The cheap Chinese bulb that won't turn off

  • Published: 05 July 2019
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    These LED bulbs will continue to draw power from the mains indefinitely even once they're switched off and the circuit is broken. But how?!

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Comments • 3 431

  • void main [void]
    void main [void]  1 days back

    Current induction ! Not capacitor !

    Fake science scam !

    • Jullian Mitsuo Miyamoto

      I know I'm a bit late, but since I didn't see anybody commenting this I'll say it...
      I'm a civil engineer, and when I project the electric installation, I make the neutral go to the light and the charged wire go to the switch, that prevents the circuit to be charged when the switch is off...

      • TVG28
        TVG28  2 days back

        Hammer: "Am I a joke to you?"

        • Sick Mick
          Sick Mick  3 days back


          • Josh Croy
            Josh Croy  3 days back

            Stuff large corporations don’t want you to know

            • Ichbims Derepep
              Ichbims Derepep  3 days back

              Him: This is dangerous *squirts water all over it*

              • Cédrick Katznetz von Ottobus

                I've got several 12m long chiness LED garlands in my rest room, and they remain slightly on even if I turn off the MAIN switch of the power strip.
                When I turn off ONE of the individual witchs of this power strip, then the correspondent garland turn absolutly off.

                • the amazing skeptic
                  the amazing skeptic  4 days back

                  You made an air capacitor

                  • Tayro Thinkingoutloud
                    Tayro Thinkingoutloud  4 days back

                    You can get the same effect by digging a 1' x 10' x 2' deep trench. salt the dirt you removed. place a copper and iron rod about 1/2" dim ea 6" apart with 1' salted filler under and over the rods. At one end of the trench connect to the iron, at the other the copper. This will only work like your zombie bulb as it has no transformer. Well depending on your geology. It may provide enough current. If you mount poles at either end to 15 + feet with wires running across then to load... That's how the original telegraph system worked before the invention of batteries.

                    • Anime Boy
                      Anime Boy  5 days back

                      It's called wireless electricity 😎

                      • Harold Smith
                        Harold Smith  5 days back

                        Interesting explanation, thank you.

                        What is the make and part number of the LED assemblies that glow due to sneak capacitance?

                        • sw4rmify
                          sw4rmify  6 days back

                          So this might explain part of it, but it’s not the explanation I’ve experimentally seen to be true. So here goes what I know:

                          Imagine you put two switches in the circuit. One of the switches is “upstream” (on the live wire before the lights) and the other is “downstream” (on the neutral, after the lights). Turning off downstream allows current to get to the lights and play around a little due to it being AC (particularly LEDs cause they’re diodes aka let current in one way but not the other) and you will have a glow. However if you turn it off upstream it cuts off everything underneath it. Apparently good electricians usually know this.

                          • EnderWin
                            EnderWin  6 days back

                            But you can't really say "indefinitely" can you? Afterall it's a part of the laws of thermodynamic

                            • Luka E-O
                              Luka E-O  3 days back

                              EnderWin no its still drawing power

                          • Sir SMKSAlOT
                            Sir SMKSAlOT  6 days back

                            lmao a capacitor, dude didn't even fact check this nonsense.

                            • Arnav Kumar
                              Arnav Kumar  7 days back

                              Bruh ...

                              • Erekose2023
                                Erekose2023  7 days back

                                Got an old LED lightbulb.

                                Worked fine for years. Recently it failled... except...

                                When I turned the cluster of 3 lights off to change it... the other two went out okay.. but the failled one now started random faint flickering for about 10 minutes.

                                Tried turning lights on... Two worked, failled one stayed dead... Turned the switch off.. working bulbs went out.. failled one flickers for about 10 minutes.

                                • qwer asdf
                                  qwer asdf  7 days back

                                  "Android is superior to iPhone...that's not contentious"


                                  • Fooks Lee Ho
                                    Fooks Lee Ho  1 weeks back

                                    My truck lights does the same thing stays on for full 10 min after I turn off the car so big deal your little light

                                    • El Visitor!
                                      El Visitor!  1 weeks back

                                      Really good video. Particularly love that he advises against messing with wiring for safety reasons and then appears to squirt water over the live extension outlet 😂

                                      • Bill Culverhouse
                                        Bill Culverhouse  1 weeks back

                                        We had a cfl bulb on a 3-way switch that would flash (attempt to light) every 15-20 mins after it was "off" I suspect something like this was the culprit. Haven't noticed it with LED bulb replacements though.

                                        • tmastersat
                                          tmastersat  1 weeks back

                                          It won't do that if the house was wired according to code.

                                          • Xkaku xkaku
                                            Xkaku xkaku  1 weeks back

                                            Chinese tech if way too advanced

                                            • Nellie Rutten
                                              Nellie Rutten  1 weeks back

                                              You need a switch that cut both negatieve and positive wires.

                                              • yvrelna
                                                yvrelna  1 weeks back

                                                I'm guessing that these bulbs are intended as a component for use in other electronics, where they expect you to supply any additional wirings to prevent this issue from happening as needed, and they're not for consumer use. That's probably also why they don't have Edison mounting (or other similar consumer level mounts).

                                                • Fady Samann
                                                  Fady Samann  1 weeks back

                                                  Currently, Edison is winning because of renewable energy is relying on DC.

                                                • uRiBiTo666
                                                  uRiBiTo666  1 weeks back

                                                  So, basically, the wiring in your house becomes a super inefficient and pointless wireless charger.

                                                  • juma W
                                                    juma W  1 weeks back

                                                    In iraq I mean most of it. We people don’t setup group wire so we have this problem. Always on

                                                    • wiadroman
                                                      wiadroman  1 weeks back

                                                      If you threw a magnet into this you could start selling it as a free energy device.

                                                      • call of duty mobile
                                                        call of duty mobile  1 weeks back

                                                        English plz

                                                        • electronic DIY
                                                          electronic DIY  1 weeks back

                                                          I noticed years ago(like I read in a comment YouTube later) the CFL bulb remained flashing slightly in dark even though it was switched off, does the circuit oscillator stores a converted energy which causes the small bulb flashes?

                                                          • Lunar
                                                            Lunar  1 weeks back

                                                            *_round and round and round and round and round and round and round and round and round and round and round and round and round and round and round and round and round and round and round and round_*

                                                            • phthalo blue
                                                              phthalo blue  1 weeks back

                                                              Did we just discover pereptual energy???

                                                              • Ivan SP
                                                                Ivan SP  1 weeks back

                                                                Me: *pick up a sledgehammer* “Imma do something called pro gamer move” *start smashing the bulb *

                                                                • void main [void]
                                                                  void main [void]  1 weeks back

                                                                  "In LED bulbs, depending on the circuit arrangement, the induced current is manifested by a low luminous persistence of the bulbs while the circuit is open" according to Wikipedia ! The electromagnetic field induce current via coupling that LED"s can transfer into light

                                                                  This is false information ! Fake Science and racist

                                                                  • Hans Dampf
                                                                    Hans Dampf  1 weeks back

                                                                    could you please not mention this awful edison guy?

                                                                    this man need to be erased from our books...

                                                                    • James Films
                                                                      James Films  2 weeks back

                                                                      Physics: Wait. That's illegal!

                                                                      • Clement Jason Villeneuve

                                                                        if by pure luck of design.. a house is wired in a way which would make the house a kind of box that accumulate and discharge electricity in all the randomly occurring capacitor, and somehow, the rest of the wiring and material in the house would act as the circuit board... do you think that your house could become some kind of automates ?, and could that close loop system accumulate and amplify its energy to interfere ,kill or harm,or whatever, on something biologic ????

                                                                        • larry jackson
                                                                          larry jackson  2 weeks back

                                                                          I think the answer to why that one particular led bulb will glow when the other one doesn't is the amount of electricity that one bulb uses to get it to glow. A microwatt compared maybe a full watt or two for the other bulb. In other words, the coiled wire capacitor will only hold or allow the disturbed electrons to release a micro amount for the flow of electrons. That one type of glowing bulb will operate at a low glow with a lot less amount of electricity. Perhaps a new type of light with extremely low electrical impulses to produce light.

                                                                          • Mr.PICKLES !!!
                                                                            Mr.PICKLES !!!  2 weeks back

                                                                            That's what I'm bringing during an apocalypse

                                                                            • AI fan
                                                                              AI fan  2 weeks back

                                                                              induction im guessing

                                                                              • void main [void]
                                                                                void main [void]  1 weeks back

                                                                                "In LED bulbs, depending on the circuit arrangement, the induced current is manifested by a low luminous persistence of the bulbs while the circuit is open" according to Wikipedia

                                                                            • Tim Q
                                                                              Tim Q  2 weeks back

                                                                              Correction: if the British used a 110v system instead of 230v this also would not happen. So you were wrong when you said it doesn't matter how much voltage is applied.

                                                                              • Robert Johnson
                                                                                Robert Johnson  2 weeks back

                                                                                Dude you have no idea what you're talking about, a coil of wire can only act as a capacitor when its wound around a ferromagnetic core, except that we already have a name for that, it's called an inductor. But either way what's happening there is that the bulb is acting as a passive rectifier, which means that when one side of the two AC phases are removed, it still has the first, which also explains why the brightness decreases by almost exactly half. Not only that but the still connected phase is still switching on and off, completing one half of a sine wave, which means that every time the phase switches, it momentarily induces a small voltage in the opposite phase, which allows it to act as a current return path.

                                                                                • void main [void]
                                                                                  void main [void]  1 weeks back

                                                                                  "In LED bulbs, depending on the circuit arrangement, the induced current is manifested by a low luminous persistence of the bulbs while the circuit is open" according to Wikipedia

                                                                                  The electromagnetic field induce current via coupling !

                                                                              • Pieter Vrugteveen
                                                                                Pieter Vrugteveen  2 weeks back

                                                                                neutral bleed, try grounding your system a little better.

                                                                                • NootNoot
                                                                                  NootNoot  2 weeks back

                                                                                  The thing is. All our bulbs are doing that. But old wired or gas bulbs don't glow at that low current. Leds do. And that's why many people notice this effect.
                                                                                  For led installations it's good to have the switch directly at the output so the cables can't induce each other.

                                                                                  • Sandy Kumar
                                                                                    Sandy Kumar  2 weeks back

                                                                                    EMF BY EMI( Electro Magnetic Induction)

                                                                                  • Phil Rant
                                                                                    Phil Rant  2 weeks back

                                                                                    Very interesting but what is an Android?

                                                                                    • Paul Dogon
                                                                                      Paul Dogon  2 weeks back

                                                                                      Mine also glow after I tun them off but only for a couple of seconds

                                                                                      • jeffrey arthur
                                                                                        jeffrey arthur  2 weeks back

                                                                                        With those gloves, there would be no ElectroBOOM!