Not sure why everyone's complaining about this thing melting.... it was simply designed with a special feature called self-combustion... tsk-tsk Has anyone else notice how DiodeGoneWild uses some really funky unbranded measuring tools (volts and amp meters), yet gets the job done just fine? Proof that it's no so much the tools that matter, but the knowledge of using them. ;)
The voltage divider which makes 30 volt appear as 2.5 volt is the analog input of the ADC. Since the entire device draws only 5 mA while driving both the ADC and the 7 segments LED display, it is obvious that no resistor is needed, the chip does a good job regulating the current.
I learned a few days ago about zener stabilized power supplies. It was an unexpected surprise to see them in action here with all their drawbacks perfectly explained.
Looks like a test device, made for occasional use. I think it would even be OK if just used to check by a mechanic, and I can't really see any reason to run down the road with one plugged in, it would just be another distraction, especially when it catches fire as you are doing 80 miles per hour down the interstate!
You're right! But this guy is probably smarter than you and me put together... no joke! Trust me, once you have listened to his funny accent, you will crave it the next day like a drug. ;)
Holtek are PIC compatible. You'll also see 8051 controllers like STC, unmarked OTP controllers that are mostly PIC compatible, like Holtek or MDT, which might be clones of Holteks, and STM8 mirocontrollers in Chinese electronics. Usually, you can't justify an Atmel or PIC if you look even at STM8 pricing!
I use mine on a 12 volt battery for short periods only but I'll check the fuse and change it . Thanks for all your videos where you do a great job explaining and tracing out the circuits on switch mode power supplies.
I keep one of them little fellows handy in my glove box. Great fault finding tool in my opinion. It has just proved a massive help the other day when the battery light suddenly came on (turned out the alternator was not charging due to a bad regulator which is somehow integral with the carbon brushes in a Golf Mk4) and helped me determine if I could continue driving off the battery until I reached the next major place with an auto electric shop (I eventually could and had a voltage of 11.4V when dropping the car at the shop). No reason to keep it plugged in all the time, though, especially in cars where the fag lighter is always powered, regardless of which position your ignition switch is in.
Funny enough, LDOs are way cheaper in mass production as you get rid of two large solder joints and two thick pins to bend and trim. The bypass capacitors are required though, yet again, even in the present circuit they'd better put them in... Many cheap devices' engineers seem to be somewhat obsessed with shunts, even if mains-powered :)
It's not *just* a voltage regulator; it's also the precision voltage reference used for calibration. Seems a bit of a strange way around to do it, but there is actually a little bit of method behind the madness: the voltage actually gets more stable and accurate as more current is drawn, at least up to a point. It is fineà for 12V operation; and even for short-term use at 24V if you take care not to leave it running too long. Also, it's a nice, big resistor, so they knew it was going to get hot. I don't think this device would ever go completely on fire, unsolder itself or anything; the worst I would expect to happen would be for the display to soften and distort out of shape.
Mine (like a lot of peoples) was reading low at 11.8V for a 12V input. It had 1K and 15K resistors. I put two 1M ohm resistors in series (=2M) across the 15K resistor and now it is accurate. The 1K and 15K SMT resistors were actually very accurate and the 2.5V was also pretty much spot on. So I guess the problem lies in the processor chip - either wrong software or inaccurate AtoD ladder resistors inside the chip. However, when assembled, every time I connect it to a 12V supply I get a different answer from 11.8V to 12V. It seems to update once a second but not always gives the same answer.
Unless you have a run away voltage regulator in your car, plugging one of these into most modern cars is not going to hurt anything. Being they are actually for test purposes only, most people wouldnt bother leaving it plugged in anyways.
Once I had a runaway regulator in 2000 Skoda Felicia. The voltage went up to 20V and the battery was boiling and splashing all around. After replacing the regulator, the battery and all of the blown lamps, the car works again. Such a voltage meter would reveal the failure earlier, but having it plugged all the time may turn the car into a pile of ashes...
incroyables expériences vous connaissez DiodeGoneWild??? J'y crois pas! En attendant on est d'accord qu'on peut avoir ce genre d'objets en bien mieux pour un prix équivalent. English version: do Incroyables Expériences know DiodeGoneWild? I can't believe it!!! But still we all agree with that you can get this kind of items in much better version for the same price!
Yup. There is many normal trucks and suvs using 24v system like dodge ram trucks have 24v system cus of the large diesel engine it takes a crap ton of current in 12v system that's why they have 24v system.
I have a couple electric blankets that use that same screwed base. It draws higher and melts in the first hour of use. Common, and not good, design. Change the plug, all good again. I wonder if their market is one time use devices.
A low current fuse like 125mA has a high resistance, it can drop up 2V at 125mA, so it would affect the measurement too much especially because of the parallel voltage regulator.
The video is great, this digital voltage car charger is really good, I bought this renhotecic brand car charger not long ago, it's really good, if you need it when driving, you can prepare one.
Aliexpress item description: Note: Please pull out the device when you leave your car, do not use the device more than 2 minutes in 24V cars, or it will burn out.
No, in this case the linear regulator is better, the display does not need a lot of current. The reason it burns is that they chose a too low resistance. A buck converter is not very efficient at light load
This melted plastic remindes me of my small vacuum cleaner. I accidentally grabbed the wrong charger. I only looked on the polarity and the voltage but had one that can give 2 times the Amp. Was wondering whats smelled so strange and looked at my vacuum cleaner and there was a spot that looked like rubber and i touched it. It was hot but the vacuum cleaner is fine. Whats interesting is that i have a AC/AC plug. Don't know from which device i got this but i think it would be terrible to pick this plug, for devices that needs DC.
Noooooo, I've just bought same product to diagnose my car battery. Now I feel uneasy and unsafe, so thank you very much. On the other hand I just put it for few seconds before starting my car, also it is operating in 12-14v range, so no problem whatsoever. I'm still considering replace thing funky power supply it has with proper LM78XX variant. Should be an easy task, right?
I think the fuse is so big because a smaller one would have too high voltage drop on it. Despite that, I really can't understand why they used shunt regulator.
maybe this device is not supposed to work all time. Especially in 24V car. Just occasional use. This device is made for a short test of your car battery.
A legjobb autós feszültségmérő!!! :D :D :D :D :D Felügyelet nélkül egy kamionban és már gyullad is a fülke, alig pár milliós kár egy 1,5 dolláros kis szar miatt...
They're still on eBay today. You should get another and see if they've changed the circuitry and if not, show us how you fix it with a regulator. Do you need to add resistors to set the output?
Even a small linear voltage regulator like 78L05 would fit in that meter, and it would be significantly more efficient.. there's no need to have a switching regulator inside.
You know why it's melting? you're basically doing a torture test. Running it on 30v which is not so common in cars. Also, you're running it in an extended period of time. Normal periodic non continuous usage would be just fine.
It says it's up to 30V, so why not test it? In a truck or other 24V vehicle with the engine running, you normally have 28-29V. This is very close to 30V. And it's quite possible that people will leave it in the cigarette socket continuously. There's nothing to stop people from doing this. A lot of people actually want to have a permanent voltage display in their vehicle.
Yeahh that's not how you make a voltage meter. Good job China, yet another dangerously cheap product. If you really need to know the voltage in your car, get a smaller voltage meter with only LED display, circuit board on the back and two wires for power. They have voltage regulators built in, and sense voltage from supply voltage. Cut a small rectangular hole in your dashboard, fit the display through and use the two holes on the circuit board, some spacers (sold separately) and two M3 bolts and nuts to secure it, then connect to supply voltage. Easy, doesn't get hot, doesn't have a shunt resistor (because it isn't needed to sense voltage) and self contained. In fact, here's a link to the voltmeter described above: m.ebay.com/itm/Mini-DC0-30V-LED-3-Digital-Diaplay-Voltage-Voltmeter-Panel-Meter-With-2-Wires-HQ/222642267593?hash=item33d68365c9:m:mdAg26sJy4DzPFMQ88GqmWQ And here's a link to a fancier car voltmeter: m.ebay.com/itm/12V-Mini-Digital-Voltage-Meter-Display-Voltmeter-LED-Panel-for-Car-Motorcycle/273028120054?epid=595431268&hash=item3f91be7df6:g:N90AAOSwLjxaXj1l
I guess you could call it a car voltage melter...
That commend made my night [cause it's night here in India ;) ]
Not sure why everyone's complaining about this thing melting.... it was simply designed with a special feature called self-combustion... tsk-tsk
Has anyone else notice how DiodeGoneWild uses some really funky unbranded measuring tools (volts and amp meters), yet gets the job done just fine? Proof that it's no so much the tools that matter, but the knowledge of using them. ;)
Oof
You could also say you roasted them
It melts voltage!
The voltage divider which makes 30 volt appear as 2.5 volt is the analog input of the ADC. Since the entire device draws only 5 mA while driving both the ADC and the 7 segments LED display, it is obvious that no resistor is needed, the chip does a good job regulating the current.
I learned a few days ago about zener stabilized power supplies. It was an unexpected surprise to see them in action here with all their drawbacks perfectly explained.
But it continued to work. I would love to watch it till complete failure and measure thermal properties during the the process.
no
Looks like a test device, made for occasional use. I think it would even be OK if just used to check by a mechanic, and I can't really see any reason to run down the road with one plugged in, it would just be another distraction, especially when it catches fire as you are doing 80 miles per hour down the interstate!
your english sounds so funny. it sounds like if you are singing :D
I love the expressions he uses when he is amazed / scandalized.
-it's crazy....
-seriously guys?
etc ... kkkk !!!
You're right! But this guy is probably smarter than you and me put together... no joke!
Trust me, once you have listened to his funny accent, you will crave it the next day like a drug. ;)
@@Futinghe < Look, nobody's forcing you to listen to this... but if you wish to learn something new, it might be worth getting annoyed a little. lol
@@janracek894 he is Czech
@Seager < Well, once upon a time there was the greater Czecho-Slovakia, but since 1992 they've split into Czechia and Slovakia; :)
Car voltage meter with heating element.
Interesting combination.
Excellent!!... I get so tired of having to manually melt my cheap Chinese lighter-socket voltage-meters.. please take my money!... send me a dozen ;-)
Terry McKean yay its a plug and play burning device!
its fcking chinese.. copy everything.. communist *SUCKS*
The idea is to buy and make some modifications to it.
If you're to buy all components individually the total cost would be alot more expressive 😅
I've had one of these permanently plugged in my car for years and it's worked perfectly. Looks like it's best to avoid using on 24v though.
It's best to avoid Chinese junk.
I got 2 of them. That's a good video. I won't use it for long time. Put a switch on it. When not using the volt meter.
Even better, pull it out of the socket ;)
Should be safe in a 12v system
I put permanently on my car even when the engine is off, it is still turned on. I hardwired it and it is still working.
Put a 7805 before the resistor and you're okay.
The chip is a Holtek microprocessor :)
You're right. To this day I was only coming across ATMELs and PICs. By the way, this type of HOLTEK is OTP, so it is completely useless for hobby.
Holtek are PIC compatible.
You'll also see 8051 controllers like STC, unmarked OTP controllers that are mostly PIC compatible, like Holtek or MDT, which might be clones of Holteks, and STM8 mirocontrollers in Chinese electronics. Usually, you can't justify an Atmel or PIC if you look even at STM8 pricing!
Stm8 is very good, i use it to make sinusoidal inverters, with voltage regulation and protection, no problem at all
I use mine on a 12 volt battery for short periods only but I'll check the fuse and change it .
Thanks for all your videos where you do a great job explaining and tracing out the circuits on switch mode power supplies.
I keep one of them little fellows handy in my glove box. Great fault finding tool in my opinion. It has just proved a massive help the other day when the battery light suddenly came on (turned out the alternator was not charging due to a bad regulator which is somehow integral with the carbon brushes in a Golf Mk4) and helped me determine if I could continue driving off the battery until I reached the next major place with an auto electric shop (I eventually could and had a voltage of 11.4V when dropping the car at the shop). No reason to keep it plugged in all the time, though, especially in cars where the fag lighter is always powered, regardless of which position your ignition switch is in.
has an extra use.. after 30 v it's keeping warm your coffe
Lol
If it starts dripping plastic over your gear knob - You know you are having an over voltage event. Quite a good idea really.
Wow. Were they really too cheap to use a proper linear voltage regulator? It's not like those are expensive in China.
Funny enough, LDOs are way cheaper in mass production as you get rid of two large solder joints and two thick pins to bend and trim. The bypass capacitors are required though, yet again, even in the present circuit they'd better put them in... Many cheap devices' engineers seem to be somewhat obsessed with shunts, even if mains-powered :)
It's not *just* a voltage regulator; it's also the precision voltage reference used for calibration.
Seems a bit of a strange way around to do it, but there is actually a little bit of method behind the madness: the voltage actually gets more stable and accurate as more current is drawn, at least up to a point. It is fineà for 12V operation; and even for short-term use at 24V if you take care not to leave it running too long.
Also, it's a nice, big resistor, so they knew it was going to get hot. I don't think this device would ever go completely on fire, unsolder itself or anything; the worst I would expect to happen would be for the display to soften and distort out of shape.
Power dissipation would be the same!
That IC is likely some sort of microcontroller, made by Holtek.
Mine (like a lot of peoples) was reading low at 11.8V for a 12V input. It had 1K and 15K resistors. I put two 1M ohm resistors in series (=2M) across the 15K resistor and now it is accurate. The 1K and 15K SMT resistors were actually very accurate and the 2.5V was also pretty much spot on. So I guess the problem lies in the processor chip - either wrong software or inaccurate AtoD ladder resistors inside the chip. However, when assembled, every time I connect it to a 12V supply I get a different answer from 11.8V to 12V. It seems to update once a second but not always gives the same answer.
Unless you have a run away voltage regulator in your car, plugging one of these into most modern cars is not going to hurt anything. Being they are actually for test purposes only, most people wouldnt bother leaving it plugged in anyways.
Once I had a runaway regulator in 2000 Skoda Felicia. The voltage went up to 20V and the battery was boiling and splashing all around. After replacing the regulator, the battery and all of the blown lamps, the car works again. Such a voltage meter would reveal the failure earlier, but having it plugged all the time may turn the car into a pile of ashes...
Nothing quite like a good melty moment! (as BigClive would say.)
“5 amps!! Are you crrrrazy?” That part killed me. You could clearly him being astounded!
photoinduction channel comes to mind. always blowing up things
I had a rechargeable vacuum cleaner which had the same IC (HT46R47).
It's an MCU.
1:36 looks like a very interesting thumbnail for a video :)
Is there really usal car with 24V batteries?
Lorries and trucks often use 24v
incroyables expériences vous connaissez DiodeGoneWild??? J'y crois pas! En attendant on est d'accord qu'on peut avoir ce genre d'objets en bien mieux pour un prix équivalent.
English version:
do Incroyables Expériences know DiodeGoneWild? I can't believe it!!! But still we all agree with that you can get this kind of items in much better version for the same price!
I think trucks have 24V battery but its just named as car battery voltage monitoring device
Yup. There is many normal trucks and suvs using 24v system like dodge ram trucks have 24v system cus of the large diesel engine it takes a crap ton of current in 12v system that's why they have 24v system.
golf carts
0:55 The battery was literally boiling. I'm imagining some acid bubbling inside like some sort of sci-fi show.
That small chip is a microcontroller meant to measure voltages, amazingly small and cheap.
10:35 - I was about to cry.
HT46R47 is a 8 bit microcontroller with ADC
Chip is a HOLTEK 8-Bit RISC Microcontroller
I have a couple electric blankets that use that same screwed base. It draws higher and melts in the first hour of use. Common, and not good, design. Change the plug, all good again. I wonder if their market is one time use devices.
Cool voltmeter....with self melting technology..... Sounds awesome.
hahahah nice one, so far one of the best videos about cheap Chinese junk , I have seen.
you know its a hot item when it catches on fire!.
The chip at 11:30 is actaully a microcontroller built for battery charge detectors ...
www.ec66.com/market/sheet/HT46R47.pdf
A low current fuse like 125mA has a high resistance, it can drop up 2V at 125mA, so it would affect the measurement too much especially because of the parallel voltage regulator.
Drop 2V at 100mA? Then replace the resistor with a linear voltage regulator.
The video is great, this digital voltage car charger is really good, I bought this renhotecic brand car charger not long ago, it's really good, if you need it when driving, you can prepare one.
Wow. For some reason i can smell the plastic burning
Dobrá práce Číno.
some new cars dont has connected 12v connector directly to acumlator has got electronics and on this socket are allways 12v
Aliexpress item description: Note: Please pull out the device when you leave your car, do not use the device more than 2 minutes in 24V cars, or it will burn out.
"Ar u craizzzzeiy" This got me💀
You have made similar with pic's or atmels.
What a cheap way to make a supply :-(
I imagine a buck regulator would do a good job too.
No, in this case the linear regulator is better, the display does not need a lot of current. The reason it burns is that they chose a too low resistance. A buck converter is not very efficient at light load
Great demo.
This melted plastic remindes me of my small vacuum cleaner. I accidentally grabbed the wrong charger. I only looked on the polarity and the voltage but had one that can give 2 times the Amp. Was wondering whats smelled so strange and looked at my vacuum cleaner and there was a spot that looked like rubber and i touched it. It was hot but the vacuum cleaner is fine.
Whats interesting is that i have a AC/AC plug. Don't know from which device i got this but i think it would be terrible to pick this plug, for devices that needs DC.
Noooooo, I've just bought same product to diagnose my car battery. Now I feel uneasy and unsafe, so thank you very much.
On the other hand I just put it for few seconds before starting my car, also it is operating in 12-14v range, so no problem whatsoever. I'm still considering replace thing funky power supply it has with proper LM78XX variant. Should be an easy task, right?
i have the same the instructions are saying that at 24 volt use it only for 2 mins max
30v Max was probably meant as a top warning point as a quick disconnect point for you to unplug it. But I still wouldn't use it anyway
It can still light your cigarette while the plug is being used for the measurement. Win-win!
fine for short term use. I see no problem.
You can use a multimeter to measure the voltage through the lighter socket.
Ppl who drive trucks have enough money anyway. I only use it on my car in winter to see if battery is too low. Plug in, read, plug out. :)
I think the fuse is so big because a smaller one would have too high voltage drop on it. Despite that, I really can't understand why they used shunt regulator.
What happens if you have it on 24 volt but you dont disturb it? after many cycles will the plastic become really hard and brittle?
I had one of these on a 12V system and it lasted a few months..
It looked just the same inside.
I have one and works fine till now
I don't think this measures your car battery, only the voltage that is being regulated by your cars fuse box and cars wiring system.
aren't the digital voltmeter "modules" cheaper than this anyways?
the crazy fuse hhhh ; you make me laugh , u're right , its like " Car Voltage Meter gone wild" hhh
Where is the cat?
Another case where the device itself is the fuse.
maybe this device is not supposed to work all time. Especially in 24V car. Just occasional use. This device is made for a short test of your car battery.
Is chip component need a programming before use ?
They tend not to reset properly and indicate 11.1 etc after starting the car. Good and cheap but a bit annoying! Works after reinserting.
A legjobb autós feszültségmérő!!!
:D :D :D :D :D
Felügyelet nélkül egy kamionban és már gyullad is a fülke, alig pár milliós kár egy 1,5 dolláros kis szar miatt...
For such devices, can you show how to modify them to make safe & accurate?
Hi, every Skoda Felicia should have overvoltage alarm 😉
9:57 Satisfying
Did you said "74k" accidentally at 8:27?
They're still on eBay today. You should get another and see if they've changed the circuitry and if not, show us how you fix it with a regulator. Do you need to add resistors to set the output?
not that easy to fix. Unless you use a switching regulator
Even a small linear voltage regulator like 78L05 would fit in that meter, and it would be significantly more efficient.. there's no need to have a switching regulator inside.
5amps? are you crazy? i expected him to say "what the fuuuuuck" in accent :D
The meters in my home made power supply drop voltage through huge resistors... I'd like a more efficient way to drop the voltage.
You know why it's melting? you're basically doing a torture test. Running it on 30v which is not so common in cars. Also, you're running it in an extended period of time. Normal periodic non continuous usage would be just fine.
It says it's up to 30V, so why not test it? In a truck or other 24V vehicle with the engine running, you normally have 28-29V. This is very close to 30V. And it's quite possible that people will leave it in the cigarette socket continuously. There's nothing to stop people from doing this. A lot of people actually want to have a permanent voltage display in their vehicle.
What is hell who was the engineer to make that melting device 🙄
14.8v at 5 amps?
74watts before the fuse goes no point in having it the wires would melt before the fuse making it a few penny’s cheaper
11:00 the real liquid crystal
lol, it measures your battery while killing it due to the power it saps :D
First vid I saw from him😆
So we are all aware... this DOES NOT MEASURE THE VOLTAGE IN YOUR CAR because your cigarette lighter should be on its own fuse.
thanks for information
Hay,what in size a 7 segment????
CUSTOM SHAPED DISPLAY, CAN I BAY ONE?...
it's working as intended, it's plugged in a cigarette lighter so it still needs to light cigarettes 😊
It would be interesting to open a genuine Samsung or Huawei charger to inspect it.
DiodeGoneWild What type of car do you have?
So it is shody or super shody?
skoda favorit or skoda felicia ? i had the same issue with my 27 year old favorit, Czech cars are the best in the world !!
Self destruct enabled
Jak to mohou dávat do aut?!!
u or v ?
ty voe, jsi to vůbec nepochopil, to je voltmetr s vytápěním ;)
Asi si chce ohřát kafe
1:28 power suplyyyyyyyyyyy
Melty moments with dangerous cheap Chinese junk ^^
Are you Danyk ? Please I need to know.
Yes, he is. :)
Yeahh that's not how you make a voltage meter. Good job China, yet another dangerously cheap product. If you really need to know the voltage in your car, get a smaller voltage meter with only LED display, circuit board on the back and two wires for power. They have voltage regulators built in, and sense voltage from supply voltage. Cut a small rectangular hole in your dashboard, fit the display through and use the two holes on the circuit board, some spacers (sold separately) and two M3 bolts and nuts to secure it, then connect to supply voltage. Easy, doesn't get hot, doesn't have a shunt resistor (because it isn't needed to sense voltage) and self contained.
In fact, here's a link to the voltmeter described above: m.ebay.com/itm/Mini-DC0-30V-LED-3-Digital-Diaplay-Voltage-Voltmeter-Panel-Meter-With-2-Wires-HQ/222642267593?hash=item33d68365c9:m:mdAg26sJy4DzPFMQ88GqmWQ
And here's a link to a fancier car voltmeter: m.ebay.com/itm/12V-Mini-Digital-Voltage-Meter-Display-Voltmeter-LED-Panel-for-Car-Motorcycle/273028120054?epid=595431268&hash=item3f91be7df6:g:N90AAOSwLjxaXj1l
4:57 that looks like an inductor.
The big one is a resistor :).
The resistor was overheating
It works if u plug it in for a second
The way you smell 3:01 lol
What is about your free energy
"sree resisters" instead of 3 resistors