DR #1 - PC Power Supply Troubleshooting and Repair

everyone tonight I'm gonna be looking at this Apollo uninterruptible switching power supply it's an industrial power supply pulled from an industrial computer it's an Apollo Auto AUP - X - 300 it is definitely only partially functional I just plugged it in here and the fan kicked on for about two seconds and then it kicked back off the only thing I have on this is my standby supply voltage which should always be present with the incoming voltage that's going to be five volts from our purple connector here so second pin from the right here that's our standby voltage you'll see I have this jumper tout here that jumper is to turn on the supply so I have the green pin which is our power supply on jumper to the black pin which is ground that should enable the remainder of the outputs on this power supply which there are several outputs on this supply as you can see right here plus twelve minus five minus twelve plus five plus three point three and then here's my plus five standby so +5 V SB is voltage standby standby voltage so I should have all these outputs here when I jumper this pin and I'm not getting any other than the standby voltage which I can show you now so if I go to ground and of course you can't see the pins with my hand in the way but ground and the standby pin is five point one okay and then I do get the five volts if I move remove the jumper I get the five volts at the power supply on pin which is good that that pin should be about five volts as well and when it's pulled to ground which is what I was doing with the jumper it should enable the the remainder of the outputs and so it's not doing that so tonight I'm gonna be digging and opening this thing up and trying to figure out why the power supply is not being enabled so this is my first video doing something like this with electronics repair my background is I do have a lot of electronics repair under my belt I work in the semiconductor industry so I'm constantly exposed to different electronics just systems a lot of different advanced troubleshooting methods and tactics that I use in my day-to-day jobs so I'll be doing a lot more videos like this with malfunctioning electronic equipment TVs more power supplies such as this not necessarily industrial or not necessarily switch mode but also linear as well sound systems you know whatever I can get my hands on that's not working I'm gonna try and fix it so tonight I'm gonna tackle this power supply here and as I said I'll be doing a lot more videos like this in the future if you have a piece of electronic equipment that's malfunctioning and you want to send it to me in most cases I'll take a look at it and I'll repair it for free other than parts so if you want to send me something to repair such as a power supply you know like I said speakers or sound systems anything really electronic send me a note on my channel and I'll get back to you with whether or not you know it's something I'd be interested in whether or not I could do it especially for free right what do you have to lose - the shipping so please let me know and so now I'm gonna get after it get inside and we'll take a look all right so I have the cover off the supply what you're seeing here is the top board of the supply this is a two board supply so if you see this top board I'll flip to the side so you can get a better view power is coming in here through this connector comes into this top board through this connector right here so we have our two input wires to the board right here this is our main power supply board so you can see it comes in here and you know I'll take this board off in a minute and we can look at the board see all the components on there but basically you have your main input power supply here so you have your main transformer here you'll have filtering caps and directive bridge rectifier as well and then and then from this board you have a connector right here it's a little tricky to see but there's a connector right here you can see the brown and blue this connector brings the AC voltage from this board down to this bottom board this bottom board as you can see by all of these different colored wires is responsible for our DC outputs so our 5 volts 12 volts 3.3 volts etc I can also see you probably can't see it I'll try and help you I'm not plugged into the wall by the way I am plugged in here but I'm not plugged into the wall so I'm not manipulating this with live power but so they're two wires down here purple and green and that's leading from this bottom board as well which is our 5 volt standby and our 5 volt power supply on wires so I know that our outputs are coming from here and that also means that we're getting voltage down to this board we're getting voltage from this board down to this board because we do have 5 volt standby and 5 volt power supply on the question is why is that 5 volts power supply on when dropped to ground why does that not enable the outputs so I'm gonna plug this in quick and let's see if that fan does does what I says said it does guessing as it did last time it's gonna turn on for a second or two and then it's gonna drop out so that it's implying that would imply that the power supply on pin is working momentarily it is enabling the output and then dropping off for some reason so let's see if it does that I'm gonna plug it in right now would you look at that it's on I don't know if you can hear that but the fan is on and I'm gonna guess that now we have output of course Oh oh boy I'm not sure what happened there all I did was lift this connector up a little bit and you can see I pulled this out but I lifted this connector and you could hear the fan start to turn off and on and off and on so I thought it was maybe the pins were making good contact but I receded it without any luck try moving it around again so I think I mean before it would only turn on for about two seconds without me touching any wires without me doing anything turn on for one to three seconds maybe and then it would shut back off so to verify we don't have any voltage other than the standby here so I'll just check between ground and say well let me check the standby to verify so I'll hear standby five volts let's check this yellow pin you're a tiny bit of voltage there point three volts there standby let's check this gray zero volts to check these pins over here these are red yeah not really anything and I think these are actually nothing because even when I so let's say I'm in here even when I pull this enable pin yeah it stays the same so those voltages aren't real so we may have had output for a few seconds there as you heard the fan on and just like before it drops out so again that signifies we do get power down to that bottom board and I'm just gonna check something quick so I know that see better keep the jumper in there between jump hurt again hmm I know that our input line is right here so there we go 120 volts that's a connector coming into this top board now I have can't see it I'm not gonna manipulate the board right now because there's power applied but there's a connector right here these two pins have a connector on the other side those two wires lead outside a power supply and I have that jumper so the reason to jumper it is to bring the voltage from here which is from our input over to here and bring it to these this pin right here so the pins here this pin and this pin this is the output connector that leads to the bottom board so this is what's supplying AC voltage to the bottom board so there should be 120 volts there and there we go so that is powered leading to the bottom board so we know we're getting power down there what we're gonna do next is disconnect this top board obviously with the power removed pull it aside and see what we can find on the bottom board so there's something going on in that bottom board down there that it's only temporarily enabling the outputs so that's what we're gonna do next one more thing I wanted to do before I dive into deep since this does seem like it's going into some sort of protection mode for overload and we don't have a load on it I wanted to make sure that the fan cooling fan isn't what's actually bringing it down so I disconnected the fan which is connected to the bottom port there and I'm going to turn it on and I want to monitor for an output voltage and if we have one I'm gonna see if it drops out at all if not it might just be the fan loading it down so I will probe ground pin and arbitrarily yeah I want a clothespin so it's easy for me to hold [Music] all right so this is ground and red and I apologize you won't be able to see me kind of hold it in place but you will be able to see the meter so I'm gonna plug it in and of course we will not hear the fans turn on because the fan is not on but we're gonna see if we get an output voltage and if so how long does it remain you hear the relay click and we do have an output voltage five point five volts we did not have there that there before so again I'm on the yellow pin excuse me I'm in a red pin I'm gonna try another pin and there's yellow and we have an 18 volt output interesting let's try you already know purple stand by here's another 5 volt from a grape in try this orange pin here and I can't see what I'm doing here so I'm just going along testing each pin with different color anyway and here's the orange orange is three point three and of course they're tied together so two oranges three point three will go to the other side and there's one or two different connectors here so red again is five and it's showing five point four another red I can get it in there great there you go five point four again let's go to white weights gonna be different six point six okay negative six point six don't you see that that's negative and blue blue is different negative 15 mm-hm so I'm gonna guess all these seem right except for that one should probably be positive 15 and what else we check I thought there was another abnormal one ground 5.4 around 3.3 yep so we still have an output that is much longer than it has lasted in the past all right so I decided to pull the fan out of supply plug it in just to see the rotation and see how things were operating with it outside and of course it seems to be working I've had it on for maybe five minutes now fans running very well I don't hear any change in the rotational velocity or anything like that I can't hear kind of hissing from the supply I'm not exactly sure what that sound is and I've also noticed when I check my outputs here I dropped at least one voltage so check the 3.3 first a real good way to do this three points are you still there that's fine I know my five volts is still there five volts here five volts okay 5.3 five point three it's ground this is the pin we lost oh no it decided to work just a moment ago this was uh at zero I guess it is still working this is the one that's interesting this is that yellow pin this is the one that was at about 16 volts of course now with the supply or the fan on its dropped to thirteen and a half volts so the fan is using the 16 volt supply this should be 12 volts though this should be a 12 volt output let's go around and check some other outputs are still at 5.3 5.3 their ground I'm still waiting for my negative where's my negative that I know that blue pen is something different blue pen yeah there's my negative 12 and that's actually behaving you know that's pretty close to nine negative twelve right now you at twelve point seven and three point three so the only one that seems to be misbehaving is that positive twelve which is about sixteen even with the fan pulling on it it's still dropping out they said what was that again it's still a thirteen a half so it's still too high so that may need a pot adjustment or it may have something wrong in that output so a regulator or some caps or both so I'm gonna go ahead and power it down we're still running this has probably been on for ten minutes outside of the tool which was interesting outside of that supply I should say I'm gonna power it down pull off this top board again and take a look at that bottom board really closely would probably pull that bottom board out the output board take a look at the circuitry especially surrounding the positive twelve output let's see if I can find anything abnormal there very likely some bulging capacitors electrolytic capacitors maybe some other issues down there try and take a look at the the regulator down there as well so I will take off this top board and I'll be back what I did since I'm not gonna be reusing the supply even when it's fixed what I did was I pulled out a bunch of the inputs so there were maybe six separate connectors on this and you can see right here these little holes those were all outputs to different connectors and there were a few more here that are kind of buried but I pulled all those out leaving just our main connector behind because this is the one that it's gonna have all of our voltages on it and I'm doing this purely for the joy of repairing it so I'm not I'm not repairing this so that it can be used again because we have a replacement supply we don't need to put this repaired supply in and it's it's a pretty cheap supply so I'm doing it just for the thrill of the repair this is my passion one of my passions so that's why I'm doing it so just to make a little bit easier to work on all I have is this one main connector it's a little bit easier it's a little less cluttered down here so that's what I did there but then all of our outputs are over here and they're labeled pretty well on the board I don't know if you can see that but they are you can see +5 volts this one's actually okay it is labeled + 12 volts so they kind of go in a row here horizontally so you have plus 12 coming in here plus 5 here ground and then plus 3.3 you can also see the minus 12 right there minus 12 on that blue right there and then minus 5 so here's our two negative voltages plus 12 plus 5 ground + 3.3 and they kind of go in a row and obviously took out the first rows to make a little bit easier to work on and as I said I don't need those extra connectors so you're the fan plugs in by the way you can see that where I'm pointing there we go so that is definitely plus 12 you can see it's right in line it's tied to the plus 12 I found it on the back here so here's our connector for the fan and this is our plus 12 line right here so it is 12 volts and again we're outputting 16 volts so something wrong with the regulation or filtering there so now what is wrong with this board well as I thought it may not be the only problem but a major problem are these caps so these filter caps down here you can see you got five big caps right here one two three four five four of them are severely bulged on the top so this one looks to be okay so much to be okay this one's very bulge this one's actually all three these are really terrible okay and that's part of the the output filtering so that could definitely cause a big issue with their outputs there unfortunately I don't have my ESR meter anymore I left it where my kids could get it and they got it and it's it's broken so that was my bad I'll have to get a new ESR meter but I would definitely test these in circuit and then I'm gonna pull them I'm gonna pull them anyway and I test them on a circuit I can almost guarantee that these would be bad this one might be bad as well but I'm definitely gonna replace these four caps and if I still have an issue I may pull this cap as well they look to be all identical I'll have to look at the ratings the specs and I'll replace them I'm not gonna put new caps in definitely not gonna put money into this as I said this is not you know I'm not gonna make any money off this and I'm not gonna reuse it so I'm just gonna pull some caps from a spare board that I have are several spare boards and I'll pull all these or replace them I'll put everything back together and power it up and we'll see what kind of output we have maybe our 12 volts is actually down 12 volts and you know everything will work out if not there are several adjustment pots on here there you go zone right here vr two one right here vr three this one kind of hidden behind the wires right now right here that is VR 1 so 1 2 or 3 there's got to be a fourth somewhere and maybe for some other output one two oh one two three I'm sorry so no there doesn't have to be a fourth so one of these may adjust the 12-volt so if these caps don't fix it which I think they will or they're gonna help I'll take a look at which potentiometer here which variable resistor is in line with that 12 volts and try and adjust it but for it to be out by 4 volts plus that's pretty bad 30% it's very bad so I don't know if a potentiometer adjustments gonna bring that in probably more likely due to these filter caps looking at the other capacitors on the board you got these little capacitors here they're kind of hidden from view all right here tube caps there 2 caps here those look to be fine at least not that bulge is one cap here on the input that's an important one that one looks fine of course our filter capacitors are very important difficult to tell very difficult to tell if these are bulged or not with their plastic tops on there and again I don't have my ESR meter so I can't really test these I do have a scope so I could put no I don't want to I don't want to deal with that either but these caps look to be okay there's a couple of caps on this board here that looked to be okay a couple of caps down here I also looked to be okay so it's really just this output filtering section where the capacitors are gonna need to be replaced so I'm gonna go ahead and pull these five right now I would test the yes ARBs as I said I can't so I'll replace them and we'll test it while we have it out you can look at this board as well a little bit there's only a few capacitors on here so here again we have the input go through the main transformer that's tough to see but there's a rectifier right here and we have some drive transistors here and here as well and then we have two larger caps that are thought to be in good shape physically anyway so I'm not gonna touch anything on this board it's all gonna be on our output board five caps that I discussed one two three four five I'll pull those replace them put it all back together test it and I'll be back all right so I replaced all five capacitors on that lower output board I have my jumper reinstalled and my output cable and I reinstalled the fan as well just to simulate let's simulate but just to put it under the normal power on procedure that it's used to so ready to plug it in and we should hear the fan turn on and hopefully it turns on and stays on and we'll check the outputs again we're hoping that that twelve volts is much closer to 12 volts now so we'll take a look no fan make sure my jumper is well seated I just seated well plugged in no fan see if we have any output I did here the relay click I'm gonna pour it off and pour it on again can hear that relay click turn back on the relay clicks so that's the relay allowing power to be distributed to the bottom board so we do have power at the bottom board question is do we have any outputs we definitely don't have any fan I did plug the fan and I'll have to double check but I'm I did plug the fan so we'll check round to orange which is 3.3 volts we have that that's good let's check to read which should be 5 volts I point you to good and we'll go to gray I don't remember what that supposed to be 5 again these outputs are so again if you look at the supply zoom in a little bit here should have plus 12 minus 5 minus 12 plus 5 plus 3 and then our standby voltage so all right so we'll keep going here let's see we just checked the gray that was a little over 5 ground pin what's next purple that standby I have to have that should be right around 5 volts 5.1 now yellow this is supposed to be 12 we were getting 16 plus and look at that 11.66 so replacing those capacitors one or several or all of them allowed us to get that 12 volts or very close 12 volts so that's the correct output now just check the pins on the other side here so we already know red is five volts so double-check that five volts yep there's a white one of these should be negative five there's negative five okay and we'll check blue which I believe is negative twelve and that looks good too negative eleven point one five now that could probably use a slight adjustment to the potentiometer to bring that up but again I'm not using this for anything so I'll take that and then three point three on the orange again okay so I know the fan runs on the twelve volts and what was that outputting eleven point six that fan should be running so I am getting output power it's possible but I haven't checked but it's possible that the fan only turns on due to high temperature so there may be a temperature sensor inside the unit and when it reaches a certain temperature the fan will kick on and it just may have been that it was kicking on before due to due to a malfunction or just because something was overheating due to those capacitors so I can try and simulate a hotter event you know an over temperature event to try and see if that fan kicks on but I think first I'll open the cover I'm gonna double check that I have my fan connected and then I'm just gonna check the output to the fan connector just to see if we're getting voltage but maybe it's just not enough voltage or perhaps we're just not getting any voltage because as I said it could be temperature related so I'll take the cover off and we'll take a look all right very simple fix for this one mm-hmm so what I did was the power applied took a look at the fan you'll see it's got this grating on here obviously to help you know exhaust the air through the power supply to cool it down but I stuck obviously carefully stucked his dental pick in I manually spun the fan to see if it had any resistance it it actually did have some resistance to it a quite a bit so that maybe there's some sort of holding current on there but that wasn't the case it start of sort of started slowly to spin up but you can hear it still felt like it had some resistance so when I took the cover off I discovered that one of the wires that I reinstalled reattach the outer casing of the wire was brushed up against part of the fan blade and so fan blade just wasn't able to start so I have it powered up I'll just put the jumper in and you'll hear the fan start so again I'll jumper it hear it start right up and say jumper it of course that goes it sounds really good I'm really smooth so I'm gonna double-check my outputs now that the fans running 12 again it's running on the 12 volt so we'll definitely want to check 12 volts okay 3.38 for the 3.3 volts that's pretty good see we have for the red that should be 5 volts 5.2 gray I believe is 5 again 5.2 Purple's are standby 5 volts yellow is 12 volts look at that 12 point zero 9 and the reason why it was lower before eleven point two eleven point three it was because it was the fan was dragging it down so that there was a lot of current being drawn through the fan as it was trying to trying to start now that the fans running it's it's a nice solid twelve point one zero so that's really good happy with that and there's a couple of old Stooges back here it's a negative 5 and a negative 12 that will check again so negative 5 is the white negative five point zero seven very nice and the negative 12 is a blue negative negative eleven point three six and again if this was a supply that I was fixing for somebody or if it was something that was gonna be put back into use I would attempt to get those voltages as near as spec as possible with the potentiometers on the board but again this is pretty darn close we got rid of the 12 volts reading 16 volts issue by replacing the capacitors fans also working very nicely now it's it sounds really nice and all the outputs are there and they're pretty darn accurate so I'm happy with this I think this is a solid repair so this one's all done again if you have something you want to send to me in most cases I will look at it and attempt to repair it for free so if you have some sort of power supply benchtop power supply or otherwise if you have say a home audio system or a flat-screen TV nothing to do with the screen no screen issues but some sort of power issue I'll put issue go ahead and send me a note in my channel on YouTube here at duality and I will get back to you with whether or not I'm interested in able to do something like that and again in most cases it's going to be free free to you so just let me know and the only cost to you would be shipping and potentially a you know component replacement which would probably be next to nothing if any know what's being replaced so thanks for watching stay tuned I'm going to be doing a video very soon on a bose system that I just bought on ebay for very cheap the complaint is it will not power on so my next video I'm going to take that apart we're going to figure out why it's not powering on and we're gonna fix it and it these are really nice systems I don't have one myself I may keep it for myself or I may sell it because I would get a good amount of profit from this so stay tuned let me know what you think of this video thank you you