Chinese LED lamp rated 30W. Seriously?
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- Опубликовано: 3 июн 2018
- This time I took a look at (and into) a "30W" corn LED light bulb from China from Ebay for 3 USD. Can this really be 30W? Is it safe to use? I made some measurements and tests with my wattmeter, multimeter and oscilloscope.
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you need chinese measuring instruments to confirm the watts.
-anywhere from 5 to 50 watts- , lets call it 30
@@km5405 i would not be surprised if thats what they did 🤦♂️
And analize why's says 30w but is 5w
Hi diodegonewild, I love your vids, you are an amazing RUclipsr, keep up those hobby electronics
Thanks! I will do my best to keep up ;)
that power rating probably means it replaces 30w incadescent bulb
That is was I was also thinking
thats not that great actually
It's 30 China-watt ;-)
To convert real watts to China-watts, you have to multiply it by a number that gets a bit higher every year...
I think it's 9 Chinawatt. This is 30 Chinachinawatt.
It's like Mexican minutes, but in reverse, since they are on the opposite side of the globe :p
It's manufactured in the same factory that makes those 9000 mAh li-ion batteries.
9000 mAh Li-ion batteries are outdated. I saw a 10500 mAh one!
Also, 4200mAh Ni-MH AA batteries...
Its an easy formula to get the real numbers coming out of China. Just drop the last Zero.
Thank me now, or thank me later.
Great content, very clear step by step process. I understand more things in electronics now, with you, that back then in secondary school (30 years ago, technical institute for computer science, electronics classes in the first two years). Thanks for sharing.
Same here
New subscriber here. I am from New Jersey, USA. Your voice and your handwriting is why I subscribed, in addition to your great content. Keep up the good work.
it's really appreciated when you make these videos more educational. always looking forward to your videos
That is really very *DANGERUUUUUUSSSS!!!!*
Dodgyyyy
*EVEN MORE SALTTTTTT!!!*
I can smell something BERNINGGGG
Your accent is so funny! Love your vids dude! Keep up the great work! Love you
upvote for cat :)
love the calculator, a real blast from the past.
It's Privileg 825 MD from 1975, with a VFD display :).
Love your videos. Thank you for uploads.
Thank you very much for this sharing video. I like the way you analyze the object, your diagram and also the suggestions for improvement. Today it will be useful for me to try to fix the same bulb.
I really appreciate how thorough your videos are; the amount of effort that you put in really shines through!
Do you think the ambient lighting made the flicker less visible to your eyes, or do you not even perceive any flicker in a darkened room? The reason I find this strange is that the flicker from LED lamps with insufficient smoothing or current linearization circuitry really bothers me a lot. It is especially bad at the 100Hz harmonic that we have here, but I also tested a few lamps at 60Hz mains (which gave a 120Hz flicker, that I verified with a photodiode connected to my 'scope), which was still very visible and annoying, especially if there isn't any other sources of steady illumination.
I have found that the dead-time when the LED is off is the most important variable (apart from the frequency, of course), with lamps that switch off completely for a part of the input waveform being much more 'flickery' than lamps which only dip down to 10-20% of their maximum intensity.
However, even with the best examples that I have, of the latter type of lamp (its brightness oscillates at 100Hz, around 70% of it's maximum amplitude, from 100% down to a 40% minimum), the flicker is still annoying enough that I simply can't use it as the only source of light in a room (there can be multiple types of LED bulbs installed in the room, but since they all flicker at the same frequency AND in phase with each other, the flicker doesn't diminish at all).
I think that 100 or 120Hz should not be visible to human eye, as long as you don't move your eyebals rapidly or don't observe fast moving objects. On moving objects, you may see strips or dots. But without much motion, you shouldn't perceive 100-120 Hz flicker. What you may perceive is a flicker of some remote control systems transmitted via mains. I sometimes see it too, but it only happens randomly (usualy for 1 second every time the remote signal is transmitter). ... The higher the frequency, the brighter the light has to be for you to see the flicker. But above about 90 Hz you shouldn't see any flicker no matter how bright the light is. You may still perceive moving objects as dotted or striped, especially when the light dips down to nearly zero.
DiodeGoneWild; Ah you're right, I was throwing and catching a ball to see if the lighting would have any effect.
I think what you are referring to is called the 'flicker fusion threshold', which indeed is only valid for a completely stationary (or very slowly changing) image.
The annoying part is, even when simply reading a book (where the 100Hz flicker is completely eliminated, I still get really bad headaches after 45-60 minutes, which I don't get at all with incandescent lighting.
It seems similar to the effect in computer games where slow movement at 60fps seems fine to me, but fast motion (such as in Counter Strike) still gives me bad motion sickness, even at the maximum refresh rate of my monitor (144Hz).
I would have expected that gaming motion sickness would be related to sea-sickness, but I only get motion sickness when I am playing a fast-paced shooter myself.
Maybe there's just something wrong with my brain's processing of motion and other people don't seem to care about temporal aliasing, because they simply don't experience any negative effects thereof?
Different people probably have different sensitivity to flicker. I'm totally not bothered by it, but some people may be affected by it. The solution probably is to use LEDs with a better smoothing. Especially the higher power LEDs with a buck regulator tend to have much better smoothing. Low power LED (like 3W) tend to have a capacitive dropper and a poor smoothing so they are cheaper. CFL's are generally smoothed well because the self oscillating inverted doesn't run properly without smoothing. And tungsten lamps have a low flicker because of the thermal mass of the filament (especially the high power ones or the low voltage ones with a thick filament).
I can notice the flicker, it does bother me somewhat. I think it depends on the person, and perhaps even their age? (Like how old people can't hear high frequencies as well. I'm 21 and can still hear up to about 20kHz or so.)
I can confirm, I notice a flicker of a cheap LED Lamps and Its very annoying for me.
I like the new graphics you used in this video. Good job.
Its good you talk about the flickering problem. 👍
The 100 Hz flickering (or 120Hz flickering in other countries) is advantageous in some cases such as speed controlling of record players. I use a flickery LED bulb I screw into a desk lamp to do this with a record player I use to convert vinyl records into audio files. In some record players there are neon lamps (or led lights) built in right next to the strobe pattern of the turntable but not in the one I have.
Thank u VM for this detailed explanation
Keep up the good work. Best wishes from Northern Ireland.
as always your job is great thanks a ton
love it!
took out the trouble from learning experimentally. ♥️
when he says "are you kidding me guys??" I falled down as always when he says that lol
then he says "special self-melting feature", I pissed on myself 🤣
Keep the good content up DiodeGoneWild! Always a lot to learn with you😉
Diode gone wild you have so many vintage devices . cool.
Hi bro, I love your English. The videos you make are really interesting.
Before I didn't like ur channel because of ur accent
But now its getting better
Good job
In 2023 he still has the exact same accent. It's the reason that most people watch his videos!
Useful video
Fantastic video like always!
thanks :)
seeriuslyy?!
Edgars Lacis-S 😂
Edgars Lacis-S 1 mega oooooohm
Ok. Ive been walking around immitating his accent for hours. Big awesome accent, and the tone goes up at the end of every sentence lol. Its musical almost. Iove it!
Few years ago I mistakenly bought these lamps. Fortunately they didn’t work long so I could hange them to better ones. You have new informative style which looks good. Wonder how laborious it is.
The black case of this bulb looks nostalgic, just like the old bakelite
Thank you for your videos....can i ask you?where are you from?
You mentioned that you have to use isolation transformer because the scope is grounded. IF you connect the ends to the grounded scope what will happen?
When energy saving fluorescent lightbulbs came on the market, they also put the comparing ordinary lightbulb Wattage on the package so people could choose the right replacement bulb.
Could it be that the 30Watt means that it compares to a 30Watt ordinary lightbulb??
I like your videos, very interesting and informative. Love your sense of humor.
Hi thanks for the video. Allways informative. I do have a question and could you please answer. How do you get your cheap yellow multimeter to give out the watts rating while measuring in the voltage range? Thanks in advance.
danyk.cz/wmetr_en.html
I heard that rumble, and I was like, "he's got a weird cat."
Will you make some videos about radios?
The oscilloscope made in CCCP (SSSR). I remember that :)))) We used to used them.
did you push it to 30 watt already?
Hi dear @diodegonewild , in 11:35 you mentioned improvement to the distorted waveform, how did you actually do that sir.?
By adding another 1uF capacitor directly to the output of the isolation transformer.
Really man, you should make a billboard saying "Another cheap fine product from Dodgyland"
Wait.. You're from Czechia, right? You mentioned a "Czech power chord extension" in one video.
Your video are great
I have two questions
Why is the current a sine wave shouldn't it be a dc voltage accros the resistor
How can you measure the power with a multimiter thank you
Replying to a very old comment... The current drawn is the current drawn... it's fluctuating/pulsing DC (always positive, but changes voltage repeatedly). Basically, an AC waveform but not going positive / negative in reference to zero volts.
The LEDs only conduct when the voltage is high enough to illuminate them. Since there is only a tiny output smoothing capacitor, the voltage is not smoothed... the LEDs are literally switching on and off at rectified mains frequency (100Hz).
You cannot measure watts with a multimeter. He built a power meter which uses that cheap multimeter as a display. The details are on his website.
'Are you kidding me gaaais?!'
lol like it
can i change smd led by resistor
Your old oscilloscope videos help with my Russian lessons too: "время на деление".
I love when he says "Arre yoou kiddiing mee guyyyys?" :D
Diode will you make a lightbulb at your own?
Is there any vid about this watt counting splitter? :o I'm interested into!
Not a video, but I have a webpage describing what I've put inside :)
danyk.cz/wmetr_en.html
I very much like your review. It’s thorough and informative. Such reviews are rare.
Keep it up. How come you have Russian instruments? Going by your delivery style you don’t sound Russian
1:09
*Special feature*
Are you kidding me guys 😂😂😂😂😂
mayby equivalent to a 30w incandesant?
I don't know why, but at 3:55 to 4:05, the sound of the thunderclap and a clock ticking in the background at foreground volume made me think of the scene in 101 Dalmatians just before Cruella DeVille comes bursting in through the door.
Informative, interesting, educational, and the accent is entertaining too, love it, I’m just waiting for a good catch phrase.... 🤩🤪🤗
Watch any of his USB charger videos. The catch phrase is "Super Dodgeeee"
I enjoy your detailed and informative videos. Off topic... Ever grow catnip for your cat? One thing I have noticed is that there are 4 sockets on the left side of your large power strip that appear to be crossed off with green ink. Is there a story as to why?
Thanks :). I never grew catnip. Should I? :) Those crossed sockets are not in use. I removed the contacts to make enough space for the wattmeter circuitry that's built into it :). The power strip now contains this circuitry:
danyk.cz/wmetr_en.html
DiodeGoneWild have you sealed off the unusable sockets so it is impossible to get into contact with your circuitry?
You know what you can and cannot do with this power strip, but others who may want to use it at some point will not.
Excellent.
Little, tecnical question :P, what country are you from, and what's your mother tongue language?
How u connected the multimeter to diplay the power
The power strip has this built into it:
danyk.cz/wmetr_en.html
Are you kidding me guys?
Ahh......yes
Im dying 😂😂😂😂
Cringe
What are this 2 capacitors are doing in this circuit ? What would happen if there are no this 2 capacitors?
Replying to old question. The first capacitor is termed a "dropper". It is acting as a current limiting resistor, and does the same thing as a resistor except that it doesn't waste power or get hot.
Then the circuit has the bridge rectifier, which converts the (current limited) mains voltage into a rectified (pulsing) 100Hz DC. The second capacitor is supposed to act as a smoothing capacitor. So it should store enough power during the "low pulses" of the cycle to run the LEDs, which would prevent flicker.
However the capacitor is thousands of times too small for that task, so it does almost nothing to reduce the flicker. Since the voltage is so high, they must use a 400V rated capacitor in that position... Space limitations and cost means that they cannot fitthe 100 or even 1000uF capacitor which would tame that ripple and flicker.
The circuit would operate exactly the same without the second (electrolytic) capacitor. However it must have the first input capacitor or there would be no current limiting and the whole thing would explode instantly.
Thank you for nice explanation..
Are you kidding me Guuuuuuuuuuuuuuuuuys ????!! You're The best DGW !! Greetings from Algeria.
AC caused flickering right?
lol 30 watts :-D, perhaps it gives out the light level of a 30w incandescent bulb?.
it's a shame you don't have two identical bigger double bobbin transformers to assemble a double primary transformer.
It would still have losses but slightly less than you have now.
Poor puss, they freak out at thunder/lightning :-(
I think it's not incandescent watts, it's Chinese watts :). I plan to buy some proper isolation transformer. I have 200VA one, but it's vintage and the isolation is made of paper, which may have been deteriorated and so the safety of it is questionable. I'm probably gonna buy a new one, about 50VA, enough for most LEDs and chargers. The cat doesn't care about thunders, but the dog is quite scared.
You could/should test the isolation of the old one. The most primitve way would be a small voltage doubler from the mains with a series resistor or small bulb and connect this between primary and secondary if you do not have access to an isolation tester.
What is then ratio between Chinese (LED) watts and equivalent incandescent watts? I estimate this is closer together than a factor of two, at least closer than to the real LED power consumption.
It´s always helpful to look for other listings of the same LED lamp when you order from china.
For example, I bought some "8W" LED filament lamps that turned out to be 5.2W (8.6 VA), but many other sellers listed it as 16W.
If you have the money, spend it on a larger isolation transformer, perhaps 1kVA or so. It would come in handy for repairing stuff (anything from TVs to power supplies and as you said, LED lamps, etc..) when you need to isolate it in order to not short out the mains with your oscilloscope. (Obviously you have to be careful not to shock yourself too, but the ground isolation helps reduce that possibility.)
If you get one with a center tap, or even two separate secondary windings, that would be even better because you can use it to buck the mains voltage to 120V if needed.
+DiodeGoneWild Do you have a variac? If you do, you can get a 400V to 230V transformer and use that as your isolation transformer. They seem to be more common and cheaper than pure isolation transformers.
Could you please point us to a video where you explain how your make-shift power meter works? Is there a schematic shown in any one of the other videos that you use it? provide a timestamp in the video to find it easily.
The information is on his Website (link on About page)
Oh man u got the good old Tools xD
1.00 "bloody hot" lol ....self melting feature ....GOLD!!!
From where are U?
There is a different version of this lamp from Foxanon with a black led PCB which supposedly uses a constant current driver to avoid flickering. They even provide a picture of the PCB to show the difference compared to your version of the lamp. I have purchased a few of them and so far I could not identify any flicker or interference with the phone camera. I would really appreciate if you could analyze the difference with this model. There are a few sellers, but if somebody wants to check them out just go to eBay and search "E14 E27 Led Corn Bulbs 4020SMD Light Lamps" (international product search). By the way, if you check the product description you will notice that 30W is the equivalent CFL power for the same lumen output, not the actual power (Chinese marketing at its best).
Can you show us how to make your watt meter? Please it seems very useful
It's shown on his website. However it's easier to just buy a wattmeter.
You can make it run at 0.5 watt and use it as night illumination
8:22 сделано в СССР
да, походу он сидит в совке
Awesome video as usual, you can report it to eBay with the proof of the wattage it really is and get your money back and keep the bulb
I sometimes do this, but this time I missed the 60 days...
buy it another, reort to ebay measurements and so you have the entire bulb and money back:-)) and so you can put a bad feedback to this vendor
DiodeGoneWild Oh ok, I love your videos, would it be alright if I download all your videos to put into my archive in case something ever happens to your channel? I really love your style of making videos and your humor as well as electronics, if not that's fine too, but I would like your permission.
excelente amigo
Dear dany, please make a video on your yellow watt meter. WITH SCHEMATIC PLEASE ❤❤❤❤❤❤
bro any simple way to identify the phase sequence of three phase supply
Hello, here's a schematic I reverse engineered from an old tester:
danyk.cz/reverz19.html
The neon lamp lights up for A-B sequence, but not for B-A sequence. The ground can be connected to earth/ground or neutral or to a pad you touch with your finger.
pamiętaj bracie
Tej lampy żółtą poświatę!
Thanks for the videos and measures with scopes. 100 Hertz is not flicker to human eyes, but if you want flicker try almost burn incandescent tubes + poor starters. Otherwise use cellphone camera. How do you smooth the resonating frequency of the two transformers? Maybe with a snubber network?
Thanks :). I've put another 1uF capacitor directly in parallel with the output of the transformer and the voltage was suddenly a nice sine wave :).
I like your voice, it's unique. 🤣🤣🤭
with 20 mA per led it can run at 8 watt. which seems kinda high
Hey Diode I think it's about comparing light amount to "normal"wire bulb. That's what I'm thinking :)
It's not :). The sellers deliberately multiply the power by a number that gets higher and higher...
How do you measure power with those cheap meters in Dc voltage mode?
It must be a shunt but how you get DC voltage??
@@mrroronoa8 wondering the same
You don't. You build a Wattmeter, and use the cheap multimeter as a budget-priced LCD display.
The circuit is on his website.
May be is equivalent to 30 W with under driven led for less power dissipation, maybe.
Looks about equivalent to a 30W incandescent bulb... which is what the seller will probably claim you were supposed to think.
unappreciated channel :D
1:12 special feature is soldering iron feature :)
3:55
i love storms
I also love storms, but recently a lightning destroyed my wifi router and its 5V power supply. The power supply even smelled burned! I wanted to take a look inside, but luckily I didn't. The internet company replaced it for free :).
Why do you have to use those transformers? What would happen if not?
Nobody replied, so I will... The transformers are wired as a 240:240V isolation transformer. This means that neither of the "output" wires are connected to the house's mains wiring. So, whilst there is about 240V AC between those 2 wires, neither of them has any connection to the ground (earth) which is where the Neutral of your home's wiring is referenced.
In a single-phase supply like in Europe, your house is actually only wired with ONE mains cable which supplies 240V AC. The second return wire is via the earth (dirt) back to the power station. Hence why if you touch the 240V mains, the current flows through you and out of your shoes.... and that hurts.
The isolation transformer also means that he can connect the oscilloscope to the circuit. This is needed because the black "ground" clip of the oscilloscope is grounded to earth. Any current that passes through that connection will blow up the oscilloscope, so you cannot measure AC mains with a standard oscilloscope. It needs to be a "floating" ground that won't provide a return current path.
So, the purposes of the 2 transformers is to create a single transformer where both leads have absolutely nothing to do with the original mains. In this way, whilst there is power available between those wires, there is no way it can flow from those wires to either mains Live or mains Neutral (earth).
Thanks!
How to measure watts?????
You can't measure Watts, You have to calculate them with "P=U*I"
I have this circuitry built into my power strip:
danyk.cz/wmetr_en.html
it's a wattmeter. Actually a power to voltage converter, so the power can be displayed using a cheap voltmeter.
DiodeGoneWild thanks for replying
Hello DiodeGoneWild.... It is realy right, that the Inrush Current at the Start Moment ist too high.
I have many of this cheap LED Lamps that also have the same Circuit. But they are all dead after a half year.
Can you Help me to find a maching Resistor for the Current Limitation at the Start ???
Or can you explain it at your example as you would dimension it ?
THX....
I think you make very good videos, becouse you can make such technically good explantation, with you such simple means.
Good LED lamps usualy contain a fusible resistor which works both as an inrush resistor and as a fuse. It mostly tends to be something from 10ohms to 100ohms. For safety, it should really be designed as fusible, which means that it fails in a safe manner (no fire, no short circuit...). The power rating of this resistor usualy is 1W in LED lamps.
Make video on home theater that turn on with stand by circuits
Soviet union education (school) :)))
You are italian or hungarian?
Most likely czeh or slovakian
ciao, I like the way where you show/analyze the things .. well job .. I waiting that you analyze the power supply because is the same that are used the my 3d printers .. greetings from Italy ;)
wow! I live the stone age calculator!!
It's Privileg 825 MD from 1975. It was probably a great privilege to have a calculator back then!
Full bridge rectifier
man, i like your content, but the sound quality is kinda meh, i hear a lot of distortions in my headphones and so i actually have to use equalizer to cut all the high sounds. something like zoom or taskam recorder should work for you if you can afford them. anyway, thank you for your videos.
It looks like a vacuum tube rectifier
Nice vintage calculator from 1974!
Nice grenade
ebay. your Aliexpress shipping
Perhaps itsbrightness is equal to 30watt bulb not the consumption.
Equivalent to a 30W incandescent lamp in light output, so of course that is the rating they put on there.
Maybe you're right.
Some lamps, sold in Chinese stores and made in p.r.c., to respect the European rules, declare power consumed and lumens generated: they are more correct quantities to define the functionality of a lamp regardless of the fact that the values can be increased for marketing,
Nope. If you say its 30w not "eqquivalent to 30w". That way its misleading advertisement, and thus maybe even could result in some legal actions.