one battery clip is unhooked and it tells you that you have to attach the battery at the time so I've taken the battery out obviously because I wouldn't leave batteries in any of these things even sitting after I heard this thing so everything is disconnected so what I'll do is I get a battery I'll attach a battery to this thing I'll plug it in like it was plugged in and we'll see if we can make it do anything and uh maybe it'll make some noises again who knows what's going to happen so uh at that point uh we'll open the thing up and see if we can look for any burn marks all right here's the battery nice big heavy battery so they're in series so it's about uh these are 12 volt batteries each right so I think when I read it last they're charged up pretty good it was about 27 volts or something across the both of them so let's attach the positive terminal look at this stiff wires over here let's attach this I think it was attached like this before it is and let's attach the negative terminal here I have a pair of Clippers here by the way just in case one of these was to latch and I couldn't look at that nice big spark in there eh let's see if I can get that all like so slipping under the heat shrink there okay it is hooked up so what I'll do is uh plug this thing in to the bench Supply all right Clippers right here just in case something goes wrong let's see what happens here we go that's just screaming now she's gonna shut off for me not even shutting off look at that oh did that time okay so it's not doing anything okay so let's unplug it and see what it does completely unplugged again here we go well different failure point so that's what it did it was just sitting here screaming with a failure point and sounding like the thing was just arc welding inside now the arc welding has stopped so obviously probably burnt something up or it shut something down inside so it can't continue so uh yeah those actually come off pretty easy which is nice so now let's disassemble this thing so it looks like it has some screws on the inside here and some screws on the back so I'll get those screws out and let's take a look at the inside all right I removed every screw I can see on this well I can see something inside I see some circuitry that is glued together or what's going on here looks like it might be clipped together I'm not really quite sure it seems like it wants to come apart here I can't see any other screws so let's uh probably just snap together I don't know if they've plastic welded anything here at all feels like it's pretty solid all right see what they've done in there actually I do have a flashlight close to me what are the odds you see inside there what is it yeah the whole thing is just clipped together I'm not seeing any burn marks in here yet you can see down in there in there any burn marks in there yet so all right I'll wrestle with the case here for a few more moments I'll spare you from that and see if I can get the actual case important well that wasn't so incredibly bad to get apart there's a bunch of screws hiding under the face of the unit so if there's a little area at the bottom right down here that you can basically pull this off the whole face comes off and there's some screws hiding in there other than that it just kind of snaps together so yeah a nice Transformer in this thing so nice little inverter Supply going on in here and I can't see any type of burning inside so maybe it's on the back side of the board so in order to get this out it looks like there is a bunch of screws there's a screw up in the corner up here so let's see if there is any any burning on the back side here so if there's one there there's probably one at the other end of the board here isn't there there is all right is that about it let's see if it'll let go of the board boy that's in there wow remove some of the wiring out of the way there is another screw I see another screw right here still feels like it's a bit solid or maybe not well yeah I think there's one here they fastened this top one up here as well and there it is doesn't look like any arcing on there wow for something that sounded so incredibly violent it's doing a very good job of hiding it I wonder where that nasty sound is coming from couldn't be this Transformer wasn't arcing inside or something foreign look around carefully here and I'll be back when I find burn marks I cannot find any burning on this board whatsoever and it was such a violent arcing noise it has to be this thing it has to be arcing windings inside this thing it does have a little bit of an odd smell to it and you know there is a little bit of I don't know if you can see that a little bit of discoloring up here so I don't know if that is it but if it is our kings that is the little bit Brown there if you can see that under there so it might be actually inside this Transformer may have been arcing inside here and of course if that would just cause failure period all right so I've got the Transformer unhooked now very simple it just unclips and then you do these two screws at the top of these two sinks here so I have this on continuity because this is going to be all low ohms anyways I'll put this in here and just before we go about doing any type of a leakage test we'll just test for continuity no problems there let's go to this one here interesting okay let's see grab my flashlight here again let's see interesting all right well it looks like there's an open connection here in the Transformer because that's definitely doing that so let's open this up and see what we find inside see if we can see inside here see anything at all and out of the way stuck to paper and we can get rid of the paper here let's see what happens that definitely doesn't feel like any type of connection all right let's see yeah that's definitely was making the arcing and sparking there it's pretty dark so the Transformer failed what an odd thing to fail Amy this is the most robust piece out of anything right oh we can see that look it just disconnected from that that's all so technically this is still salvageable but it does look like it uh disconnected I'm going to go take a look at that under the microscope and uh see if this is actually leading in or if this is what's going on with us here I'll be right back well you can definitely see the failure point is that wire you can see the burn mark on the paper here and there's two windings here and the windings are very soft like these windings are so soft for a piece of copper that's unheard of and it makes me wonder is that even copper and if so like you mean what else would it be aluminum windings but if it was aluminum that's a solar connection obviously that didn't take right you can actually see where it's burnt up in there right is this actually aluminum no couldn't be okay I managed to pull a little bit of the wiring out of the Transformer here you can see I've cut a little piece off here I'll cut another little piece off here that's not looking like copper inside is it I think these are aluminum they tried to solder to aluminum windings all right definitely soldering iron time now let's see if this thing takes solder at all right what a surprise let's try this again you know at least make the attempt crimp it or something so you can see I'm touching touching it completely that stinks wow amazing and I thought that felt too soft to be copper that just if this is so this almost feels like solder itself it's that pliable right because it's just soft aluminum wow I'll go grab a piece of copper for comparison and I'll show you so here's a piece of copper gauge isn't exactly the same but you can see if he's a copper for comparison for color comparison makes me wonder about the other connection here how did that hold up let's see pack this out so you can see what's going on the glue that holds these wires is better than the actual connections themselves okay so here's another one okay so look at this oh man so they have a piece of soldered wire that they folded and pinched over top of the uh aluminum open up the mechanical crimp and find out what's going on this up just like so of course you know that's what it is right there yeah so you can see how it's just you can see here how it's just they've wrapped the solder over top of the wire see that there it's just pressed in there well anyways we know the failure point in this thing so it looks like a really nice looking Transformer but uh what's inside is something quite a bit different so that's the failure Point that's what was sounding so nasty as it was arcing out and they're buzzing and sparking inside the Transformer Transformer went away if you're enjoying my videos don't forget to hit the Subscribe button and tap the Bell symbol if you want to be notified as soon as I post a brand new video there'll be lots of tear downs and Restorations there'll be lots of repairs and circuitry design all sorts of great stuff on this channel the next episode involving this RCA cr88 Communications receiver is just about ready as well so just another reason to subscribe and tap the Bell so that you're notified if you're interested in taking your electronics knowledge to the next level and learning electronics in a very different and effective way and gaining access to many of my personal electronic inventions and Designs you're definitely going to want to check out my ongoing Electronics course on patreon I'll put the link just below the video's description under the show more Tab and I'll pin the link at the top of the 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Channel: Mr Carlson's Lab

Views: 147,315

Keywords: Power supply repair, failure analysis, test equipment, Mr Carlson's videos, electronics course, learn electronics, fix electronics, electrical engineering, fix circuits, repair circuits, circuitry repair, APC UPS, UPS teardown, electronic teardown, equipment teardown, how to test circuits, Power supply teardown, Mr Carlson's electronic course, Paul's electronic videos, electronics teacher

Id: dIEM2bG8mOQ

Length: 18min 10sec (1090 seconds)

Published: Fri Feb 03 2023