Of all the switcher topologies, the buck is the gentlest on its filter capacitor. All other topographies are not so gentle. The buck has to accept a triangular current waveform with a DC component on top of it. The DC current is simply the load current. However, the triangular current goes directly to the filter capacitor, which ideally integrates the current as the capacitor then maintains a smooth DC voltage of the output. What kills this capacitor in the long run is the capacitor's Equivalent Series Resistance (ESR). The triangular current passes through the ESR. As everyone here knows, current passing through a resistor creates I^2*R power losses, which in turn creates heat. Capacitors do NOT like heat. Heat dries the capacitor, resulting in capacitor death. Vendors like China Inc.are seldom aware of these problems, so they use a cheap electrolytic capacitor, that has a very large ESR, as the switcher's output filter cap. Eventually, POOF! Clive did the proper thing here in reviving the switcher: he used a high quality Panasonic capacitor designed for switchers, meaning that capacitor has a low ESR. For the record, you can tell when a capacitor is rated for switching applications because its ESR is tested at 100 kHz, where a cheap low frequency capacitor is tested for 60 or 120 Hz.
Just for new electronic engineers... Electrolytic capacitors can have a rated life as low as 2000 hours at max operating temperature. That's just 83 days. Provided other parameters aren't exceeded, the life expectancy doubles for every 10C reduction in temperature. So using good makes of capacitors with a higher temperature rating and keeping them cool is essential or you will have a lot of warranty returns. The Panasonic capacitor Clive used is a pretty good make.
@@User-w7ckl Yes, the electrolyte either evaporates or leaks. As it dries out the Equivalent Series Resistance increases and this can cause increased heating and accelerates the problem. In extreme cases you get gasses building up inside which can bulge or burst the safety vent (X on the top of aluminium types).
@tec4303 If you must use electrolytic capacitors then select a good make and make sure they operate in a cool environment. 20 years = 175,000 hours. Some capacitors are rated for 5000 hours at 105C. So they should last 10,000 hours @ 95C; 20,000 hours @ 85C; 40,000 hours @ 75C; 80,000 hours @ 65C, 160,000 hours at 55C. So you need adequate cooling to achieve long life. Best advice is to consult the manufacturers. Things like the ripple current also have an effect.
Fun little repair for a New Year’s Day. I’ve been soldering since I was around 10 years old I am 65 now, but when I use an iron that close to my fingers while slightly struggling to remove something, it almost always guarantees a burn. And a few well chosen words to confirm the mistake.
I've just remembered.. There's a TH-cam channel.. 'Dave Knowles' .. on which there are Jack Hargreaves films .. he was on 'How' the TV programme answering questions. Something nice while the weather is.. wet!
Small note: electrolytic capacitors failing in modern gear (as in, not in old 80's stuff) do so because the OEM failed to install a LOW ESR capacitor in a role that involved fast switching. See, any electrolytic capacitor is fine with the job of smoothing a mains powered 50-60Hz ripple. As in, a mere few dozen times per second. But modern electronics use switching power supplies that empty and refill those electrolytic caps many dozens or hundreds of THOUSANDS of time per second - and at that rate, the ESR (equivalent series resistance) of the cap DOES matter, with all that current sloshing in and out boiling the capacitor's electrolyte through sheer resistive losses if it ISN'T a low ESR cap. So... companies cheap out, or just doesn't care, cap says "uh-oh, I'm toast", product dies. Everyone goes surprised Pikachu face except the engineers who go "oh, FFS..."
Unfortunately, you see this even in products produced by so-called reputable manufacturers. A reliable design would use a two-stage filter and surge suppress. I'm not sure whether this is manufacturers ensuring their products only last a few years or bowing to consumerism or just bad design (or a combination).
@@ralphj4012 Surprisingly Panasonic DVD recorders don't use Panasonic capacitors but some type that is notorious for failing after about eight years. Buy a faulty one and there is a big chance that some capacitors have blown their tops.
Thanks Big Clive. I like the "proper" fix it videos. I think what's cool about these is watching your techniques and commentary throughout. More gold there in tips and actual working knowledge.
Heating the pad or the pin and banging the pcb on the bench is my favorite way to get rid of excess solder ;) Nice and clean repair. Very profitable too, doesn't cost much in time or component, and save a thing that surely cost something.
Sorry Clive, got to give you an A- for the flick technique. To get an A+, you need to bang either the PCB or your wrist on the workbench. The rapid deceleration creates a whiplash effect which in turn, removes more solder.
I bought over 30 smart sockets already, starting few years ago. Recently one by one all started failing. At the beginning the vendor replaced few broken sockets then he stopped. Finally I opened one by one and replaced capacitor - imagine: till today I replaced already all of them - wtf? They put so low quality capacitor or what? The ones I put where a bit higher voltage (16V), the originals were 10V - maybe this was the reason? The only big problem is: once the socket is opened, it will NEVER be the same again :-( Anyway, you nailed it ;-)
As soon as the video started, I said “It’s the damned capacitor, Clive!”. I’ve repaired so many of these dinky little power supplies. See you tomorrow for the stream.
@@erikkovacs3097 25 years before I was even born I had a moment of clarity and blurted out "it's the capacitor!" without understanding the context or world-changing significance!
Hi Clive. Pro Tip - slip a short length (12mm) of 1/4" silicone tubing over slightly shortened (2mm or so) solder sucker teflon tip for perfect seal and perfect solder removal. Works perfectly on single sided boards and THP boards when rosin flux is present. After a few hundred joints you may need to cut the silicone tubing back a couple of mm to expose new good end. If the teflon tip gets clogged (rarely) a quick poke with hot solder tip sorts it out. I have not bought any of that expensive solder wick stuff in 25 years haha. Thank you for such educational and informative content and the wry humour. Cheers from Downunder.
@@ericmc6482 I used some rubber Hellerman sleeving I got off old wiring looms, and they worked well. Then used some PTFE sleeving I also got, which also works well.
This video inspired me to actually try fixing my half-broken Blitzwolf smart plug I had laying around. It started acting up while turned on, causing the relay to click off and on for a split second every few minutes. Thankfully it was easy to open as it was just screwed together and no glue/plastic had to be cut. Inside I found two 4.7uF 400V and one 220uF 10V capacitor. I remembered I had a capacitor kit I bought a while back, and it included a 220uF 10V capacitor. I got the old one out, and put the new one in. To my surprise, that was all it took to make it work normally again! To be honest I didn't expect the issue to be as obvious as a capacitor since it's only a few years old by now, but when you talked about failure by high frequency I though it was worth a shot to fix it. As the capacitor kit came from AliExpress with just generic no-name capacitors I expect the plug to fail again some time later, but at least now I know what to replace!
I've actually found leaving a little bit of the end with solder on it makes solder wick work a bit better because it will wet immediately. I've also generally found it's not always best to have the wick between your iron and the joint--in fact I often flow the joint with my iron and _then_ bring the wick (with flux on) to it and try to touch the iron to both at the same time. Iron to dry wick does not make very good thermal contact and you'll burn up all the flux on it which will blacken your iron tip and make the thermal contact even worse! To put it another way: having some solder on the iron and/or the wick can counter-intuitively help remove solder because it provides a more instant thermal contact. Additionally, sometimes it makes sense to have the iron on the joint instead of (or in addition to) the wick, depending on how much heat the joint needs.
Yep.. I agree. Solder wick braid takes a little practice to get proficient with it. Sticking the end of the braid into a tin of paste Flux helps with those stubborn situations also..
Freezing sockets like this is a good way of getting the glue to break free. Then they can be glued back together and be far less likely to come apart after (YMMV).
Nice little fix. Dead electrolytics, the true menace. Silicone glue on recombobulation, and it won't come apart before it is properly spudged. 6:32 ...and see if it was not a Fluke! :)
I have a trio of the old "Weller" brand soldering "guns" that I keep around for heavy soldering like those power pins. They each have dual heat settings and an old incan flashlight bulb to light up what you are working on. I believe the wattage on the guns is as follows.. 100/140, 200/260, 250/300. Pull the trigger half-way to the first click, and you get the lower range, pull it to the second click and you get the high range. The tips heat up very fast. I'm sure ANYONE who has been into electronics for any amount of time has had one of these Weller Guns at one point, and is familiar with them. For anyone who isn't aware, Weller still sells replacement parts for these 50 year old solder Guns, such as replacement cases, switches, and so on. I was surprised when I saw the parts on the website. Very good soldering devices to have around for large, heat sucking, solder joints.
One day, bigclive, one day earlier and you would have saved me screwing up my own fix of a similar "smart" switch. Same issue, same part value, though mine was more obvious: the 470 uF cap had blown its can completely: at first I thought it was mounted "high" to get away from the heat of the inductor, then I realized that that wasn't insulating tubing over the leads, it was the cardboard guts of the cap. So far so good. Where I screwed up was trying to pull the plastic part off the power leads, thinking it was a friction fit, rather than desoldering it like you did. Won't budge, so I broke out the heat gun. Yup, still wont budge, but now it's not even close to "flat". So now that you've shown me the way, I'll de-solder it and fix it. I guess I'll have to find an alternate packaging solution: perhaps wire a cord to it and put a big old "gland" over the spicy bits.
Here's another example of 'time-bomb' components- Just fixed a family's toy Christmas train, an expensive Disney themed setup. After a few Christmases' of use it couldn't run for long before crawling to a halt and 'motorboating.' (Strange describing a train engine as 'motorboating') 7.5V Battery (5 x C-cell powered) Examination revealed a very hot component in the power input stage of circuit board. It was a SMT Polyfuse. Intended, I assume, to reduce power if engine has stalled. Sadly polyfuses have a limited number of operations before triggering at lower and lower currents. This one was rated at 1.5A nom, 4A trip, 8v max The motor is PWM controlled, average currents seldom exceed 1 amp. Probably not a factor but PWM does produce high current peaks. Interestingly, the polyfuse partially recovered after it's ends were re-soldered. Not for long though. Replaced it with a slightly higher current rated through hole polyfuse (and a much higher max voltage rating). It happily passed a reasonable time-soak test. Happy Family.
Not sure what behavior you refer to as "motorboating", it seems to be beyond my knowledge of tech slang and as non-tech slang it refers to a particular form of lovemaking . Also your dozens are more like scores (5 to 9 scores in mains frequency CPUs) .
Regarding "flicking off" the old solder blob: I actually intentionally drop parts like these from 10cm and less. In my experience it works quite well to also clear solder from small and big holes .
I've also used a stainless steel paperclip to physically move the solder out of the hole while molten. Or a toothpick. Solder doesn't stick to these things. I always break something when I flick.
@@pault6533 I don't recall who recommended this to me/us, maybe BigClive, or maybe AvE: I have bought a set of needles (actually hollow needles, like syringe needles) of various sizes, stainless, that can be inserted into a solder hole, sometimes even additionally to/over/around the component lead. Insert while hot and retract when cold, this sometimes makes it easy to remove/unsolder a component, specially if you want to keep/reuse it later and need the leads.
Thank you so much for taking the time to look at this for me! there must be 1000s in the bin in UK! I will carry out your process for the other 8 i have and any further that go faulty, though the first batch still performing , once i get one running i will confirm the fix, those you have need a reset to default and app (smart life ) download , account and sync with your wifi , again Thank you for investigating and giving me the key to getting them working again , Happy new year !
I repaired a set of kitchen scales over Xmas for my mother. Dodgy tare button. Fairly simple soldering job to replace a 5mm tactile switch. That was until a pad tore off the PCB. The PCB designers hadn't connected all the legs of the footprint unfortunately but nothing a wire link couldnt fix. Good as new and second time I've swapped one of the buttons .
Thanks for this. I have a similar model that had a seized relay. Inspired by this video I opened it up (fairly easily) and was able to source and replace the relay. The relay was on a daughterboard so I was able to replace it without any heavy duty de-soldering. I also added an RC snubber across the contacts which will hopefully reduce the likelihood of this happening again. It sealed up quite nicely with a bit of superglue. Edit: One oddity, the relay daughterboard was double sided - BUT - the hole to the relay coil was not plated through and the connection was on the top. It had to be soldered on the top side, slightly proud, then I had to melt it from the bottom side and push it down. Very odd cost saving measure and bit of a head scratcher for a bit!
The little side button on such devices are usually there to allow you to turn the socket on if you are near it and don't have a phone handy to switch it in the app, AND also there to hold it and reset the device and clear out any account info.
To clean out really troublesome througholes I'll push a wooden toothpick through the hole while I melt the solder with my iron. 99.999% of the time it's always a capacitor that's gone pop... Excellent repair Clive. Merry Christmas and a very Happ New Year... 🎄🎄🎄☃☃☃🎅🏿🎅🏿🎅🏿
This is quite a timely video; I've got a very nice WiFi-enabled schuko-type relay that can also measure voltage, amperage, power factor and all that and I've been using it happily for over a year, but it's just recently started to randomly crash. I assumed one or more of the caps inside've gone bad, so I'll need to open it up one of these days and see about it. Probably going to be about as easy a fix as in your video.
Brilliant repair Clive and explanation but 16Amp through one of these devices and then just using the plug connected to it as a safety net hopefully with a 13A fuse now that is dangerous! You are absolutely correct to recommend 5A maximum
Hi Clive. Second Pro Tip - folding the end of solder wick back 5mm or so forms a nice pad that sucks up all remnant solder and protects pads from damage. Cheers.
Master-class work, as usual! I started buying some of these wifi-enabled outlets for as little as $2-3 USD on AliExpress, and now I know what to look for when I take them apart for inevitable repair 🙂.
I have one of these plugs, running on Tasmota. They're excellent, however one died and, after taking it apart, I noticed this very capacitor was all swollen and leaking. It is exactly as this video demonstrates. It's a weak spot and they're prone to failing. Otherwise though, especially when running Tasmota, these plugs are excellent and incredibly useful.
I've been using these remote switches for nearly 5 years now,it allows me to turn on smd lights at work if I get an alarm on my cctv,thank you for the video as always,i never overload them,have all my Christmas lights on them too so I can turn them on and off at whim on my phone,they were quite cheap too
470, 10v capacitor is the most common fault in smart plugs after a year or so especially with plugs remain ON all the time. One of the sign of this bad capacitor is the relay keep turung IN an OFF and smart plug unable to connect with WiFi.
I had to open a couple of my smart plugs to access the wifi module and its serial port (UART) to flash a custom firmware and those things are a pain to open, also I couldn't really desolder the PCB so I had to essentially pry it from the case just enough to solder some wires on the module contacts on the underside. As for closing them again I have to say a generous amount of hot glue around the border (applied before closing it) does a decent job at holding it together and also if you need to open it again for whatever reason you can let some isopropyl alcohol through the seam to unstick it
Yay, I just bought two of these a day ago (differently branded, & for Zigbee, but they look exactly the same). I'll only be using them to charge a tablet every so often, so with any luck they won't fail on me. Some epoxy around the edge once the cap is replaced should make them plenty solid though.
I had 2 of these , both failed within weeks of each other , typically I binned them both in the pre Xmas tidy up , and now I’m watching this !! Oh well , live and learn , there’s always next time !! Ps the current monitor and consumption is quite accurate, happy new year to you Clive
This is useful to know.... I bought a set of four from Wilko when they were selling up. I have yet to introduce the juice to them, but my intention is to use them for turning on the Christmas lights next year. They look identical to the one you have there ....
Deja vu. Done same think last week. I use one of these to control mine printer and its ethernet to wifi bridge. Its a bigger problem when wifi module goes with the capacitor, but that did not happened on this last one For the record, no surprise the relay cant control 2KW electric heater. I get fedup of explaining to people not to use timers and controller plugs on them. This one lasted mine laborer for one week. The plumbers solvent cement glued it perfectly. I consider solvent cement as natural part of Mine diy repairs.
The satisfaction of seeing a product fixed is awesome. I have a few books now that i got as a Christmas gift on how to check and repair simple electronics. I'm excited to learn and hopefully one day successfully fix something on my own. I really enjoy your videos sir. Thank you and look forward to 2024. Side Note- is it time to make a video on things that go pop?
I have a lot of those WiFi sockets, so now if one goes south, I'll have an idea of how to fix it. Thanks Clive and thanks to Gordon for sending it you to take it apart. I wonder if the LED WiFi bulbs have that same issue when they stop working.
*Summary* *Introduction* - 0:00 - Gordon sent two malfunctioning Zang Hwang LSP A7 Wi-Fi smart plugs for repair and analysis. - 0:22 - The plugs are 16 amp, small-sized, and feature-rich. *Circuit Board Examination* - 0:39 - Circuit board exposed, showing socket connections. - 1:00 - A dim blue LED indicates malfunction; the device draws about half a watt. - 1:50 - Circuit board details: A single diode, one capacitor (instead of two), a buck regulator, a 3.3-volt regulator for the Wi-Fi module, and a chip for current monitoring through the load. *Suspected Fault and Repair Process* - 3:07 - Suspected fault in a capacitor part of the buck regulator. - 3:25 - Desoldering the circuit board to access and replace the capacitor. - 5:11 - Observing slight bulging on the faulty capacitor. - 5:24 - Removal and replacement of the faulty capacitor with a slightly larger one. - 7:31 - Reassembling the device after capacitor replacement. *Testing and Conclusion* - 10:57 - After repair, the LED lights up, and the relay clicks, indicating functionality restored. - 11:46 - The failure was due to the high-frequency handling capacitor. - 12:22 - Suggests that such a repair is common due to capacitor issues in modern devices. - 12:33 - Warning about safety concerns post-repair due to potential weakened structural integrity. - 13:12 - Concludes that the issue was an easy fix, commonly seen in devices with switch-mode power supplies.
Clive, as a power station electrician (bench electrician hobbyist) I enjoy your content as it makes me feel better about my soldering frustrations 😂. You do an amazing job of turning PCBs into electrical diagams on your videos. If I was an educator I would use your content to demonstrate various points. Keep up the great work despite your woefully inefficient 50hz supply.😂
Great job thank you , but if i may suggest: Heating the side of the casing should be good to open it without damaging the edges , then adding some super glue will be safe to use
Hi thanks for a good fix. But I would use the solder mop with a little Flux to desolder the pins from the pcb at the start. Good super glue and bit of good quality tape around the plug at the end for extra safety 👍
I also tried to repair a similar item. Except, mine had that special aroma... Opened it up, lifted out the prints, was greeted by a huge black skidmark on the inside and some more of that aroma. The supply board itself had a hole that looked like the caldera of an inactive volcano. I couldn't make out what caused the problem. Probably one of those components that were now degraded into black crumbles, loose in the bottom of the enclosure. I tried giving it 5V from a bench PSU but there was no life anymore.
assuming you havent got a vacuum operated de-soldering station, the best method I've found for removing solder from through holes is to hold the board in one hand, heat the pad and literally BANG it down on the bench....yes, it really works :)
I've had half a dozen of these (made by 'Teckin') for some time now, and I periodically have to replace the damn caps. A satisfyingly easy fix, but a pain. Naturally, I'm far too cheap to buy another one for a tenner! Made me laugh as soon as I saw the thumbnail, and thought 'oh god, not another one...'!
Always interesting - as usual. The most common cause of faults seems to be faulty capacitors and the first thing to look for is bulging cases of electrolitics. It is good you always mention it. As regards "flicking off", it does work well but be careful in what direction you flick. In my much younger days (I am now 61), I once "flicked" and the glob of solder neatly flew in my ear (thankfully not in the depths of my ear canal). I learnt that lesson through a very painful experience. 😁
It's not the PCB ban for the small caps. The old ones had a very simple electrolyte based on glycol and boric acid. Because the new power supplies operate at extremely high frequency, the modern capacitors are smaller and use a more complex electrolyte.
As always Clive, excellent video , one observation about the actual design, if this is plugged in a wall socket, the inductor is below the capacitor, hot air rises, so more likely to heat up the capacitor, if they'd done it the other way around, it may have lasted longer, although being a sealed unit, it may have made little difference, it could be designed or planned in obsolescence , thus requiring a constant stream of buying replacements.
I bought 16 of these from Amazon about 2 years ago, branded as "Teckin". They work really well until they start turning on and off randomly and then refuse to come on at all. I tried to get one apart but realised that the case would be unsafe even if I repaired them. Only 10 of the original 16 still work.
Perhaps a "solder sucker" might be a useful purchase for desoldering? There are fancy ones with an iron built into them, so you don't need three hands.
Big Clive has more experience than most of us combined and the skill to hold 2 things with one hand . He probably doesn't need expensive motorized tools like the one you suggest .
Those are mainly useful for (almost) desoldering ICs, and even then you have to go in with the braid to clean up. Just switching a single two legged component, it is rarely worth it unless the desoldering station is permanently set up.
Watching at around 6:38…that is not how you make a Flux Capacitor Clive! Sorry, I’ll see myself out for that one I have lost count the number of capacitors I have changed to get things working again. I usually end up changing most of them once one has failed as they are either a) cheap, b) bad batch or c) both Good video as always 👍
@13'10" comment about 'That pesky capacitor' made me smile.... ...Bet the manufacturer smiles too, probably has a category for components that guarantee predictable medium term failure... maybe 'terminators'?
I find using ceramic tweezers with cut off sections of solder braid makes it easier to retain the heat in the braid (not using the rest of the roll as a heat sink), but for simple jobs i just do like you did.
Q: Is connecting an electrolytic capacitor backwards the only way to get it go bang in a most exciting manner...? A: Oh, no. Dropping one of them into the molten solder bath of the selective soldering machine you're operating will do it quite nicely...
Couple million solder joints on record .. masterfully single-handedly doing the most difficult connections .. still wondering if it might go horribly wrong .. 😆
Yup, I bought a few brands of wifi smart lights. Two from the one brand I was testing failed. They all advertise 25000 hours with LEDs but that’s depends on the quality of the other components. For the VoColink brand they both failed with swollen capacitors.
To glue the plug together, I would dump a decent amount of baking soda in the cup, add a generous amount of CA glue to the perimeter of the backplate. Press the pieces together with the cup on the bottom, then invert it and shake gently. That would create a pretty solid bond.
When I opened one of these to re-flash the MCU to ESPHome, I found it didnt close up properly like you. I just wound some electrical tape around it between the pins and avoiding the holes, which seems to have held. If it doesnt, there is always the RCD under the stairs :)
Most of my smart IOT devices are liberated from the chinese by reflashing the onboard esp or tuya chips with Tasmota or openbeken, they are now local Lan & mqtt controlled instead of the "Internet required Cloud" and are better to use. Multi relay devices are all on or all off by default configuration but once liberated you can control individual relays and have greater control over what is connected. I say goodnight to Alexa and it turns lights on and off as I go to bed (yup lazy as can be)
dude, can you make a tutorial (series) for that sort of thing? Being able to actually use hardware that's been discontinued by the manufacturer and the requirement of their proprietary cloud service has rendered them useless, would be incredibly useful for consumer freedom and reducing waste. ... maybe big clive or perhaps Louis Rossmann can do that, if they realize it's an option - Louis would definitely love it.
@@TheDZHEXflashing a no-cloud firmware like tasmota on any of these esp is quite easy once you figure out the pinning of the chip yourself or if you find it in the numerous documentation pages made by the community
While most esp8266/esp32 devices, and older Tuya devices are easily flashable with Tasmota or ESPHome (which I prefer for Home Assistant use since you don't need a separate mqtt broker) and many even have programming headers, newer Tuya devices like the LSPA7 use a proprietary microcontroller module that can't be flashed yet, even if you can get at the module. It's a shame really because these are cheap (I have a few) and unobtrusive, compared to something like a sonoff.
I had four unbranded smart plugs from Amazon that looked exactly like the ones you work on here. They all failed at the same time so I assumed a software problem. Found several articles on how to reset them but nothing worked. In the end I gave up & sold them on eBay as 'not working -- spares or repair'. I wonder if the buyer got them working.
For the to-link Kasa smart plugs it’s usually the relay that welds closed. Mine started to do this after a year. The temporary fix was to whack the smart plug on the work top and the contacts became free until next time. I did think of sending it to you but I couldn’t identify the miniature relay 🙄
My pro-tip?, buy Sonoff switches, I've been running 2 x Sonoff S26 (eu type) switch sockets. Flashed with TASMOTA as soon as I got them, they've been working fine ever since, both are at least 3 years old and show no signs of failure, notably they all only have light loads plugged in, no kettle or heaters. I also have 8 other Sonoff based switches for ceiling/cupboard and closet lights, all are very, very reliable.
To be honest you can buy them for next to nothing now. I believe they are between £5-10. I kind of want to put one outside and shove an electric heater on one to see what would happen :)
I've done numerous repairs of low end gear involving similar caps glued to (or very close to) overworked heatsinks or coils... Pretty much guarantees the item survives the enthusiastic ''new-toy' period and fails when the user might be in the mood for another new toy.
@4:41 - I once saw a chap take a paper clip that touched multiple pins of low-melt and he was able to heat the paperclip and heat multiple pins at one time.
Thankfully UK sockets are generally switched so if the cover of such devices comes away then we can isolate it. Sideways glance to Technology Connections 👀
I use a lot of those WiFi sockets. (Yes I do a lot of home automation , because I a lazy git ) I wouldn't use a load above 10amps with them, mine are used for light loads such as table lamps ect. . Theses WiFi sockets are usually very reliable, I only had one failure in 10 years I've got 15 in use around my house , to be honest there cheap so repair is not worth while, but a very interesting video nevertheless
Gordon here, update, I can confirm i changed the caps in 9 of my duff plugs and they all worked as they should, thanks Clive
Of all the switcher topologies, the buck is the gentlest on its filter capacitor. All other topographies are not so gentle. The buck has to accept a triangular current waveform with a DC component on top of it. The DC current is simply the load current. However, the triangular current goes directly to the filter capacitor, which ideally integrates the current as the capacitor then maintains a smooth DC voltage of the output. What kills this capacitor in the long run is the capacitor's Equivalent Series Resistance (ESR). The triangular current passes through the ESR. As everyone here knows, current passing through a resistor creates I^2*R power losses, which in turn creates heat. Capacitors do NOT like heat. Heat dries the capacitor, resulting in capacitor death. Vendors like China Inc.are seldom aware of these problems, so they use a cheap electrolytic capacitor, that has a very large ESR, as the switcher's output filter cap. Eventually, POOF! Clive did the proper thing here in reviving the switcher: he used a high quality Panasonic capacitor designed for switchers, meaning that capacitor has a low ESR. For the record, you can tell when a capacitor is rated for switching applications because its ESR is tested at 100 kHz, where a cheap low frequency capacitor is tested for 60 or 120 Hz.
Just for new electronic engineers... Electrolytic capacitors can have a rated life as low as 2000 hours at max operating temperature. That's just 83 days. Provided other parameters aren't exceeded, the life expectancy doubles for every 10C reduction in temperature. So using good makes of capacitors with a higher temperature rating and keeping them cool is essential or you will have a lot of warranty returns. The Panasonic capacitor Clive used is a pretty good make.
Why is that? Does the electrolyte inside dry?
@@User-w7ckl Yes, the electrolyte either evaporates or leaks. As it dries out the Equivalent Series Resistance increases and this can cause increased heating and accelerates the problem. In extreme cases you get gasses building up inside which can bulge or burst the safety vent (X on the top of aluminium types).
Excellent info and advice, thank you!
How can I design my circuits to avoid this? What can I do if I need a 20 year lifespan?
@tec4303 If you must use electrolytic capacitors then select a good make and make sure they operate in a cool environment. 20 years = 175,000 hours. Some capacitors are rated for 5000 hours at 105C. So they should last 10,000 hours @ 95C; 20,000 hours @ 85C; 40,000 hours @ 75C; 80,000 hours @ 65C, 160,000 hours at 55C. So you need adequate cooling to achieve long life. Best advice is to consult the manufacturers. Things like the ripple current also have an effect.
Fun little repair for a New Year’s Day. I’ve been soldering since I was around 10 years old I am 65 now, but when I use an iron that close to my fingers while slightly struggling to remove something, it almost always guarantees a burn. And a few well chosen words to confirm the mistake.
You could coat the part of the iron or your fingers with high temperature silicon.. reduces the ouchy heat 😻
Do you remember the Everyday Electronics magazine and the Ladybird book 'Making a Transistor Radio' ... and Camberwell Green.
Happy Time's 😻
@@mySeaPrince_ 😹👍🏻
@@mySeaPrince_Fond memories......sigh
I've just remembered..
There's a TH-cam channel.. 'Dave Knowles' .. on which there are Jack Hargreaves films .. he was on 'How' the TV programme answering questions.
Something nice while the weather is.. wet!
Small note: electrolytic capacitors failing in modern gear (as in, not in old 80's stuff) do so because the OEM failed to install a LOW ESR capacitor in a role that involved fast switching. See, any electrolytic capacitor is fine with the job of smoothing a mains powered 50-60Hz ripple. As in, a mere few dozen times per second. But modern electronics use switching power supplies that empty and refill those electrolytic caps many dozens or hundreds of THOUSANDS of time per second - and at that rate, the ESR (equivalent series resistance) of the cap DOES matter, with all that current sloshing in and out boiling the capacitor's electrolyte through sheer resistive losses if it ISN'T a low ESR cap. So... companies cheap out, or just doesn't care, cap says "uh-oh, I'm toast", product dies. Everyone goes surprised Pikachu face except the engineers who go "oh, FFS..."
Surprised Pikachu face 😂🤣
It's a simple matter of cost saving on the part of the OEM. Especially when the branding is "Randomly generated name from Shenzhen".
Unfortunately, you see this even in products produced by so-called reputable manufacturers. A reliable design would use a two-stage filter and surge suppress. I'm not sure whether this is manufacturers ensuring their products only last a few years or bowing to consumerism or just bad design (or a combination).
@@ralphj4012 Surprisingly Panasonic DVD recorders don't use Panasonic capacitors but some type that is notorious for failing after about eight years. Buy a faulty one and there is a big chance that some capacitors have blown their tops.
Thanks Big Clive. I like the "proper" fix it videos. I think what's cool about these is watching your techniques and commentary throughout.
More gold there in tips and actual working knowledge.
Heating the pad or the pin and banging the pcb on the bench is my favorite way to get rid of excess solder ;)
Nice and clean repair. Very profitable too, doesn't cost much in time or component, and save a thing that surely cost something.
Thanks for creating lengthier videos, Clive. Appreciate this kind of videos quite much. TikTokstyle shorts are fluff
Sorry Clive, got to give you an A- for the flick technique. To get an A+, you need to bang either the PCB or your wrist on the workbench. The rapid deceleration creates a whiplash effect which in turn, removes more solder.
I bought over 30 smart sockets already, starting few years ago. Recently one by one all started failing. At the beginning the vendor replaced few broken sockets then he stopped. Finally I opened one by one and replaced capacitor - imagine: till today I replaced already all of them - wtf? They put so low quality capacitor or what? The ones I put where a bit higher voltage (16V), the originals were 10V - maybe this was the reason? The only big problem is: once the socket is opened, it will NEVER be the same again :-(
Anyway, you nailed it ;-)
As soon as the video started, I said “It’s the damned capacitor, Clive!”. I’ve repaired so many of these dinky little power supplies. See you tomorrow for the stream.
Reading that comment first the whole time I was thinking he was about to get a shock 🤣
Before the video was even posted I knew it was a capacitor
30 years ago, as a child, I woke from a fever dream and screamed "It's the capacitor!".
@@erikkovacs3097 25 years before I was even born I had a moment of clarity and blurted out "it's the capacitor!" without understanding the context or world-changing significance!
I work in a hospital and whenever one of the med students has a problem with the diagnosis i say: "it's the capacitor"
Hi Clive. Pro Tip - slip a short length (12mm) of 1/4" silicone tubing over slightly shortened (2mm or so) solder sucker teflon tip for perfect seal and perfect solder removal. Works perfectly on single sided boards and THP boards when rosin flux is present. After a few hundred joints you may need to cut the silicone tubing back a couple of mm to expose new good end. If the teflon tip gets clogged (rarely) a quick poke with hot solder tip sorts it out. I have not bought any of that expensive solder wick stuff in 25 years haha. Thank you for such educational and informative content and the wry humour. Cheers from Downunder.
My Engineer-brand solder sucker has a silicone sleeve.
I thought of it first, 30 years ago lol.
@@ericmc6482 I used some rubber Hellerman sleeving I got off old wiring looms, and they worked well. Then used some PTFE sleeving I also got, which also works well.
Could we get an example of how to do this? I'm sick of using solder wick 😂
@@TeddieBean Just slip a length of silicone tubing over the teflon tip....search "Engineer-brand solder sucker" for an example.
This video inspired me to actually try fixing my half-broken Blitzwolf smart plug I had laying around. It started acting up while turned on, causing the relay to click off and on for a split second every few minutes.
Thankfully it was easy to open as it was just screwed together and no glue/plastic had to be cut. Inside I found two 4.7uF 400V and one 220uF 10V capacitor. I remembered I had a capacitor kit I bought a while back, and it included a 220uF 10V capacitor. I got the old one out, and put the new one in. To my surprise, that was all it took to make it work normally again!
To be honest I didn't expect the issue to be as obvious as a capacitor since it's only a few years old by now, but when you talked about failure by high frequency I though it was worth a shot to fix it. As the capacitor kit came from AliExpress with just generic no-name capacitors I expect the plug to fail again some time later, but at least now I know what to replace!
I've actually found leaving a little bit of the end with solder on it makes solder wick work a bit better because it will wet immediately.
I've also generally found it's not always best to have the wick between your iron and the joint--in fact I often flow the joint with my iron and _then_ bring the wick (with flux on) to it and try to touch the iron to both at the same time. Iron to dry wick does not make very good thermal contact and you'll burn up all the flux on it which will blacken your iron tip and make the thermal contact even worse!
To put it another way: having some solder on the iron and/or the wick can counter-intuitively help remove solder because it provides a more instant thermal contact. Additionally, sometimes it makes sense to have the iron on the joint instead of (or in addition to) the wick, depending on how much heat the joint needs.
Yep.. I agree.
Solder wick braid takes a little practice to get proficient with it.
Sticking the end of the braid into a tin of paste Flux helps with those stubborn situations also..
my best tip with braid/wick is to add more flux, the pen type dispensers work really well here. more flux more better.
Also use a braid that is the correct size...The one he used was very coarse for these small pads
@@denisohbrien 100% agree. The flux that comes on the wick is never enough, even on the nicest wick available.
Freezing sockets like this is a good way of getting the glue to break free. Then they can be glued back together and be far less likely to come apart after (YMMV).
I'll have to try that next time I need to open a glued device. Sounds better than cutting and snapping stuff.
Nice little fix. Dead electrolytics, the true menace.
Silicone glue on recombobulation, and it won't come apart before it is properly spudged.
6:32 ...and see if it was not a Fluke! :)
I have a trio of the old "Weller" brand soldering "guns" that I keep around for heavy soldering like those power pins. They each have dual heat settings and an old incan flashlight bulb to light up what you are working on. I believe the wattage on the guns is as follows.. 100/140, 200/260, 250/300.
Pull the trigger half-way to the first click, and you get the lower range, pull it to the second click and you get the high range. The tips heat up very fast.
I'm sure ANYONE who has been into electronics for any amount of time has had one of these Weller Guns at one point, and is familiar with them.
For anyone who isn't aware, Weller still sells replacement parts for these 50 year old solder Guns, such as replacement cases, switches, and so on. I was surprised when I saw the parts on the website.
Very good soldering devices to have around for large, heat sucking, solder joints.
One day, bigclive, one day earlier and you would have saved me screwing up my own fix of a similar "smart" switch. Same issue, same part value, though mine was more obvious: the 470 uF cap had blown its can completely: at first I thought it was mounted "high" to get away from the heat of the inductor, then I realized that that wasn't insulating tubing over the leads, it was the cardboard guts of the cap. So far so good. Where I screwed up was trying to pull the plastic part off the power leads, thinking it was a friction fit, rather than desoldering it like you did. Won't budge, so I broke out the heat gun. Yup, still wont budge, but now it's not even close to "flat". So now that you've shown me the way, I'll de-solder it and fix it. I guess I'll have to find an alternate packaging solution: perhaps wire a cord to it and put a big old "gland" over the spicy bits.
Here's another example of 'time-bomb' components-
Just fixed a family's toy Christmas train, an expensive Disney themed setup.
After a few Christmases' of use it couldn't run for long before crawling to a halt and 'motorboating.' (Strange describing a train engine as 'motorboating')
7.5V Battery (5 x C-cell powered)
Examination revealed a very hot component in the power input stage of circuit board.
It was a SMT Polyfuse. Intended, I assume, to reduce power if engine has stalled.
Sadly polyfuses have a limited number of operations before triggering at lower and lower currents. This one was rated at 1.5A nom, 4A trip, 8v max
The motor is PWM controlled, average currents seldom exceed 1 amp. Probably not a factor but PWM does produce high current peaks.
Interestingly, the polyfuse partially recovered after it's ends were re-soldered. Not for long though.
Replaced it with a slightly higher current rated through hole polyfuse (and a much higher max voltage rating). It happily passed a reasonable time-soak test.
Happy Family.
Not sure what behavior you refer to as "motorboating", it seems to be beyond my knowledge of tech slang and as non-tech slang it refers to a particular form of lovemaking .
Also your dozens are more like scores (5 to 9 scores in mains frequency CPUs) .
Thanks Big Clive. A 3D printed band (vase mode) glued to edge of base and to cover increases glued surface area for safety
Regarding "flicking off" the old solder blob: I actually intentionally drop parts like these from 10cm and less. In my experience it works quite well to also clear solder from small and big holes .
I use the "heat and bash" method. Just bash the thing against the table to dislodge the molten solder onto the bench.
I've also used a stainless steel paperclip to physically move the solder out of the hole while molten. Or a toothpick. Solder doesn't stick to these things. I always break something when I flick.
Percussive repair has been used since the beginning of time and repairs themselves.
@@Loscha Yeah, I'm a basher, too.
@@pault6533 I don't recall who recommended this to me/us, maybe BigClive, or maybe AvE: I have bought a set of needles (actually hollow needles, like syringe needles) of various sizes, stainless, that can be inserted into a solder hole, sometimes even additionally to/over/around the component lead. Insert while hot and retract when cold, this sometimes makes it easy to remove/unsolder a component, specially if you want to keep/reuse it later and need the leads.
Thank you so much for taking the time to look at this for me! there must be 1000s in the bin in UK! I will carry out your process for the other 8 i have and any further that go faulty, though the first batch still performing , once i get one running i will confirm the fix, those you have need a reset to default and app (smart life ) download , account and sync with your wifi , again Thank you for investigating and giving me the key to getting them working again , Happy new year !
Perhaps you can repair the with the solid type capacitors Clive mentioned.
This was a really great demonstration of practical "get 'er done" soldering techniques.
Pessimism is a good trait in this world. Keep it up. Good repair. I've done a few of these and it's usually the biggest cap failing.
I repaired a set of kitchen scales over Xmas for my mother. Dodgy tare button. Fairly simple soldering job to replace a 5mm tactile switch. That was until a pad tore off the PCB. The PCB designers hadn't connected all the legs of the footprint unfortunately but nothing a wire link couldnt fix. Good as new and second time I've swapped one of the buttons .
Thanks for this. I have a similar model that had a seized relay. Inspired by this video I opened it up (fairly easily) and was able to source and replace the relay. The relay was on a daughterboard so I was able to replace it without any heavy duty de-soldering. I also added an RC snubber across the contacts which will hopefully reduce the likelihood of this happening again.
It sealed up quite nicely with a bit of superglue.
Edit: One oddity, the relay daughterboard was double sided - BUT - the hole to the relay coil was not plated through and the connection was on the top. It had to be soldered on the top side, slightly proud, then I had to melt it from the bottom side and push it down. Very odd cost saving measure and bit of a head scratcher for a bit!
Thanks, I changed the caps and it worked as intended, I used to replace these socket almost every years, and now save me lots of money.
You can almost hear how happy this little thing is to be once again able to talk to its Chinese command & control server!
Great Job wirh again great Explanation, i'd love to see more of these live-repair videos from you.
The little side button on such devices are usually there to allow you to turn the socket on if you are near it and don't have a phone handy to switch it in the app, AND also there to hold it and reset the device and clear out any account info.
To clean out really troublesome througholes I'll push a wooden toothpick through the hole while I melt the solder with my iron.
99.999% of the time it's always a capacitor that's gone pop... Excellent repair Clive.
Merry Christmas and a very Happ New Year... 🎄🎄🎄☃☃☃🎅🏿🎅🏿🎅🏿
This is quite a timely video; I've got a very nice WiFi-enabled schuko-type relay that can also measure voltage, amperage, power factor and all that and I've been using it happily for over a year, but it's just recently started to randomly crash. I assumed one or more of the caps inside've gone bad, so I'll need to open it up one of these days and see about it. Probably going to be about as easy a fix as in your video.
Brilliant repair Clive and explanation but 16Amp through one of these devices and then just using the plug connected to it as a safety net hopefully with a 13A fuse now that is dangerous! You are absolutely correct to recommend 5A maximum
Hi Clive. Second Pro Tip - folding the end of solder wick back 5mm or so forms a nice pad that sucks up all remnant solder and protects pads from damage. Cheers.
Master-class work, as usual! I started buying some of these wifi-enabled outlets for as little as $2-3 USD on AliExpress, and now I know what to look for when I take them apart for inevitable repair 🙂.
I am impressed with your finger dexterity when you solder. If it was me, I'd burn my fingers on the iron and drop the whole thing on the floor.
What a great little repair job on an otherwise very useful device, nicely done!
Nice tricks of the trade with the flux on the braid, and the solder flick.
I have one of these plugs, running on Tasmota.
They're excellent, however one died and, after taking it apart, I noticed this very capacitor was all swollen and leaking. It is exactly as this video demonstrates. It's a weak spot and they're prone to failing.
Otherwise though, especially when running Tasmota, these plugs are excellent and incredibly useful.
I've been using these remote switches for nearly 5 years now,it allows me to turn on smd lights at work if I get an alarm on my cctv,thank you for the video as always,i never overload them,have all my Christmas lights on them too so I can turn them on and off at whim on my phone,they were quite cheap too
470, 10v capacitor is the most common fault in smart plugs after a year or so especially with plugs remain ON all the time. One of the sign of this bad capacitor is the relay keep turung IN an OFF and smart plug unable to connect with WiFi.
I had to open a couple of my smart plugs to access the wifi module and its serial port (UART) to flash a custom firmware and those things are a pain to open, also I couldn't really desolder the PCB so I had to essentially pry it from the case just enough to solder some wires on the module contacts on the underside.
As for closing them again I have to say a generous amount of hot glue around the border (applied before closing it) does a decent job at holding it together and also if you need to open it again for whatever reason you can let some isopropyl alcohol through the seam to unstick it
Thanks Clive, Happy new year and loved the play by play commentary! Looking forward to the next!
I'd like to see what that cap shows as on a meter, both capacitance and ESR.
Also, what rating did the relay claim?
I stuck the failed cap into a component tester and it showed up as a diode with a capacitance of zero for some reason.
@@bigclivedotcom Dried up then.
For a moment my brain tricked me smelling the solder. 😀
All the best for 2024, Clive!
Solder wick works a lot better if you cut off a small section. Stops the rest of the roll pulling all the heat from the iron. Thanks for the videos!
11:40 The button on the side is used for manual switching, if you do a long press, you'll reset it for Wifi connection.
Thanks for the informative video! it helped me to fix my smart plug after replacing the defective 470uF capacitor 🙌
On the plus, liquid metal sploshes are always so satisfying.
Yay, I just bought two of these a day ago (differently branded, & for Zigbee, but they look exactly the same). I'll only be using them to charge a tablet every so often, so with any luck they won't fail on me.
Some epoxy around the edge once the cap is replaced should make them plenty solid though.
Flashback! Drunk Clive trying to read the voltage off the picture. Lol. It was classic. I dunno why I just remembered it.
It's happened since too. It would be so much easier than probing the real PCB.
I had 2 of these , both failed within weeks of each other , typically I binned them both in the pre Xmas tidy up , and now I’m watching this !! Oh well , live and learn , there’s always next time !! Ps the current monitor and consumption is quite accurate, happy new year to you Clive
This is useful to know.... I bought a set of four from Wilko when they were selling up. I have yet to introduce the juice to them, but my intention is to use them for turning on the Christmas lights next year.
They look identical to the one you have there ....
Enjoyed your soldering tricks. Very useful to me as a beginner.
nice to see a repair video rather than a strip down one way video 🙂
Almost everything I strip apart gets reassembled afterwards.
Deja vu.
Done same think last week. I use one of these to control mine printer and its ethernet to wifi bridge. Its a bigger problem when wifi module goes with the capacitor, but that did not happened on this last one
For the record, no surprise the relay cant control 2KW electric heater. I get fedup of explaining to people not to use timers and controller plugs on them. This one lasted mine laborer for one week.
The plumbers solvent cement glued it perfectly. I consider solvent cement as natural part of Mine diy repairs.
The satisfaction of seeing a product fixed is awesome. I have a few books now that i got as a Christmas gift on how to check and repair simple electronics. I'm excited to learn and hopefully one day successfully fix something on my own. I really enjoy your videos sir. Thank you and look forward to 2024.
Side Note- is it time to make a video on things that go pop?
I have a lot of those WiFi sockets, so now if one goes south, I'll have an idea of how to fix it. Thanks Clive and thanks to Gordon for sending it you to take it apart. I wonder if the LED WiFi bulbs have that same issue when they stop working.
Happy New Year! 🥂🍾
Thank you for avoiding electronic waste once again. 😃👍
Wrong capacitor for the job, glad to see it’s fixable!❤
*Summary*
*Introduction*
- 0:00 - Gordon sent two malfunctioning Zang Hwang LSP A7 Wi-Fi smart plugs for repair and analysis.
- 0:22 - The plugs are 16 amp, small-sized, and feature-rich.
*Circuit Board Examination*
- 0:39 - Circuit board exposed, showing socket connections.
- 1:00 - A dim blue LED indicates malfunction; the device draws about half a watt.
- 1:50 - Circuit board details: A single diode, one capacitor (instead of two), a buck regulator, a 3.3-volt regulator for the Wi-Fi module, and a chip for current monitoring through the load.
*Suspected Fault and Repair Process*
- 3:07 - Suspected fault in a capacitor part of the buck regulator.
- 3:25 - Desoldering the circuit board to access and replace the capacitor.
- 5:11 - Observing slight bulging on the faulty capacitor.
- 5:24 - Removal and replacement of the faulty capacitor with a slightly larger one.
- 7:31 - Reassembling the device after capacitor replacement.
*Testing and Conclusion*
- 10:57 - After repair, the LED lights up, and the relay clicks, indicating functionality restored.
- 11:46 - The failure was due to the high-frequency handling capacitor.
- 12:22 - Suggests that such a repair is common due to capacitor issues in modern devices.
- 12:33 - Warning about safety concerns post-repair due to potential weakened structural integrity.
- 13:12 - Concludes that the issue was an easy fix, commonly seen in devices with switch-mode power supplies.
The little pushbutton over the LED that makes the relay click is to turn the socket on and off manually at the plug without a wifi connetion.
Clive, as a power station electrician (bench electrician hobbyist) I enjoy your content as it makes me feel better about my soldering frustrations 😂. You do an amazing job of turning PCBs into electrical diagams on your videos. If I was an educator I would use your content to demonstrate various points. Keep up the great work despite your woefully inefficient 50hz supply.😂
Great job thank you , but if i may suggest: Heating the side of the casing should be good to open it without damaging the edges , then adding some super glue will be safe to use
Hi thanks for a good fix. But I would use the solder mop with a little Flux to desolder the pins from the pcb at the start. Good super glue and bit of good quality tape around the plug at the end for extra safety 👍
Oh, nice, I got something similar and the cap is close to the edge so no need to desolder the board. I hope that does it. Thanks, Big C.
Excellent Clive, I've got one of those in that exact state.
I also tried to repair a similar item. Except, mine had that special aroma...
Opened it up, lifted out the prints, was greeted by a huge black skidmark on the inside and some more of that aroma. The supply board itself had a hole that looked like the caldera of an inactive volcano. I couldn't make out what caused the problem. Probably one of those components that were now degraded into black crumbles, loose in the bottom of the enclosure.
I tried giving it 5V from a bench PSU but there was no life anymore.
assuming you havent got a vacuum operated de-soldering station, the best method I've found for removing solder from through holes is to hold the board in one hand, heat the pad and literally BANG it down on the bench....yes, it really works :)
I've had half a dozen of these (made by 'Teckin') for some time now, and I periodically have to replace the damn caps. A satisfyingly easy fix, but a pain. Naturally, I'm far too cheap to buy another one for a tenner!
Made me laugh as soon as I saw the thumbnail, and thought 'oh god, not another one...'!
I have exactly the same ones and I'm so glad I can now easily fix the (four?) ones that have failed already in the same way!
About to embark on the same mission, would a better type cap negate to need to change em so often?
Always interesting - as usual. The most common cause of faults seems to be faulty capacitors and the first thing to look for is bulging cases of electrolitics. It is good you always mention it. As regards "flicking off", it does work well but be careful in what direction you flick. In my much younger days (I am now 61), I once "flicked" and the glob of solder neatly flew in my ear (thankfully not in the depths of my ear canal). I learnt that lesson through a very painful experience. 😁
Capacitors haven't been the same since the PCB ban. The various replacement electrolytes are all inferior to the real thing.
My first ever solder flick from the tip of an iron landed on my hand.
It's not the PCB ban for the small caps. The old ones had a very simple electrolyte based on glycol and boric acid. Because the new power supplies operate at extremely high frequency, the modern capacitors are smaller and use a more complex electrolyte.
As always Clive, excellent video , one observation about the actual design, if this is plugged in a wall socket, the inductor is below the capacitor, hot air rises, so more likely to heat up the capacitor, if they'd done it the other way around, it may have lasted longer, although being a sealed unit, it may have made little difference, it could be designed or planned in obsolescence , thus requiring a constant stream of buying replacements.
I have one of those old RadioShack desoldering irons with the squeezy bulb. It's the best as long as the tip is in good shape.
Cheap maker also omitted the MOV, which would extend the life of the whole circuit. Happy New Year Clive!
I bought 16 of these from Amazon about 2 years ago, branded as "Teckin". They work really well until they start turning on and off randomly and then refuse to come on at all. I tried to get one apart but realised that the case would be unsafe even if I repaired them. Only 10 of the original 16 still work.
Perhaps a "solder sucker" might be a useful purchase for desoldering?
There are fancy ones with an iron built into them, so you don't need three hands.
Big Clive has more experience than most of us combined and the skill to hold 2 things with one hand . He probably doesn't need expensive motorized tools like the one you suggest .
I have a wide selection of them, but don't always use them.
Those are mainly useful for (almost) desoldering ICs, and even then you have to go in with the braid to clean up. Just switching a single two legged component, it is rarely worth it unless the desoldering station is permanently set up.
happy new year Clive
and everyone watching
Watching at around 6:38…that is not how you make a Flux Capacitor Clive!
Sorry, I’ll see myself out for that one
I have lost count the number of capacitors I have changed to get things working again. I usually end up changing most of them once one has failed as they are either a) cheap, b) bad batch or c) both
Good video as always 👍
@13'10" comment about 'That pesky capacitor' made me smile....
...Bet the manufacturer smiles too, probably has a category for components that guarantee predictable medium term failure... maybe 'terminators'?
I find using ceramic tweezers with cut off sections of solder braid makes it easier to retain the heat in the braid (not using the rest of the roll as a heat sink), but for simple jobs i just do like you did.
I have 10 of these, quite useful. Long press makes it go into pairing mode. Tuya/Smart life apps, unless they are different variations.
Q: Is connecting an electrolytic capacitor backwards the only way to get it go bang in a most exciting manner...?
A: Oh, no. Dropping one of them into the molten solder bath of the selective soldering machine you're operating will do it quite nicely...
Couple million solder joints on record .. masterfully single-handedly doing the most difficult connections .. still wondering if it might go horribly wrong .. 😆
Yup, I bought a few brands of wifi smart lights. Two from the one brand I was testing failed. They all advertise 25000 hours with LEDs but that’s depends on the quality of the other components. For the VoColink brand they both failed with swollen capacitors.
To glue the plug together, I would dump a decent amount of baking soda in the cup, add a generous amount of CA glue to the perimeter of the backplate. Press the pieces together with the cup on the bottom, then invert it and shake gently. That would create a pretty solid bond.
When I opened one of these to re-flash the MCU to ESPHome, I found it didnt close up properly like you. I just wound some electrical tape around it between the pins and avoiding the holes, which seems to have held. If it doesnt, there is always the RCD under the stairs :)
I do love my 1kw mains 240v vibrating soldering iron for those big solder pads.
Most of my smart IOT devices are liberated from the chinese by reflashing the onboard esp or tuya chips with Tasmota or openbeken, they are now local Lan & mqtt controlled instead of the "Internet required Cloud" and are better to use. Multi relay devices are all on or all off by default configuration but once liberated you can control individual relays and have greater control over what is connected. I say goodnight to Alexa and it turns lights on and off as I go to bed (yup lazy as can be)
Liberated from the Chinese, and then you use Alexa.😂😂😂😂
dude, can you make a tutorial (series) for that sort of thing? Being able to actually use hardware that's been discontinued by the manufacturer and the requirement of their proprietary cloud service has rendered them useless, would be incredibly useful for consumer freedom and reducing waste.
... maybe big clive or perhaps Louis Rossmann can do that, if they realize it's an option - Louis would definitely love it.
@@TheDZHEX Tutorials already exist. search for "flash smart plug".
@@TheDZHEXflashing a no-cloud firmware like tasmota on any of these esp is quite easy once you figure out the pinning of the chip yourself or if you find it in the numerous documentation pages made by the community
While most esp8266/esp32 devices, and older Tuya devices are easily flashable with Tasmota or ESPHome (which I prefer for Home Assistant use since you don't need a separate mqtt broker) and many even have programming headers, newer Tuya devices like the LSPA7 use a proprietary microcontroller module that can't be flashed yet, even if you can get at the module. It's a shame really because these are cheap (I have a few) and unobtrusive, compared to something like a sonoff.
I had four unbranded smart plugs from Amazon that looked exactly like the ones you work on here. They all failed at the same time so I assumed a software problem. Found several articles on how to reset them but nothing worked. In the end I gave up & sold them on eBay as 'not working -- spares or repair'. I wonder if the buyer got them working.
For the to-link Kasa smart plugs it’s usually the relay that welds closed. Mine started to do this after a year. The temporary fix was to whack the smart plug on the work top and the contacts became free until next time. I did think of sending it to you but I couldn’t identify the miniature relay 🙄
"...pride comes before a fall ..." (8:14). Nope. "Pride goes before destruction, and haughtiness before a fall".
My pro-tip?, buy Sonoff switches, I've been running 2 x Sonoff S26 (eu type) switch sockets. Flashed with TASMOTA as soon as I got them, they've been working fine ever since, both are at least 3 years old and show no signs of failure, notably they all only have light loads plugged in, no kettle or heaters. I also have 8 other Sonoff based switches for ceiling/cupboard and closet lights, all are very, very reliable.
I had a couple of these fail. I ended up binning them as the case was buggered getting it apart. I wish I kept them now.
To be honest you can buy them for next to nothing now. I believe they are between £5-10. I kind of want to put one outside and shove an electric heater on one to see what would happen :)
I've done numerous repairs of low end gear involving similar caps glued to (or very close to) overworked heatsinks or coils... Pretty much guarantees the item survives the enthusiastic ''new-toy' period and fails when the user might be in the mood for another new toy.
@4:41 - I once saw a chap take a paper clip that touched multiple pins of low-melt and he was able to heat the paperclip and heat multiple pins at one time.
I have the same plugs, but branded as Athom plugs. I bricked one flashing the TASMOTA firmware. The internals are the same as this but with ESP
Happy New Year Clive! We love you!!!
Clive, My favorite type of video! Why was the failed capacitor exposed to high frequency? Was it not smoothing rectified mains voltage?
The 4.7 400v cap filters the mains 50hz. The 470 10v cap is filtering 1Mhz from the KP3211 switching chip.
Thankfully UK sockets are generally switched so if the cover of such devices comes away then we can isolate it.
Sideways glance to Technology Connections 👀
I use a lot of those WiFi sockets. (Yes I do a lot of home automation , because I a lazy git ) I wouldn't use a load above 10amps with them, mine are used for light loads such as table lamps ect. . Theses WiFi sockets are usually very reliable, I only had one failure in 10 years I've got 15 in use around my house , to be honest there cheap so repair is not worth while, but a very interesting video nevertheless