I am a little disappointed, expected the Silver cover to be connected to the the screw socket. Maybe they could add this feature to make it even more dangerous.
I was expecting a non-isolated power supply in contact with the metal cover or, at the very least, sharp edges that could cut you while handling rhe lamp. Totally disappointed.
I used to service the walmart fishtanks in my part of the country. It was a very robust and good system if run properly. Alot of my calls were for the uv lamp disinfection portion. Poorly trained managers didn't use the included clean gloves they sent with replacement lamps. So of course they failed very quickly, then i got called in. The funniest one i did was drive 4.5 hours to troubleshoot the tank lighting that wasn't working. I went. And signed in. Went and found the pets manager. Sure enough the lighting was in fact not working. I opened the service panel, (which you have to do to do a water change, it's user serviceable, the gfci the lighting was plugged into had gotten slightly damp during a water change so it tripped. I reset it, closed it up, signed out of the store, and drove the 4.5 hours home. All billing hours. To press a button.
That's like the many IT stories where the caller insists that their desktop/tower computer isn't working and won't turn on and when someone comes to investigate the problem, they discover the caller has been turning the monitor off and on instead of the computer, which turns on just fine (and probably only turned off due to a short power outage). So the caller is charged a service call fee for the IT service person to just push a button.
Many of us have been there. That's corporate for ya. Sure wouldn't want any employee to have two braincells available such that they might generate an independent thought. (And the pool of potential employees largely from an "education" system disincentivized to teach "how to learn" and instead focused on "shut up, don't ask questions, just pass the test so that you'll become a good serf" and on things not related to education.) Oh, well. At least it was billable, hope the drive was nice.
@@matthewellisor5835 it's new brunswick canada. With 85% of our terrain being forest. Nice drive? Well it just all looks the same, was it unpleasant? Not at all. Its pretty to look at, just a bit boring is all if you travel often by land vehicles. It was early spring, and i brought my puppy with me for company. So it was a good drive. Nice to have someone to talk to. Even if they don't understand you, or talk back. Haha
I once drove 10 hrs (one way) on an emergency service call to a trucking company that we had installed an RFID lock on the trailers roll-up door ("door won't open, but a few inches")... got there to discover the recent snowstorm had collapsed the roof of the trailer, preventing door movement...
Did a version of that in our church office, one of the ladies let out some bad words.... I think the priest got a far bigger shock from her, than I would have - assuming I didn't fake it.
@@hyperboloidofonesheet1036 (edit: original post fixed) I had a project involving a cap storing approx 50J, almost the size of a soda can, and I was really really careful around it when system was running... and I locked it inside a very sturdy metal box tucked away behind a safety gate. I was not intrested to find out what that cap would do to metallic objects near its phat screw terminals. I used it to assist switching of solenoids/contactors, the point was to switch them very "decisively" but use a lower hold voltage to prevent heat build up.
3:37 I agree. Fingering lamps isn't a good idea. 1. You might get your fingers in the socket, which could hurt, and 2. Lamps can't tell you whether they like it or not.
So, Clive, this lamp is not only germicidal, but also a homicidal and expensive to run. Excellent. How are you going, post-COVID? I hope you are fully recovered. 👍
Clive got the Chinese chixken flu? No that dudes so tough and smooth talking and great at reining and talking via rolling everything how. Can China gentlentouch germ get him? Lies I say.
I had that happen exactly once. I had no idea I had injured my eyes until it hit me on the drive home. I had to drive for an hour in absolute misery while not being able to see because my eyes were watering so badly. Mostly resolved by the next morning, though.
You know your going to be miserable when white lights start to turn pink in your vision. I've had arc eye also from welding with a mask that had a corner of the dark glass broken off and gone. I had no idea that I had hurt my eyes until on the drive home from work during the night. The headlights of all the oncoming vehicles started turning pink, then red, then the pain slowly started coming on. It was a miserable night, and part of the next day, before it started getting better.
In ancient times we used these clothes dryer germicidal lamps to erase EPROM memory chips, the kinds with quartz windows. they quickly became unpopular once flash memory came out.
@@Okurka. - Thus the reason their popularity rapidly plummeted after the introduction of the newer, easier to use stuff. That's the sort of time-line one would expect, no?
Exactly! Woke up in the middle of the night with sand burning in my eyes and it was "pain level 10"... I'd rather not say how I got into this mess. But your description is SPOT ON. Signed Dum Arse
I've worked with welding at school, before I graduated. I never once got arc flash from welding but I know what it feels like to have dry eyes that feel like they have sand in them.
The case looks like its been designed to hold a "real" power supply with the cooling vents. I guess changing iits use to a fancy LED chandelier might look interesting with the refelctions off the the Aluminium..Whats good for us to see is not really what you want your family buying and getting more than a little tingle from.
It reminded me of the time that i was trying to fix my friend's cheap hi-fi that just died and wouldn't power on after an intense party. I took it apart and started to remove the internal power supply which was a properly built switching power supply, and then i got the worst shock i ever experienced from a smoothing capacitor after the bridge rectifier (so around 325 V DC). The most shocking (pun intended) thing is that the device was sitting unplugged for many hours before i started taking it apart so this suggests absolutely no discharging resistor which was insane. I then shorted it with a screwdriver and it made quite the bang. From now on I'll always check and discharge any capacitors that possibly can be at high voltage levels.
I once repaired a friend's CRT tv that would not turn on after the power off. The owner told it would be ok the next day. So I powered it up and turned it off. Sure enough, it was dead after that. The power supply was a printed board by itself, so I carelessly had it removed but got nasty shock from the big capacitor. Immediately, I realised what caused the problem. The resistor that connected across the capacitor had gone very high value that unable to discharge the voltage. Replacing that resistor solved the problem.
I always assume that capacitors in a PSU will be charged up. I keep a 1 k ohm resistor which I apply across big electrolytics (via insulated tweezers). For similar reasons (though safety of sensitive components rather than my body) I always press and hold in the power button of a PC power supply after unplugging it from the mains, to let the capacitors discharge through the case and CPU fans) - I do that before, for example, unplugging a hard disk drive.
Early in the pandemic some of the "experts" were coming up with the "new" idea of using UV-C to clean the air. To which one doctor who went into field clinics for the WHO said, "yeah, we use those all the time". But most amusing was looking at the history of use, it turns out that in the 1930s, UV-C was used to prove that viruses could be airborne, and thus great advances for measles mitigation. But also that UV-C was effective against airborne viruses.
@@nickwallette6201 There was some research into a specific section of the spectrum that our skin would tolerate well enough and doesn't result in ozone production. Sticking to mostly that wavelength seemed to inactivate many virus particles in the air but good luck getting the quality control right on that with unknown replacement supply chains inevitably messing it up somewhere. I don't remember if it was eye safe or not, the skin can take quite a bit but uh eyes are probably a little bit more sensitive. Would give you the link but I trashed all those bookmarks a while ago when paywalls started going up again, there was a nice period where many publishers would make the covid related articles freely accessable and that went away at some point last year. And it's been too long ago to remember the specifics like what the title was, which wavelength and publisher.
@@nickwallette6201 Seems like my reply didn't show up (yet?). I did link to the website of a podcast so maybe it's being witheld for manual approval or automatically removed. I eventually remembered that it was brought up in episode 666 of "this week in virology". Throwing "twiv 666" into your search engine of choice should get you to the episode notes that contains a link to both articles and a timestamp when they discuss it. Alternately if you directly want the articles you could search for their titles: first one, "Far-UVC light: A new tool to control the spread of airborne-mediated microbial diseases" second one, "Far-UVC light (222 nm) efficiently and safely inactivates airborne human coronaviruses" The first article is a pre-pandemic one focused on various things, the second one being newer and more coronavirus focused.
@@nickwallette6201 The wands with the mercury vapor vacuum tubes in them are powerful enough to kill the virus at close distances. But, I DO have to laugh at the wands with 8 or so LEDs in them... One being a low power UVC LED, and the rest just plain blue LEDs. 😆
In addition to the potential stress on the lamp of that "minimalist approach" (which may or may not be an issue, I'm not sure), one of the other big issues with that design is that the electrical spikes it generates aren't only felt by the bulb: This design would be extremely electrically noisy, sending spikes back down the power transmission line to anything else connected to the same circuit, and producing a lot of EM interference for surrounding equipment as well. This could cause lots of problems for any more sensitive electronics you happen to have plugged in nearby, such as random glitches or crashes for digital devices, or audible hums in audio outputs, etc (or for things like some sorts of wireless communications in the area).
Holy crap that snap was like a fuse blowing. Thankfully you did answer my question though about adding a discharge resistor. Just seems the manufacturer was too cheap for such extravagant things like safety.
He explained recently, that sometimes people send their designs off to be built in China and they figure out how to build the same thing cheaper, often by using less parts, and supply them like that.
I wonder if the UVC will break down that plastic ring in the otherwise all-aluminum chunk. That seems like a weird design decision. Though, taken in the context of the rest of the lamp, I guess it's on-brand. 🤷♂️👍️
The fact that most things come from China sort of escapes our mind at times. Republicans like to drum up war to distract us from an orange cult taking office
Yes, they're seen in the USA with far different (presumably safer) driving circuitry, usually potted in silicone. I can see why you might expect the envelope to go black from sputtering of the filament but that wouldn't affect UV emission from the flat front face of the tube, which in the examples I've seen is where the UV is shone into the space to be sterilized. Nor would there be much blackening as the coating is partly intended to reduce sputtering, and the filament doesn't stay hot except for a brief time when starting. None of that diminishes my "oh shit" reaction when seeing that... "circuitry".
Well, that's a fine bit of DeathTech. And made with nothing but the highest of manufacturing and engineering standards, naturally. Fun for all, young and old!
Germicidal x-mas lights haha! I have nosy neighbors and thought on occasion about an (UV) decoration light. Look! Pretty bleu light! Watching your uv and ozone adventures puts bad thoughts in my head.
Say Clive, you may want to check your schematic ... The lamp physically has the capacitor connected between neutral and the hot side of the bulb socket. You drew it like someone thinking might draw it, not the way, either ignorantly or maliciously, a Chinese engineer had it built.
This reminds me of my past time servicing microwave excited mercury vapor UV lamps for the semiconductor industry. The microwave energy itself was not "energetic" enough to elicit the UV producing reaction from the lamp; an exciter lamp very similar to the one in this video, was employed to provide the photons needed to get the lamp to light. They were horrible, with visible bubbles in the envelope, but were magnetically ballasted. They failed frequently which I blamed on the bubbles in the quartz envelope. The main lamp was a quartz bulb, rotated in a constant blast of compressed air for cooling. They would fail spectacularly, with a loud explosion ruining the reflector from impacts of quartz fragments at high velocity. Where did the mercury go? Into the atmosphere, I'm afraid. Somebody likely touched the bulb without gloves again. Not me.
Those sound similar to the microwave excited sulfur lamps and the tiny tic-tac lamps with RF excitation used in some experimental entertainment industry lights.
I can imagine the "warning" on this thing would be something like; "Kindly use the upmost caution when operating the lamp. For it creates a massive dose of the Ultraviolet A B and C. Use of gloves to handle lamp. Use isolated screwdriver to ensure proper discharge when upon servicing."
If you do the math, the capacitor works in a constant current generator configuration. The resistive variation of tungsten, from ambient temperature to reddish glow, is 1:10. Therefore, the voltage across the filament become ten times higher, and that is when the barium oxide coating close the circuit and emits UV light. I did the I / V curve with a Variac, an ampermeter and a voltmeter. The lamp needs desperately a 1 Amp fuse in series with the capacitor, and a 2.2 MOhm resistor in parallel with it. Thank you for all your efforts ! Highly appreciated...
At the start of the pandemic I considered getting one of these to help sterilize my bedroom while I was out of it during the day, but I realized 1 there are sooo99 many spaces the light would never reach, and 2 I didn't want an ozone buildup in the place I sleep, but 3rd I looked into these cheap lamps too and realized they were capacitored cheaply and just knew one of us would hit lit up like Thor after a few beers, and that was the end of the thought.
Well I am an old fart now but I have been following you for several years. I have to say I find some of my best ideas while learning from your videos. My daughter needs to use one of those breathing masks at night while she sleeps. It has always been quite a chore to keep it all clean. She watched some of those commercials on buying a cleaning machine for them and one day asked me if I could figure out a cheap way to build such a device. I thought back to one of your videos on this UVC bulb so I went online and purchased the clear U shaped bulb. I took a regular glass type light mount and screwed it onto the lid of a plastic bucket. The bucket once held kitty litter so the top was half mounted all the time to the bucket. I screwed onto the side that was always inside. I interrupted the cord going from the plug to the socket with a 110 volt rated toggle switch. Now when she gets up, the mask and hose go into the bucket. The lid is closed and she turns on the switch. That wonderful smell of ozone comes from the bucket and about an hour later the mask and hose come out smelling ever so fresh and clean Sure the stuff is washed once or twice a week but not daily as she used to have to clean the product.
That is a rather clever way of designing a gas discharge bulb, I like it. Would have been nice if there were more kinds, like CFL or neon or something.
Well now Clive, yet another top notch expose. I never tire of your coverage of these Uv gimmickyzeugies. And what is a most rewarding bonus, are the most fascinating people and comments that your page attracts. Cheers!
I've never really paid attention to the wiring on E27 holders or almost any lamp socket for that matter, of course I tend to put the neutral wire on the screw part but since most floor lamps and things like that have a standard (european) plug that fits both ways into the socket so either one could be live and the thread seems to be recessed enough so that you have to be pretty deliberate if you want to touch the thread while screwing it in Of course in this case it's a bit different since the wiring flips between the holders I recall having a desktop plugged into a non grounded plug at my parents house (which I know you shouldn't do) and I used to get tingles from the metal case which wasn't grounded due to not having a ground and flipping the plug the other way solved it, I'm guessing it's just a bit of leakage current flowing through me? I also got a buzz from the aluminum bits on my keyboard
I'm pretty sure that the instructions for those floor lamps (at least those with proper documentation and a legit CE declaration that actually holds its promise) say that you are required to unplug them before changing a bulb. (In practice, almost nobody does that, I know.) That's just one of the disadvantages of non-polarized plugs.
"This lamp can hurt you in two ways." Knowing some of the devices featured on this channel, I'm thinking UVC plus shock risk. Now to watch and find out! Wow, it's even worse than I imagined. No resistor across the capacitor, saving maybe $0.02 per unit.
They were probably saving more with the labour. It's a bit tricky to put a resistor across this huge axial cap. The resistor's own leads are probably not long enough, they should have extended it, and put heat shrink on it. Or they just could have ordered custom 1M resistors with extra long leads, but the heat shrink would still be needed to prevent a short with the E27 thread. They chose the simplest "solution" instead: "F it, it works without that resistor!"
I purchased some of these a couple of years ago and used a 4mf power factor correction capacitor salvaged from a 20 watt flourescent lamp fitting. These are intended for direct connection across the mains.
Oh my... So once upon a time I worked at a science center as an exhibition tech (best job ever) and some high voltage with a wimshurst generator and a cf bulb.. it lit up neatly via the wireless transmission of power. I did not know the circuit inside was not diode protected... I'd have peed my pants and dropped the bulb if I could when I was bit thru the bulb threads....
One of those metal halide store lights gave me a nasty surprise you're talking about, here. I guess there was no discharge resistor across the capacitor that was inside. But it was, indeed, meant to be "permanently" connected, not with a plug, like the way I was using it. Still, should probably have some kind of safety discharge resistor. Thanks for posting!
i have the same light, only look at it through clear acrylic for safety, but they dont seem to work, did the banana test for 10 min no change on skin color, while doing the same with philips TUV PL-L 36W makes drastic change in only 5 min
Interesting as always, but got me thinking... Many reptiles get cataracts and issues from lighting. Halogens seem to generate very different amounts of UVA, UVB and probably UVC. Maybe one day you can measure actual outputs to give us an idea what we might be doing to our little captives. Of course different reptiles need different lighting and are sensitive to different lighting... Lush jungle vs desert vs cave. I remove glass lens to get UVB, but after your excellent video I fear there could be UVC. My Crocodile Gecko actually doesn't need UVB, so I switched out to LEDs. Cheers 🍻
We had a pressure washer that basically did the same thing when I unplugged it if I wasn’t concentrating when I wrap up the power cable I used to get a nice hand flinching tingle off the pins on the plug.
I used to have a 120 volt AC fixture that provided a combination of UV and IR simultaneously, centered around a mercury vapor discharge. [That combination is good for causing human skin to produce vitamin D.] Inside the open-faced unit there was a large-ish glass tube (about 1 inch diameter by 5 inches long) with filaments inside at each end, plus a few drops of mercury visible inside, and coiled resistive wire (nichrome) wound onto ceramic supports at each end of the glow tube. An open cage of welded wires across the face prevented easy access to the dangerous bits. When power was first applied and the external heaters were cold, more power went into the internal heaters, getting them hot enough to strike an arc at low current in the rarefied mercury vapor at room temperature. As the tube warmed up, more mercury vapor was evolved from the drops of mercury, and current increased. Color of the glowing vapor also shifted. Gradually the current would rise until the external heaters got enough current to glow reddish-orange, which also meant the tube had minimal voltage across it then. Unfortunately I did not measure the changing or static voltages or the overall current, but I can say the entire fixture was both old and of low mass, so it did not have any magnetic or solid-state ballast inside. Instead it used resistive ballasting, via the external heater coils. As a result, it presumably had decent power factor, since much of the load was resistive. Again, not measured by me.
Wouldn't that be problematic in other ways too? Big cap able to put voltage on the line for anything else that may be sharing the same power circuit? Was expecting something more like a ballast circuit inside the lamp.
i bought a 25watt UV-C bulb (ozone edition) last year and used an adapter to fit it in the bedrooms central light socket. the mold in the air was quite bad. Running the bulb made the whole room stink. Ran it for the suggested 15 minutes then vented the room for an hour it smelt worse than a swimming pool full of chlorine but the mold an toxins had completely gone, could once again breath properly the filament in mine is completely different it has a coil of thick metal wire inside the bulb like an induction heater but produces a lovely blue tint like yours did. £40 well spent id say
I had a hoover once that if you grabbed the mains plug after unplugging, it would give you a jolt,i think it must of been a suppressor cap in the hoover input circuit.
That capacitor inside is used as a tension divider and also prevents DC bias. The capacitor is Polyester film capacitor type and It is most commonly used in household products. The build charge on the device is not a problem and can not harm if permanently wired on the power grid. The problem occurs If the device is plug wired and portable, indeed. On the other hand I prefer UV light bulb over chemical deterrents for killing germs.
Capacitors are fun. I worked security for a while, some got handsy to plea, other got angry. 'Sorry, I cannot break the rules.' I decided to make two silver stripes, attached to a 300v capacitor, that ran down my sleeve. Had a nice charge button off a 9v in my pocket, in the case someone was extra annoying, or to catch someone off guard.
@@davelowets Ya missed the part where it charged up a 300v cap. I had a multiplier circuit that made the strips not friendly to the touch. 300v is still not very much, but it's enough to divert attention long enough for me to react to hostility. _And it was fun to have people test it._
After finding a need for a new bedside lamp, I noticed quite a few very pretty ones that have USB outputs on the base and touch response for very low prices. I wouldn’t be surprised if a variation on the cheap pink charger guts were just wedged in there as £19 for all this seems near impossible. Maybe there’s some opportunity for you there Clive.
Taking a charge from a big cap is something. I had a motor cap zap me once and for me it was much more painful than residential AC mains. Granted mains is more dangerous due to the AC characteristics, it still hurt like hell.
@@revbobuk as a kid I used to go to the local photography store and asked for discarded disposable cameras with flashes. Then I took it apart, soldered wires to the capacitor and superglued a piece of bicycle inner tube to my hand and had contacts on that and hid the wires inside my sleeve. I also added a switch there so I could easily control for how long I'd charge the capacitor. Usually only went for few seconds and it was still a pretty good zap when I went to my friends and shook hands. When overdoing the charging it actually hurts all the way to the shoulder for quite some time and burns the skin :)
In my younger years,i have experienced ark eye ! i wouldn't wish that on anyone ! i was glued to someone welding and was enjoying the blue light (albeit to close) no problem until 1 am and it is as Clive puts it,it is like someone pouring sand into your open eyes ! ever since then i can't even watch someone welding on TV and i look away ! be warned !
Nice shocking hazard you got there! BTW I have a capacitor which is 13000uf at 500volts, surely if you would touch that when fully charged you would get a chock big enough to make you glow like that UV bulb lol
@@elietheprof5678 indeed, I actually blew two 240volt light bulbs when load testing the power supply I built where that capacitor is used in and it can actually just by that charge supply over 100 watts of power for way above 10 seconds. Not even Electroboom would play with such cap. The “Ripple current” rating is over 20 amps on it and I dare not even think of the short circuit current ha ha. I love that cap
@@trevorc4413 would be better fitting here to compare by joules. a typical camera flash has around 5.4J (@120uF & 300V). Those 4 uF are equal to 0.22J @ 330V. But also many other factors matter like the internal resistance of the capacitor (and thus maximum discharge time -> maximum current). A defibrilator for example is charged to 150-360J. So no serious damages from camera flashes, just pain. Also got shocked by one a couple of times. those "single use" cameras a great for building mini coilguns
@@Xenon777_ yeah these shocks can be pretty nasty. wouldnt do it on a daily basis lol. always be careful around higher voltages (>50V AC, 100V DC). When working with those voltages, make sure to be extra careful. principles like "one hand behind your back" for example (so you cant possibly close the circuit through your whole torso).
I am quite shocked (intended) at the voltage discharge across the plug pins. What a flash and crack as the point of the screwdriver head touched the Live pin... Nasty indeed. I'll have to remember if I must handle one of these UVC emitters to short-out the plug pins just in case I get ZAPPED.
Wouldn't that capacitor be extremely hot after a few minutes as it's being loading with so much current 50 times a second and just bust it's electrolytic nut prematurely and in turn shortening it's service life?
The capacitor is only holding voltage; the lamp itself is very very low power. Plus you may be thinking of a resistor in series with a high-current circuit, it indeed might get hot.
@@georgegonzalez2476 ok cool. Thank you for that. I'm still learning so I appreciate being corrected so I can learn about the stuff I don't know, which is a lot haha
When covid struck, I bought a whole bunch of them bulbs. Nobody could tell me how simple to put just a large capacitor in series so they all died once I had bound matching sockets. Erasing EEproms was also on my mind but the applications have become rare.
I often get quite a shock off the end of OnePlus dash/warp phone chargers, I assume they have a capacitor in them that's not discharging much like this lamp. It's weird as you'd expect better from a proper manufacturer.
In North America we use 120 VAC/60Hz. Both the voltage and line frequency difference would make the difference for the capacitor. I believe the Xc at 50 Hz for the 4.2 uF cap is equivalent to approx 770 Ohms. Looks like the manufacture of that lamp was too cheap to add a 1/2 Watt 1 Meg Ohm resistor across the cap to discharge it. I would use a 470 K resistor to discharge it faster.
One upon a time I picked up a very expensive HP RF Vector Voltmeter. I grabbed the mains plug to save it from dragging on the ground and got a decent shock from the plug and nearly dropped the instrument. Wouldn't have been a good look so early on in my career. As for this lamp it seems very similar in its design to the self ballasted mercury vapor lamp except the envelope is quartz glass with no phosphor.
I remember a Zenith TV that used to hold the capacitive charge when unplugged. The bleeder resistors in the switchmode power supply must have failed in that particular TV. Nasty surprise, indeed.
Clive, could you consider a video on what all the numbers on the hopi mean? Well... I suppose mainly the power factor. Is it just a measure of electrical "wastage", so hitting as close to 1 is good? Similar to how PC power supplies have the 80+ bronze/silver/gold/platinum scores?
Hi, electrical engineering student here! I'll see if I can help explain. In short, Power Factor is a measure of how far out-of-phase the voltage and current sine waves are, with values closer to 1 being more in-phase (and thus "wasting" less power). At the cost of some hand-waving, we can consider inductors and capacitors to be "resistors" in the imaginary plane. This means that resistors consume "real" power and capacitors (and inductors) consume "imaginary" power. If we graph the power consumed, both real and imaginary, on the complex plane, we can find the hypotenuse of the triangle formed. This is called "Apparent Power", and always has both a length AND an angle (because it's a vector)! But writing "800kVA angle 35°" is a pain, so we shorten it with power factors. The power factor is just the cosine of the angle of the apparent power -- in other words, the ratio of the magnitude of the apparent power to the magnitude of the real power. But that's not quite enough, since cosine is an even function (plugging in -45° and +45° has the same result). Thus, we need to add the word "lagging" or "leading". Leading means that the circuit is more capacitive, and the voltage "leads" the current. Lagging means that the circuit is more inductive, and the voltage "lags" the current. Since this particular death trap is almost JUST a capacitor, it's almost all imaginary power -- which leads to the very, very low leading power factor.
Does anyone else other than me remember the combined infrared and ultraviolet lamps that used to be around in the possibly 70's? I'm willing to bet as much UV C came off as A & B. It was like looking into the sun (I was only a kid & knew no better) My dad used to spend ages sat in front of it, back to it as I remember.
My parents had such a device and it somehow always creeped me out. I only used the infrared part of it when I had a cold. (Ours allowed to select UV + IR or IR only)
I remember my mother having one. The smell alone told my young self it was dangerous. When I got older i realised it was chirning out dangerous levels of UV and a fair whack of ozone. It had a weirs bulb in the centre for the UV and 2 'bars' for IR i think all in a metal case that folded shut.
I am a little disappointed, expected the Silver cover to be connected to the the screw socket. Maybe they could add this feature to make it even more dangerous.
Nah, you're demonstrating how that cover is exactly where one might expect the danger. They're opting to shock _and_ surprise.
That could actually happen if the socket was bent a little more so that the screw part of the bulb came in contact.
All Christmas trees hurt you - in the wallet.
I was expecting a non-isolated power supply in contact with the metal cover or, at the very least, sharp edges that could cut you while handling rhe lamp. Totally disappointed.
When I see metal on bigclive, I assume it to be live.
I used to service the walmart fishtanks in my part of the country. It was a very robust and good system if run properly. Alot of my calls were for the uv lamp disinfection portion. Poorly trained managers didn't use the included clean gloves they sent with replacement lamps. So of course they failed very quickly, then i got called in. The funniest one i did was drive 4.5 hours to troubleshoot the tank lighting that wasn't working. I went. And signed in. Went and found the pets manager. Sure enough the lighting was in fact not working. I opened the service panel, (which you have to do to do a water change, it's user serviceable, the gfci the lighting was plugged into had gotten slightly damp during a water change so it tripped. I reset it, closed it up, signed out of the store, and drove the 4.5 hours home. All billing hours. To press a button.
"poorly trained person does xy" seems to be the new normal in retail
That's like the many IT stories where the caller insists that their desktop/tower computer isn't working and won't turn on and when someone comes to investigate the problem, they discover the caller has been turning the monitor off and on instead of the computer, which turns on just fine (and probably only turned off due to a short power outage). So the caller is charged a service call fee for the IT service person to just push a button.
Many of us have been there.
That's corporate for ya. Sure wouldn't want any employee to have two braincells available such that they might generate an independent thought.
(And the pool of potential employees largely from an "education" system disincentivized to teach "how to learn" and instead focused on "shut up, don't ask questions, just pass the test so that you'll become a good serf" and on things not related to education.)
Oh, well. At least it was billable, hope the drive was nice.
@@matthewellisor5835 it's new brunswick canada. With 85% of our terrain being forest. Nice drive? Well it just all looks the same, was it unpleasant? Not at all. Its pretty to look at, just a bit boring is all if you travel often by land vehicles. It was early spring, and i brought my puppy with me for company. So it was a good drive. Nice to have someone to talk to. Even if they don't understand you, or talk back. Haha
I once drove 10 hrs (one way) on an emergency service call to a trucking company that we had installed an RFID lock on the trailers roll-up door ("door won't open, but a few inches")... got there to discover the recent snowstorm had collapsed the roof of the trailer, preventing door movement...
*Touches the conductors*
"yep, it's discharged"
Never gets old
Did a version of that in our church office, one of the ladies let out some bad words....
I think the priest got a far bigger shock from her, than I would have - assuming I didn't fake it.
I don't want to see it happen but I imagine a very decicive "uhhh, no, it was not"
That's called the Electroboom method of testing. :-)
Some people who touch the contacts to check if it is discharged also never get old…
That was bigger spark than I expected...
Up to 0.25 joules. (edited; my mistake for switching mF and µF)
I jumped quite a bit more than I usually would with this.
@@hyperboloidofonesheet1036 (edit: original post fixed) I had a project involving a cap storing approx 50J, almost the size of a soda can, and I was really really careful around it when system was running... and I locked it inside a very sturdy metal box tucked away behind a safety gate. I was not intrested to find out what that cap would do to metallic objects near its phat screw terminals. I used it to assist switching of solenoids/contactors, the point was to switch them very "decisively" but use a lower hold voltage to prevent heat build up.
@@Paxmax You are correct. I used mF instead of µF.
I was expecting a tiny little crackle, not a taser. He wasn't joking about the zap.
"i wanted to make Christmas lights that can hurt you" - Clive is one industrial accident away from becoming a batman villain
Germicidal Christmas lights ! 😆😅🤣😂😄
He's not the villain we deserve, but he's the villain I want.
"Holy UVC Batman! what is Big Clive up to now?"
@@railgap Internet Hat-Tip! (I don't just give those away, y'know...)
hes already got the maniacal laugh down
3:37 I agree. Fingering lamps isn't a good idea. 1. You might get your fingers in the socket, which could hurt, and 2. Lamps can't tell you whether they like it or not.
😂
I don't want to take such remarks from a socket, that is forked on a basis.
sus
I once wired up a computer IEC cable wrong when i felt that back of the power supply i tripped the breaker and had a sore finger for a week
He sets ‘em up, we nod ‘em in. 😊
"A potential source of surprises" . So well said.
Thanks for quoting
I had the same thought!
Modern humor, it's so baah.
Dont FRRRRRREK OUT cutting your long story shortrrrt DON'T BUY It or You arrre used CRRRIB all the time 😂 or be thankful for whats there
Typical RUclips channels: THIS LAMP IS DEADLY!! ??!!!!
Clive: "A potential source of surprises"
My favourite psychopath :)
So, Clive, this lamp is not only germicidal, but also a homicidal and expensive to run. Excellent. How are you going, post-COVID? I hope you are fully recovered. 👍
Given the harsh way it drives the lamp it's also suicidal.
It's Germicidal, its homicidal....aww I thought there was a greased lightning coming there 😄
@@jhonbus
.
Clive got the Chinese chixken flu? No that dudes so tough and smooth talking and great at reining and talking via rolling everything how. Can China gentlentouch germ get him? Lies I say.
Can't transmit any germs if the host is dead. Kinda smart of the lamp tbh.
I've had "Arc Eye". yes, 'sand in eyes' is a great description. Best cure? Several beers, and early night. Next morning, all mostly healed.
Hahaha, yeah done exactly that.
I had that happen exactly once. I had no idea I had injured my eyes until it hit me on the drive home. I had to drive for an hour in absolute misery while not being able to see because my eyes were watering so badly. Mostly resolved by the next morning, though.
You know your going to be miserable when white lights start to turn pink in your vision. I've had arc eye also from welding with a mask that had a corner of the dark glass broken off and gone. I had no idea that I had hurt my eyes until on the drive home from work during the night. The headlights of all the oncoming vehicles started turning pink, then red, then the pain slowly started coming on. It was a miserable night, and part of the next day, before it started getting better.
If it doesn’t make you a little more respectful of the forces you’re working with then life is probably hard.
In ancient times we used these clothes dryer germicidal lamps to erase EPROM memory chips, the kinds with quartz windows. they quickly became unpopular once flash memory came out.
The extra E in EEPROM stands for electrical😉
@@Okurka. I remember all of them over the years
@@Okurka. - Thus the reason their popularity rapidly plummeted after the introduction of the newer, easier to use stuff. That's the sort of time-line one would expect, no?
I coincidentally read a little bit about the history of EEPROM and Flash memory yesterday, because I need to safe some bytes on my Arduino. :}
@@Okurka. ring memory came out way before eeproms
Exactly! Woke up in the middle of the night with sand burning in my eyes and it was "pain level 10"... I'd rather not say how I got into this mess. But your description is SPOT ON. Signed Dum Arse
I've worked with welding at school, before I graduated. I never once got arc flash from welding but I know what it feels like to have dry eyes that feel like they have sand in them.
The case looks like its been designed to hold a "real" power supply with the cooling vents. I guess changing iits use to a fancy LED chandelier might look interesting with the refelctions off the the Aluminium..Whats good for us to see is not really what you want your family buying and getting more than a little tingle from.
It reminded me of the time that i was trying to fix my friend's cheap hi-fi that just died and wouldn't power on after an intense party. I took it apart and started to remove the internal power supply which was a properly built switching power supply, and then i got the worst shock i ever experienced from a smoothing capacitor after the bridge rectifier (so around 325 V DC). The most shocking (pun intended) thing is that the device was sitting unplugged for many hours before i started taking it apart so this suggests absolutely no discharging resistor which was insane. I then shorted it with a screwdriver and it made quite the bang. From now on I'll always check and discharge any capacitors that possibly can be at high voltage levels.
That sounds like a power supply failure too, as it would usually discharge the capacitor.
I once repaired a friend's CRT tv that would not turn on after the power off. The owner told it would be ok the next day. So I powered it up and turned it off. Sure enough, it was dead after that. The power supply was a printed board by itself, so I carelessly had it removed but got nasty shock from the big capacitor. Immediately, I realised what caused the problem. The resistor that connected across the capacitor had gone very high value that unable to discharge the voltage. Replacing that resistor solved the problem.
Same here but with a microwave capacitor that had not been charged for a few hours
I always assume that capacitors in a PSU will be charged up. I keep a 1 k ohm resistor which I apply across big electrolytics (via insulated tweezers). For similar reasons (though safety of sensitive components rather than my body) I always press and hold in the power button of a PC power supply after unplugging it from the mains, to let the capacitors discharge through the case and CPU fans) - I do that before, for example, unplugging a hard disk drive.
Early in the pandemic some of the "experts" were coming up with the "new" idea of using UV-C to clean the air. To which one doctor who went into field clinics for the WHO said, "yeah, we use those all the time". But most amusing was looking at the history of use, it turns out that in the 1930s, UV-C was used to prove that viruses could be airborne, and thus great advances for measles mitigation. But also that UV-C was effective against airborne viruses.
And oh man, the craze of those stupid wands. If it were powerful enough to work, it wouldn’t be safe to use. But, enjoy your blue LED stick...
@@nickwallette6201 There was some research into a specific section of the spectrum that our skin would tolerate well enough and doesn't result in ozone production. Sticking to mostly that wavelength seemed to inactivate many virus particles in the air but good luck getting the quality control right on that with unknown replacement supply chains inevitably messing it up somewhere.
I don't remember if it was eye safe or not, the skin can take quite a bit but uh eyes are probably a little bit more sensitive. Would give you the link but I trashed all those bookmarks a while ago when paywalls started going up again, there was a nice period where many publishers would make the covid related articles freely accessable and that went away at some point last year. And it's been too long ago to remember the specifics like what the title was, which wavelength and publisher.
@@extrastuff9463 Huh. I'll look it up. 👍
@@nickwallette6201 Seems like my reply didn't show up (yet?). I did link to the website of a podcast so maybe it's being witheld for manual approval or automatically removed.
I eventually remembered that it was brought up in episode 666 of "this week in virology". Throwing "twiv 666" into your search engine of choice should get you to the episode notes that contains a link to both articles and a timestamp when they discuss it.
Alternately if you directly want the articles you could search for their titles:
first one, "Far-UVC light: A new tool to control the spread of airborne-mediated microbial diseases"
second one, "Far-UVC light (222 nm) efficiently and safely inactivates airborne human coronaviruses"
The first article is a pre-pandemic one focused on various things, the second one being newer and more coronavirus focused.
@@nickwallette6201 The wands with the mercury vapor vacuum tubes in them are powerful enough to kill the virus at close distances. But, I DO have to laugh at the wands with 8 or so LEDs in them... One being a low power UVC LED, and the rest just plain blue LEDs. 😆
In addition to the potential stress on the lamp of that "minimalist approach" (which may or may not be an issue, I'm not sure), one of the other big issues with that design is that the electrical spikes it generates aren't only felt by the bulb: This design would be extremely electrically noisy, sending spikes back down the power transmission line to anything else connected to the same circuit, and producing a lot of EM interference for surrounding equipment as well. This could cause lots of problems for any more sensitive electronics you happen to have plugged in nearby, such as random glitches or crashes for digital devices, or audible hums in audio outputs, etc (or for things like some sorts of wireless communications in the area).
The glasses you wear Clive are probably protection enough against UVC. It's not like a welding arc. Still good on you for exercising caution.
@@Okurka. Probably with poly-carbonate lenses. Those are pretty opaque to UV light in general.
That's possibly the lowest power factor I've ever seen.
Holy crap that snap was like a fuse blowing. Thankfully you did answer my question though about adding a discharge resistor. Just seems the manufacturer was too cheap for such extravagant things like safety.
He explained recently, that sometimes people send their designs off to be built in China and they figure out how to build the same thing cheaper, often by using less parts, and supply them like that.
I wonder if the UVC will break down that plastic ring in the otherwise all-aluminum chunk. That seems like a weird design decision. Though, taken in the context of the rest of the lamp, I guess it's on-brand. 🤷♂️👍️
I was wondering the very same thing.
In today's episode of "Things from China that can hurt you in unexpected ways" ... what an opening line. Love it ❤😂
The fact that most things come from China sort of escapes our mind at times. Republicans like to drum up war to distract us from an orange cult taking office
Yes, they're seen in the USA with far different (presumably safer) driving circuitry, usually potted in silicone.
I can see why you might expect the envelope to go black from sputtering of the filament but that wouldn't affect UV emission from the flat front face of the tube, which in the examples I've seen is where the UV is shone into the space to be sterilized. Nor would there be much blackening as the coating is partly intended to reduce sputtering, and the filament doesn't stay hot except for a brief time when starting.
None of that diminishes my "oh shit" reaction when seeing that... "circuitry".
Well, that's a fine bit of DeathTech. And made with nothing but the highest of manufacturing and engineering standards, naturally. Fun for all, young and old!
Your voice is absolutely splendid, sir.
Germicidal x-mas lights haha! I have nosy neighbors and thought on occasion about an (UV) decoration light. Look! Pretty bleu light! Watching your uv and ozone adventures puts bad thoughts in my head.
Say Clive, you may want to check your schematic ...
The lamp physically has the capacitor connected between neutral and the hot side of the bulb socket.
You drew it like someone thinking might draw it, not the way, either ignorantly or maliciously, a Chinese engineer had it built.
10:18 "Here you see the UV light is produced by one of the crocodiles from Pitfall."
It turns into a portable HV flyback capacitor after live use, what a wonderfully great and safe invention!
The little disappointed "oh" at 8:37 when the wire came off the circuitry was so funny to me omg
"...and that includes pets and children."
F*** thought I was onto something...
Curious what the current waveforms look like for this thing. I wonder if there's a current spike when the arc strikes on each half of the sine wave.
Spiky and very low power factor.
This reminds me of my past time servicing microwave excited mercury vapor UV lamps for the semiconductor industry. The microwave energy itself was not "energetic" enough to elicit the UV producing reaction from the lamp; an exciter lamp very similar to the one in this video, was employed to provide the photons needed to get the lamp to light. They were horrible, with visible bubbles in the envelope, but were magnetically ballasted. They failed frequently which I blamed on the bubbles in the quartz envelope. The main lamp was a quartz bulb, rotated in a constant blast of compressed air for cooling. They would fail spectacularly, with a loud explosion ruining the reflector from impacts of quartz fragments at high velocity. Where did the mercury go? Into the atmosphere, I'm afraid. Somebody likely touched the bulb without gloves again. Not me.
Those sound similar to the microwave excited sulfur lamps and the tiny tic-tac lamps with RF excitation used in some experimental entertainment industry lights.
I can imagine the "warning" on this thing would be something like;
"Kindly use the upmost caution when operating the lamp. For it creates a massive dose of the Ultraviolet A B and C. Use of gloves to handle lamp. Use isolated screwdriver to ensure proper discharge when upon servicing."
Nah the warning would be.
Watch the hand ✋ danmgerous. hahahah
@@Steve211Ucdhihifvshi Or "smell your hand after use of lamp; smells like pork. Lamp cooks human skin."😅
If you do the math, the capacitor works in a constant current generator configuration.
The resistive variation of tungsten, from ambient temperature to reddish glow, is 1:10. Therefore, the voltage across the filament become ten times higher, and that is when the barium oxide coating close the circuit and emits UV light.
I did the I / V curve with a Variac, an ampermeter and a voltmeter.
The lamp needs desperately a 1 Amp fuse in series with the capacitor, and a 2.2 MOhm resistor in parallel with it.
Thank you for all your efforts !
Highly appreciated...
At the start of the pandemic I considered getting one of these to help sterilize my bedroom while I was out of it during the day, but I realized 1 there are sooo99 many spaces the light would never reach, and 2 I didn't want an ozone buildup in the place I sleep, but 3rd I looked into these cheap lamps too and realized they were capacitored cheaply and just knew one of us would hit lit up like Thor after a few beers, and that was the end of the thought.
Well I am an old fart now but I have been following you for several years. I have to say I find some of my best ideas while learning from your videos. My daughter needs to use one of those breathing masks at night while she sleeps. It has always been quite a chore to keep it all clean. She watched some of those commercials on buying a cleaning machine for them and one day asked me if I could figure out a cheap way to build such a device. I thought back to one of your videos on this UVC bulb so I went online and purchased the clear U shaped bulb. I took a regular glass type light mount and screwed it onto the lid of a plastic bucket. The bucket once held kitty litter so the top was half mounted all the time to the bucket. I screwed onto the side that was always inside. I interrupted the cord going from the plug to the socket with a 110 volt rated toggle switch. Now when she gets up, the mask and hose go into the bucket. The lid is closed and she turns on the switch. That wonderful smell of ozone comes from the bucket and about an hour later the mask and hose come out smelling ever so fresh and clean Sure the stuff is washed once or twice a week but not daily as she used to have to clean the product.
Be careful. The UVC can QUICKLY destroy some plastics.
30,000 times safer than an ethylene oxide kind o' cleaner! Cool beans, glad the UV-C bulb worked like, even better than UV-C LED corncob lamps.
That is a rather clever way of designing a gas discharge bulb, I like it. Would have been nice if there were more kinds, like CFL or neon or something.
Well now Clive, yet another top notch expose. I never tire of your coverage of these Uv gimmickyzeugies. And what is a most rewarding bonus, are the most fascinating people and comments that your page attracts. Cheers!
Thank you for your most informative videos.
We use an 125w mercury vapor lamp then break the outer glass. It provides quite a bit of UVC and ozone.
Dear Clive. We love you. We love how you look to the world. We love the way of your observation of the world. We hug you!
What about the content? 🤔
I've never really paid attention to the wiring on E27 holders or almost any lamp socket for that matter, of course I tend to put the neutral wire on the screw part but since most floor lamps and things like that have a standard (european) plug that fits both ways into the socket so either one could be live and the thread seems to be recessed enough so that you have to be pretty deliberate if you want to touch the thread while screwing it in
Of course in this case it's a bit different since the wiring flips between the holders
I recall having a desktop plugged into a non grounded plug at my parents house (which I know you shouldn't do) and I used to get tingles from the metal case which wasn't grounded due to not having a ground and flipping the plug the other way solved it, I'm guessing it's just a bit of leakage current flowing through me? I also got a buzz from the aluminum bits on my keyboard
I'm pretty sure that the instructions for those floor lamps (at least those with proper documentation and a legit CE declaration that actually holds its promise) say that you are required to unplug them before changing a bulb. (In practice, almost nobody does that, I know.) That's just one of the disadvantages of non-polarized plugs.
Leakage current through a capacitor in the switching power supply.
I really like your sense of humor! please keep do such a good work.
"This lamp can hurt you in two ways."
Knowing some of the devices featured on this channel, I'm thinking UVC plus shock risk. Now to watch and find out!
Wow, it's even worse than I imagined. No resistor across the capacitor, saving maybe $0.02 per unit.
They were probably saving more with the labour. It's a bit tricky to put a resistor across this huge axial cap. The resistor's own leads are probably not long enough, they should have extended it, and put heat shrink on it. Or they just could have ordered custom 1M resistors with extra long leads, but the heat shrink would still be needed to prevent a short with the E27 thread.
They chose the simplest "solution" instead: "F it, it works without that resistor!"
I purchased some of these a couple of years ago and used a 4mf power factor correction capacitor salvaged from a 20 watt flourescent lamp fitting. These are intended for direct connection across the mains.
And now for another episode of Big Clive's "Fun with Chinese consumer grade torture devices"
I figured out a third way, I won't tell you though... for safety, y'know?
Oh my... So once upon a time I worked at a science center as an exhibition tech (best job ever) and some high voltage with a wimshurst generator and a cf bulb.. it lit up neatly via the wireless transmission of power. I did not know the circuit inside was not diode protected... I'd have peed my pants and dropped the bulb if I could when I was bit thru the bulb threads....
"spicy!" I love your videos man.
One of those metal halide store lights gave me a nasty surprise you're talking about, here. I guess there was no discharge resistor across the capacitor that was inside. But it was, indeed, meant to be "permanently" connected, not with a plug, like the way I was using it. Still, should probably have some kind of safety discharge resistor.
Thanks for posting!
Not safe either: it would give the electrician a jolt!
I bought one of those big UVC bulbs you previously showed. It works great, loads of ozone and kills mould.
i have the same light, only look at it through clear acrylic for safety, but they dont seem to work, did the banana test for 10 min no change on skin color, while doing the same with philips TUV PL-L 36W makes drastic change in only 5 min
To be fair, this one is just 3W.
when i see "this lamp can hurt you in two ways" that just makes me want it more
I looked into uvc lamp once for maybe 10 seconds.
i could feel it in my eyes the morning after already!
I have never seen incandescent type UV lamps until today. I always thought that those came only in the fluorescent tube type.
I watched the video without eye protection twice, because of the pretty blue light! now my eyes are burning;)
Interesting as always, but got me thinking...
Many reptiles get cataracts and issues from lighting. Halogens seem to generate very different amounts of UVA, UVB and probably UVC. Maybe one day you can measure actual outputs to give us an idea what we might be doing to our little captives. Of course different reptiles need different lighting and are sensitive to different lighting... Lush jungle vs desert vs cave.
I remove glass lens to get UVB, but after your excellent video I fear there could be UVC. My Crocodile Gecko actually doesn't need UVB, so I switched out to LEDs.
Cheers 🍻
Crocodile Gecko 🦎
We had a pressure washer that basically did the same thing when I unplugged it if I wasn’t concentrating when I wrap up the power cable I used to get a nice hand flinching tingle off the pins on the plug.
These lamps will give you and your pets cataracts over time. Your pets will get them much faster.
I used to have a 120 volt AC fixture that provided a combination of UV and IR simultaneously, centered around a mercury vapor discharge. [That combination is good for causing human skin to produce vitamin D.] Inside the open-faced unit there was a large-ish glass tube (about 1 inch diameter by 5 inches long) with filaments inside at each end, plus a few drops of mercury visible inside, and coiled resistive wire (nichrome) wound onto ceramic supports at each end of the glow tube. An open cage of welded wires across the face prevented easy access to the dangerous bits. When power was first applied and the external heaters were cold, more power went into the internal heaters, getting them hot enough to strike an arc at low current in the rarefied mercury vapor at room temperature. As the tube warmed up, more mercury vapor was evolved from the drops of mercury, and current increased. Color of the glowing vapor also shifted. Gradually the current would rise until the external heaters got enough current to glow reddish-orange, which also meant the tube had minimal voltage across it then. Unfortunately I did not measure the changing or static voltages or the overall current, but I can say the entire fixture was both old and of low mass, so it did not have any magnetic or solid-state ballast inside. Instead it used resistive ballasting, via the external heater coils. As a result, it presumably had decent power factor, since much of the load was resistive. Again, not measured by me.
3:00 if I experienced a shock like that that lamp would get promptly crushed and thrown out. That would sting. Wow.
4:34 lol, "you might get blisters if you hold it close to your skin"... actually has a blister or something there XD
Wouldn't that be problematic in other ways too? Big cap able to put voltage on the line for anything else that may be sharing the same power circuit? Was expecting something more like a ballast circuit inside the lamp.
i bought a 25watt UV-C bulb (ozone edition) last year and used an adapter to fit it in the bedrooms central light socket. the mold in the air was quite bad.
Running the bulb made the whole room stink. Ran it for the suggested 15 minutes then vented the room for an hour it smelt worse than a swimming pool full of chlorine but the mold an toxins had completely gone, could once again breath properly the filament in mine is completely different it has a coil of thick metal wire inside the bulb like an induction heater but produces a lovely blue tint like yours did. £40 well spent id say
5:27 "Germicidal Christmas lights are a great idea"
This is my new favorite channel "Potential source of surprises". And I'm only a few seconds in.
I had a hoover once that if you grabbed the mains plug after unplugging, it would give you a jolt,i think it must of been a suppressor cap in the hoover input circuit.
That really sucks 😃
@@MrTheHillfolk LOL,that's what my so called best mate said about my girlfriend.
That capacitor inside is used as a tension divider and also prevents DC bias. The capacitor is Polyester film capacitor type and It is most commonly used in household products. The build charge on the device is not a problem and can not harm if permanently wired on the power grid. The problem occurs If the device is plug wired and portable, indeed. On the other hand I prefer UV light bulb over chemical deterrents for killing germs.
“Don’t touch this it will give you a nasty shock”
So he grabs it to see if discharged 🤣
It's slightly more tolerable and controllable if you're expecting it.
Capacitors are fun.
I worked security for a while, some got handsy to plea, other got angry.
'Sorry, I cannot break the rules.'
I decided to make two silver stripes, attached to a 300v capacitor, that ran down my sleeve.
Had a nice charge button off a 9v in my pocket, in the case someone was extra annoying, or to catch someone off guard.
No one would even feel 9 volts.
@@davelowets
Ya missed the part where it charged up a 300v cap.
I had a multiplier circuit that made the strips not friendly to the touch.
300v is still not very much, but it's enough to divert attention long enough for me to react to hostility.
_And it was fun to have people test it._
An English welder might get arc eye .but a Scottish welder gets och eye
Superb
After finding a need for a new bedside lamp, I noticed quite a few very pretty ones that have USB outputs on the base and touch response for very low prices. I wouldn’t be surprised if a variation on the cheap pink charger guts were just wedged in there as £19 for all this seems near impossible. Maybe there’s some opportunity for you there Clive.
They didn't even bother with a bleed resistor.
China number one!
"Germicidal Christmas lights!"
Taking a charge from a big cap is something. I had a motor cap zap me once and for me it was much more painful than residential AC mains. Granted mains is more dangerous due to the AC characteristics, it still hurt like hell.
The most painful one of that kind I had was from the capacitor that drives the flash on a compact camera. Only did that once!
@@revbobuk as a kid I used to go to the local photography store and asked for discarded disposable cameras with flashes. Then I took it apart, soldered wires to the capacitor and superglued a piece of bicycle inner tube to my hand and had contacts on that and hid the wires inside my sleeve.
I also added a switch there so I could easily control for how long I'd charge the capacitor. Usually only went for few seconds and it was still a pretty good zap when I went to my friends and shook hands. When overdoing the charging it actually hurts all the way to the shoulder for quite some time and burns the skin :)
A shock from DC is more dangerous than from AC at the same voltage, isn't it?
In my younger years,i have experienced ark eye ! i wouldn't wish that on anyone ! i was glued to someone welding and was enjoying the blue light (albeit to close) no problem until 1 am and it is as Clive puts it,it is like someone pouring sand into your open eyes ! ever since then i can't even watch someone welding on TV and i look away ! be warned !
OOF is what i said hearing the screwdriver pop. wow
"things from China that can hurt you in unexpected ways" - so, basically, my parents and their high expectations?
Nice shocking hazard you got there! BTW I have a capacitor which is 13000uf at 500volts, surely if you would touch that when fully charged you would get a chock big enough to make you glow like that UV bulb lol
That could be a defibrillator grade shock.
@@bigclivedotcom probably worse that that lol
lol that's 1625 joules. Even most defibrillators only go up to 250 joules. Definitely not good for the heart
@@elietheprof5678 indeed, I actually blew two 240volt light bulbs when load testing the power supply I built where that capacitor is used in and it can actually just by that charge supply over 100 watts of power for way above 10 seconds. Not even Electroboom would play with such cap. The “Ripple current” rating is over 20 amps on it and I dare not even think of the short circuit current ha ha. I love that cap
Three ways technically if you chuck it at someone's head
I wonder what the shock would be like compared to a fully charged camera flash capacitor? That was pretty bad!
Wikipedia says those are about 80-160 microfarads, compared to the 4 microfarad here. Not sure how comparable those numbers are.
@@trevorc4413 would be better fitting here to compare by joules. a typical camera flash has around 5.4J (@120uF & 300V). Those 4 uF are equal to 0.22J @ 330V. But also many other factors matter like the internal resistance of the capacitor (and thus maximum discharge time -> maximum current). A defibrilator for example is charged to 150-360J. So no serious damages from camera flashes, just pain. Also got shocked by one a couple of times. those "single use" cameras a great for building mini coilguns
@@KekTekDe The cap I got shocked from was about the size of an AAA battery and the pain went up my arm to about my chest.
@@Xenon777_ yeah these shocks can be pretty nasty. wouldnt do it on a daily basis lol. always be careful around higher voltages (>50V AC, 100V DC). When working with those voltages, make sure to be extra careful. principles like "one hand behind your back" for example (so you cant possibly close the circuit through your whole torso).
I am quite shocked (intended) at the voltage discharge across the plug pins. What a flash and crack as the point of the screwdriver head touched the Live pin... Nasty indeed. I'll have to remember if I must handle one of these UVC emitters to short-out the plug pins just in case I get ZAPPED.
Does the glass have a slight violet tint to it or is it an illusion?
Just clear.
Germicidal Christmas lights ..pine scented ozone..excellent work as always 👍🥸
Wouldn't that capacitor be extremely hot after a few minutes as it's being loading with so much current 50 times a second and just bust it's electrolytic nut prematurely and in turn shortening it's service life?
The capacitor is only holding voltage; the lamp itself is very very low power. Plus you may be thinking of a resistor in series with a high-current circuit, it indeed might get hot.
It's not an electrolytic, the dielectric is like Mylar. That is a low loss dielectric and will not heat up.
@@georgegonzalez2476 ok cool. Thank you for that. I'm still learning so I appreciate being corrected so I can learn about the stuff I don't know, which is a lot haha
@@mystica-subs cool. Thank you.
When covid struck, I bought a whole bunch of them bulbs. Nobody could tell me how simple to put just a large capacitor in series so they all died once I had bound matching sockets. Erasing EEproms was also on my mind but the applications have become rare.
So beginning to think Clive is a bit of a sadist...in a nice way.
"Germicidal Christmas lights, a great idea."
You must be new! Welcome! The coffee is over there.
"Point away from face."
"My face, or theirs?"
I often get quite a shock off the end of OnePlus dash/warp phone chargers, I assume they have a capacitor in them that's not discharging much like this lamp.
It's weird as you'd expect better from a proper manufacturer.
Just proves that they are not a proper manufacturer.
That is one worthy of a teardown, I would worry the transformer is sketchy too if it's too cheap to have a discharge resistor.
"I'm going to unplug that before I get nasty experiences." You have a way with words, Clive.
The fact that they come from BangGood is quite appropriate.
00:25 - ".... a potential source of surprises..." - nice one Big C - I'll be using that one to describe any dodgy stuff in future. Thanks Bro.
So, It's should be called ultraviolent lamp
Feel like this could be another ‘cooking with Clive’ moment, with bowl and a piece of bacon inside with the lamp on top?
In North America we use 120 VAC/60Hz. Both the voltage and line frequency difference would make the difference for the capacitor. I believe the Xc at 50 Hz for the 4.2 uF cap is equivalent to approx 770 Ohms. Looks like the manufacture of that lamp was too cheap to add a 1/2 Watt 1 Meg Ohm resistor across the cap to discharge it. I would use a 470 K resistor to discharge it faster.
One upon a time I picked up a very expensive HP RF Vector Voltmeter. I grabbed the mains plug to save it from dragging on the ground and got a decent shock from the plug and nearly dropped the instrument. Wouldn't have been a good look so early on in my career.
As for this lamp it seems very similar in its design to the self ballasted mercury vapor lamp except the envelope is quartz glass with no phosphor.
I knew it was going to make a sound when you bridged those contacts, it still surprised me.
I remember a Zenith TV that used to hold the capacitive charge when unplugged. The bleeder resistors in the switchmode power supply must have failed in that particular TV. Nasty surprise, indeed.
One dangerous lamp 🔆
Clive, could you consider a video on what all the numbers on the hopi mean? Well... I suppose mainly the power factor.
Is it just a measure of electrical "wastage", so hitting as close to 1 is good? Similar to how PC power supplies have the 80+ bronze/silver/gold/platinum scores?
Hi, electrical engineering student here! I'll see if I can help explain.
In short, Power Factor is a measure of how far out-of-phase the voltage and current sine waves are, with values closer to 1 being more in-phase (and thus "wasting" less power).
At the cost of some hand-waving, we can consider inductors and capacitors to be "resistors" in the imaginary plane. This means that resistors consume "real" power and capacitors (and inductors) consume "imaginary" power.
If we graph the power consumed, both real and imaginary, on the complex plane, we can find the hypotenuse of the triangle formed. This is called "Apparent Power", and always has both a length AND an angle (because it's a vector)!
But writing "800kVA angle 35°" is a pain, so we shorten it with power factors. The power factor is just the cosine of the angle of the apparent power -- in other words, the ratio of the magnitude of the apparent power to the magnitude of the real power.
But that's not quite enough, since cosine is an even function (plugging in -45° and +45° has the same result). Thus, we need to add the word "lagging" or "leading". Leading means that the circuit is more capacitive, and the voltage "leads" the current. Lagging means that the circuit is more inductive, and the voltage "lags" the current.
Since this particular death trap is almost JUST a capacitor, it's almost all imaginary power -- which leads to the very, very low leading power factor.
Does anyone else other than me remember the combined infrared and ultraviolet lamps that used to be around in the possibly 70's? I'm willing to bet as much UV C came off as A & B. It was like looking into the sun (I was only a kid & knew no better)
My dad used to spend ages sat in front of it, back to it as I remember.
My parents had such a device and it somehow always creeped me out. I only used the infrared part of it when I had a cold. (Ours allowed to select UV + IR or IR only)
I remember my mother having one. The smell alone told my young self it was dangerous. When I got older i realised it was chirning out dangerous levels of UV and a fair whack of ozone. It had a weirs bulb in the centre for the UV and 2 'bars' for IR i think all in a metal case that folded shut.