These circuit boards with a sequence of problems or odd subsequent failures provide fo much more to learn from and about. A simple identify the fault, fix it and send it out might may you look cleverer, but we'd be less the wiser. Warts and all 😅
Hi Richard, greetings from South Africa. I have found that sometimes the capacitor charge skews readings of resistors in circuit . Regards, thanks once again for sharing your time and expertise.
Once again very in-depth explanation of what's going on, much appreciated. I would wager that the battery basically enables the charger when plugged in and that you basically won't have any voltage unless the battery is connected and okay. Those PFC boost converter circuits are very unforgiving unless the mosfet is being commutated by the controller. Almost frightening if you asked me.
I now use a C210 for pretty much everything. Either one of the largest chisel tips JBC do, or a bent conical. Very versatile, if a little under sized for some of the things I ask of it.
If it's a decent charger then it should have current limiting on the output and a short circuit to the battery would be detected. If it doesn't have that protection it's the sort of setup that causes fires!
Good point, which gets me wondering if there isn't protection can some be added either on that board or with an additional one to run the output through. A stand alone protection circuit would be very marketable product.
Sir please help me where is the common ground plane n output circuit because there are many resistor capacitor and diode.transistor in output.but i confuse where to put black lead measure voltage in DC output of any circuit pcb as a return path.please help me sir this one
Hi Richard, I have just seen a review regarding The Fnirsi HRM-10 Internal Resistance Meter, see if you can get this meter to review, looks like it would come in handy for you
Heya, nice blown ic and a through hole in a resistor there should be something that is the cose of that. a oh a bad mosfet that could be the problem. hope you will get us updated about this in the future thanks
At college they taught us a few memory things to remember resistor code "Black beetles running over your garden bring very good weather" and a couple more racisty ones probably not pc these days.
Now we're intrigued. I feel for educational purposes, and given any applicable warnings, you need to tell us the other words. The more memorable the better 😊
who gve a f~ck about being PC? That is just some people who think they have some right to tell me what to think. I grant them no right to do so, and in return I will not tell them what to think. Fair is fair. So how this mnemonic goes Bill bloggs raped out young Gladys behind violets garden wall Black barstewards rape our young girls but vicars go without The British government taught me those in 1982 on a state sponsored electronics repair course so that must be OK
I don't know how you missed that Sir but the mosfet read 0.7something in the reverse bias of parasitic diode this meant the mosfet probably was faulty right?
Oops, I see you covered that later in the video, but I feel still important to point out for your subscribers who may have missed that point ? Cheers Cuan
The London Fire Brigade were called out to 155 e-bike fires and 28 e-scooter fires in 2023. They are calling for government action because 3 people died and 60 people were hurt.
This is one thing I would not fix, these batteries burn down your house with any help from yourself. One fixed you will be taking ownership of any battery fires because no one will be able to decide what the cause was. Did the battery have a defect or did the charger repair cause it. We all know the ebikes two states "burnt out" or "going to burn out".I rest my case😂😢
There's a user manual for that IC that suggests R33 (connected to pin 16) is typically 10k and there's a whole load of gobbledygook that talks about the current flowing into or out of that pin being sort of critical. This may be an entire shoal of red herring.
Or maybe I could just try yor suggestion 🙂 I'm quite interested to see if the PWM/PFC chip actually died or not. I do strongly believe that the mystery resistor coule be nowhere near as high as 10K or it would not burn up when the chip failed?
@@LearnElectronicsRepair Guesswork and speculation on my part, 330 ish volts across 10k (assuming IC short to ground) is 33ma 10.8W. Too old to get my head around what would happen if that IC didn't start properly. You may want to change the IC again, there is mention of a max current of 8mA into the HV pin.
@@ralphj4012 Yeah it is but like you say, that is assuming that pin 16 (HV) has a low resistance to ground which it most certainly will not have. Also the PSU didn't blow up until I attached the battery and powered it up again. Also the 4k7 resistor was not damaged. When I get the mosfets here I will of course replace the IC again, I have several more of them. I still don't know the correct value of the resistor on pin 16 but the typical application shows there is no resistor there and the original one had a hole blown in it which generally indicates a sudden surge of current rather than it baking slowly, so I really don't think it is going to be a very high value one. I don't know if the owner has any more of these chargers, I'll ask while waiting for the parts
Thank goodness for Detlef. I need one of him.
Yeah it is so good to have a friend like that 😉
These circuit boards with a sequence of problems or odd subsequent failures provide fo much more to learn from and about.
A simple identify the fault, fix it and send it out might may you look cleverer, but we'd be less the wiser. Warts and all 😅
Yeah that's what I think too 🙂
Hi Richard, greetings from South Africa. I have found that sometimes the capacitor charge skews readings of resistors in circuit . Regards, thanks once again for sharing your time and expertise.
Agreed. I mentioned that a charged capacitor (charged from the multimeter in diode mode) was messing with the readings of high value resistors
Thanks brother blessings
How about testing the battery with bench power supply ?
Once again very in-depth explanation of what's going on, much appreciated. I would wager that the battery basically enables the charger when plugged in and that you basically won't have any voltage unless the battery is connected and okay. Those PFC boost converter circuits are very unforgiving unless the mosfet is being commutated by the controller. Almost frightening if you asked me.
I’ve seen you and others successfully fix SMPS pwr supplies. Now, this kind of case is what I usually see, and give up.
OH I don't give up. I'm mostly just curious LOL
I now use a C210 for pretty much everything. Either one of the largest chisel tips JBC do, or a bent conical. Very versatile, if a little under sized for some of the things I ask of it.
If it's a decent charger then it should have current limiting on the output and a short circuit to the battery would be detected. If it doesn't have that protection it's the sort of setup that causes fires!
Good point, which gets me wondering if there isn't protection can some be added either on that board or with an additional one to run the output through.
A stand alone protection circuit would be very marketable product.
There may well be. I did not definitively prove the battery caused it to fail, it was just a possible guess
Nice one Rich.
Sir please help me where is the common ground plane n output circuit because there are many resistor capacitor and diode.transistor in output.but i confuse where to put black lead measure voltage in DC output of any circuit pcb as a return path.please help me sir this one
to test batteries and the internal resistance get the FNIRSI HRM-10 it does just that test betteries and the internal resistance
Thanks for the info
Hi Richard, I have just seen a review regarding The Fnirsi HRM-10 Internal Resistance Meter, see if you can get this meter to review, looks like it would come in handy for you
Hello. A little question. What is the purpose of glue underneath an IC? First time i have seen that
Heya, nice blown ic and a through hole in a resistor there should be something that is the cose of that. a oh a bad mosfet that could be the problem. hope you will get us updated about this in the future thanks
Saludos ingeniero desde Perú 🇵🇪 👍
How do you test a battery's internal resistance, Im sure I can google it, but was interested in relation to this video
At college they taught us a few memory things to remember resistor code "Black beetles running over your garden bring very good weather" and a couple more racisty ones probably not pc these days.
Now we're intrigued. I feel for educational purposes, and given any applicable warnings, you need to tell us the other words. The more memorable the better 😊
@@warwickbunn1250 I know one, Black Bo..................If you have been around electronics awhile you know the rest !! They were different times.
who gve a f~ck about being PC? That is just some people who think they have some right to tell me what to think. I grant them no right to do so, and in return I will not tell them what to think. Fair is fair. So how this mnemonic goes
Bill bloggs raped out young Gladys behind violets garden wall
Black barstewards rape our young girls but vicars go without
The British government taught me those in 1982 on a state sponsored electronics repair course so that must be OK
@@andymouse Only if we let them be different times. I'm old school and I rebel
@@LearnElectronicsRepair Yep, I'm 'old school' and I will always open a door for a lady.....better times :)
Is this the continuation of "HOW TO IDENTIFY A BLOWN CHIP PART NO"? 🤔
i remembered a few months ago you posted video something similar.
This is the continuation.
@@anthonyshiels9273 thanks. I thought so.
Yes. I linkled the original video in the description to this one
13:23 Shouldn't the MOSFET have read as open when measured in diode mode in opposite polarity instead of high-ish?
Yeah you would normally expect that in the polarity it normally operates
I don't know how you missed that Sir but the mosfet read 0.7something in the reverse bias of parasitic diode this meant the mosfet probably was faulty right?
It was an odd reading
@@LearnElectronicsRepair yes Sir regards, this is what I thought as well.
Have had funny readings before when my 9v battery was low around 7ish I think it was. Oops.
I would agree but I put a new battery in the fluke a couple of weeks ago (mentioned on video) and the Kaiweets was doing the same thing
Oops, I see you covered that later in the video, but I feel still important to point out for your subscribers who may have missed that point ? Cheers Cuan
No problem
Try it without the PFC mosfet.
Yeah that could be fun but I think it would not work as this IC is a combined PFC/PWM controller and one of the input pins monitors the PFC voltage. I
The London Fire Brigade were called out to 155 e-bike fires and 28 e-scooter fires in 2023. They are calling for government action because 3 people died and 60 people were hurt.
This is one thing I would not fix, these batteries burn down your house with any help from yourself.
One fixed you will be taking ownership of any battery fires because no one will be able to decide what the cause was. Did the battery have a defect or did the charger repair cause it.
We all know the ebikes two states "burnt out" or "going to burn out".I rest my case😂😢
Yep, squeak !
@@andymouse Hi Mr Mouse, i take it, it's getting cold enough to be on the Tube's
@@TheEmbeddedHobbyist Yeah getting that way !! :)
@@andymouse well looking forward to reading more of you. 😀 and maybe something from Fred
@@TheEmbeddedHobbyist :)
There's a user manual for that IC that suggests R33 (connected to pin 16) is typically 10k and there's a whole load of gobbledygook that talks about the current flowing into or out of that pin being sort of critical. This may be an entire shoal of red herring.
Or maybe I could just try yor suggestion 🙂 I'm quite interested to see if the PWM/PFC chip actually died or not. I do strongly believe that the mystery resistor coule be nowhere near as high as 10K or it would not burn up when the chip failed?
@@LearnElectronicsRepair Guesswork and speculation on my part, 330 ish volts across 10k (assuming IC short to ground) is 33ma 10.8W. Too old to get my head around what would happen if that IC didn't start properly. You may want to change the IC again, there is mention of a max current of 8mA into the HV pin.
@@ralphj4012 Yeah it is but like you say, that is assuming that pin 16 (HV) has a low resistance to ground which it most certainly will not have. Also the PSU didn't blow up until I attached the battery and powered it up again. Also the 4k7 resistor was not damaged. When I get the mosfets here I will of course replace the IC again, I have several more of them. I still don't know the correct value of the resistor on pin 16 but the typical application shows there is no resistor there and the original one had a hole blown in it which generally indicates a sudden surge of current rather than it baking slowly, so I really don't think it is going to be a very high value one. I don't know if the owner has any more of these chargers, I'll ask while waiting for the parts