Dim bulb testers are still used in guitar amplifier repair, at least for the ones that are still tube- and transformer-based. (Edit: changed brain-o "amplifier-based" to "transformer-based".)
Probably ought to mention that it only works in that fashion if incandescent bulbs are used. LED's will not offer the same protection that the resistance of an incandescent bulb does. Clive may have mentioned this and I missed it... Either way, its worth saying twice.
I looked up the ratings for glass fuses and was surprised that a lot of brand-name manufacturers rate their glass fuses to break 10kA on 125vac, but just 35A on 250vac. It seems absurd, but it explains why glass fuses are the norm in the US.
It’s no joke. Here in Canada I remember testing a Japanese 5A 5x20mm fuse on an industrial (just in an industrial rental unit) 240V circuit- the fuse exploded very loudly scattering shards of glass- it must have arced from the end caps. Evaporated metal on the glass shards. The extra length on the old 1.25” fuses probably helps. Bulb is better than heater of course because it is nonlinear- used that when developing a VFD- saved a handful of them expensive semiconductors every time it lit.
Yeah I’ve noticed that too. I think it all comes down to having the voltage to sustain an arc. 120V can arc, in fact welding torches output less than that, but it can’t maintain that arc across the 20mm length of the fuses.
@@gloomyblackfur399 yes, but sustained arcing at below 150vac(rms) is very low chance. unless it's a gas filled chamber meant to do so or super high humidity and open air( for replenishment of the oxygen rich air with humidity for increased conductivity. glass fuses are used in minimal current draw devices now days and in smaller devices, or holders which will not burn easily.
Back in the 1950's US (and still today in some old buildings) you could screw a light bulb into the fuse box. This was a great trick to hunt down short circuits without wasting fuses.
@@davidg428830A fuses screw in to 20A but don't make contact because it has a more shallow tapered center. 20A fuses will work in a 30A socket. They have a steeper taper to reach into a 20A socket.
They don't blow at their rated voltage, only good for current limiting, and passing current. Could work if using a 12v bulb for example, but you still run the risk of passing current through an arc flash when it burns out or explodes.
Yes.....Two 100 watt 240 volt tungsten filament bulbs wired in series are useful in testing for incoming 440 volts or 240 volts by how Bright or Dim the bulbs light up .
@@kelimikethat’s the idea. If there’s a short circuit, it just lights the bulb and still limits current to less than an amp, instead of blowing up your circuit with a few hundred amps of fault current and then blowing a fuse. To be clear, this whole setup would be plugged into a receptacle that is itself protected by a circuit breaker.
@@deltab9768 The idea was stand in as a fuse, and then completely fail as a fuse? A fuse is supposed to open on a short circuit fault. A lighted series bulb is not a way to do this. It is a way to test for short circuits, not protect from them. This is only a great tip for someone who uses fuses to test for faults. They would go through fuses quick, so in this case, yes, use bulbs to test faults, not fuses.
@@kelimike I don’t think anyone is suggesting that this is a 1:1 replacement for fuses. Yeah he said “surrogate fuse” but this is clearly an additional current limiter, for a situation where you think there is increased risk of a fault, but you can’t test it with a meter because there’s voltage and frequency dependent components like transformers. In the event of a fault it will limit current to a less destructive value and (depending on wattage) will prevent damage to the equipment that a fuse would not prevent. At a certain point you’re arguing against his choice of two words, not against the concept that’s pretty easily understood.
I built something similar myself, just 2 lampholders in series so i can put a led lamp i have repaired or modified in series with a 60w filament lamp in case it all goes wrong.
I think whomever named this product got the concept wrong, it is not explosion proof, it might be short-circuit proof, as I see a lot of other comments called it a dim-bulb tester... like Mr. Carlson's Lab when he is repairing old radios and such and doesn't know if it will short out. I hear Explosion proof and I think of "intrinsically safe" I once wired an control panel that needed everything in it rated as such, that was my first time ever dealing with this concept and I learned a lot. We used relays with contacts that are rated for use in explosion environments... You can bet these aren't cheap. Quote: "The standard ensures that an "intrinsically safe device" is incapable of triggering combustion or igniting any gasses or fuels. To put it simply, you can use it around gasses or fuels without risking static electricity or heat discharge from the device igniting the surrounding volatile gasses, powders and liquids."
@@marcogenovesi8570 Yes, exactly... that is what I believe happened too. I've seen a lot of funny examples... some cannot be said in "polite" company. LOL
The first time I encountered the phrase was in a factory building that worked with flammable solvents, it had "Explosion Proof" light switches. Big black cast iron things with a knob that went "CLUNK", like something salvaged from a WWII submarine. I remember thinking, if the factory ever blows up, these switches will probably be the only thing left intact.
@@marcogenovesi8570 That does indeed produce some outrageous results! Of course, when you have items such as hand grenades traditionally being called "divine bone dissolving fire oil thunder crash bombs", you may run into some issues.
Oh it’s a lamp limiter. I assume you have watched the various valve radio repair channels including the ones I spaffed off several times. Still not many tools that can do what a lamp limiter does, an amazing bit of bench hardware for people like me that repair mains equipment
I use an AC labsupply, but before that I used lamp limiters combined with a reset-able adjustable fuse (DIY build) You need a big lamp because otherwise the voltage-drop is to big for many smps (and that is what I find in 99% of what I get on the bench)
The first time I read your post I thought 'well, that person really, really likes valve radio repairs'... Then I realised my brain had inserted a rogue "to" near the end of your second sentence.
When I took Radio Shop in High School in the 1960s we would build and test small tube radio receivers. There was a special test bench we had to use- there was no power at our work stations other than for our soldering irons. The test bench had an antenna connection and a speaker we would connect our receivers to. The power socket had a twenty watt bulb in a ceramic socket screwed to the bench in series with it. The teacher explained what it was for on the first day, and warned us that any student who plugged their radio into any other socket in the shop would be immediately failed. Nobody tried him on it despite typical teenager stupidity.
Connecting a high watt bulb (like a headlight bulb) in the place of a fuse is an old automotive electricians trick for locating short circuit witout wasting fuses. Just disconnect things one by one from the circuit until the bulb goes dim and the rest of the circuit starts working and you have found the short. Very handy in circuits where there are a lot of consumers like the marker/side lights on a truck or a trailer.
The irony is, this inline lamp box is probably a lot safer than some of the dubious "test setups" I've seen over the years of people running a bulb in series with old tube based TVs & radios (current-limiting to not make old waxed paper capacitors turn into little flame generators), though even this one still has its' safety issues, but, it's expected from the country of origin it seems.... :P
@@LawpickingLocksmithno one died in my 1980s household with those 'death traps'. Metal lamps, not grounded, non polarized and no one would unplug them when changing the bulb 💡
It depends on luck but even some dim bulb test lamps have too high wattage to prevent transformer damage due to shorted HV load - especially on smaller equipment that has very few tubes. For foolproof mains-powered testing you need an AC bench supply - voltage- and current-regulated. You get one by attaching a step up transformer to an audio amp fed with a 50Hz or 60Hz tone. The current limiter further limits the amplitude of the incoming tone. The amplitude modulator doesn’t need to be linear since it’s in a closed feedback loop. So a resistive divider on amp input, with an LDR on the grounded leg, is all it takes. When the output current is past a threshold the usual op-amp starts driving a LED that reduces the tone amplitude via the LDR. Super simple and effective.
Hi Clive, another informative video. It is always to interesting to see what is inside of piece of Chinese test equipment! With that non-polarised plug there is a 50% chance of the exposed base of the bulb being live! Nice!
@@DavidVR2More correctly, the live wire will sinusoidally alternate 50 times per second, between+320v and -320v with respect to the neutral wire, which should always be at 0v. It's 320v, not 230v, because 230v is only the RMS value.
hey BC, me again. i did a thing today which has eluded me for months. despite doing things far more complicated, a year ago i saw your ancient instructions from the BC site from the tiny bandwidth days for the joule thief and it never worked. i always put it down to being ham fisted, and being crap at winding inductors. but today i thought i'd get to the bottom of it. as soon as i thought about it it was immediately apparent i had in the past taken no pains over the winding polarity. 1 minute with voltage supply, a meter, and a sharpie and it was all good. i am still smiling from lighting a white led with a mere .7v.. it was lovely. seeing how much more readily it turned off rather than on. and the way the duty cycle + changed increased with increased voltage. brilliant. i have had a whole day of fun.
Speaking of light bulbs, we made a board to test e-bike batteries. This has 4 car headlamp sockets on a wooden board and a terminal strip. It can be wired for 24V, 36V or 48V batteries. Each bulb is about 50W so the total is about 200W. A good battery should last about 1 hour. When it is on full power it looks like an EZ Bake oven.
A factory-made dim bulb tester. If only the connectors were rated for mains voltage (being speaker terminals, they are not) and a socket outlet was available... I've got a pretty advanced test setup in my lab. On top of three switchable dim bulbs of different power, it has a separation transformer and a variac, both with true bypass relays... and a voltmeter and an ammeter in line with the circuit. Arguably more advanced and better made than Paul Carlson's! That's Keritech level of over-engineering :)
I got curious as to what the rating of "speaker terminals" was, so I had a look on some suppliers and I found a pair on farnell than claimed a 1000 VAC rating! Stock code is 2911029
Your comment about glass fuses is a revelation to me. Almost every piece of consumer electronics I've ever opened has a glass fuse directly on the mains input. It's rare to find a ceramic fuse.
Back in the 90's working at a consumer electronics repair shop, we had a similar setup for testing equipment so if you were say, working on an high powered amp and just replaced the very pricy amp transistors, but weren't 100% sure why the blew in the first place, it could save you from having replace them again! On a side note from the same era; in the Bose Acoustimass subwoofers that were very popular at the time, the used several small bulbs inline with the speaker to not only protect it, but also to sort of "round off" any clipping, making it sound similar to it being powered by a tube amp. It was fun to crank them up a see the lights flashing with the beat!
Reminded me of the ballast lamp system we used in telegraph circuits, although the resistance in the bulbs rose as they lit, avoiding the need for a fuse.
With the addition of a polarised plug and some labels this is a neat little dim bulb tester essential in any repair lab. Saves fiddling with sockets and wiring to make one yourself.
0:23 This is a Euro plug, type C. This is used in many countries. If you have a small screwdriver and can overcome the shutter, it will even fit into English sockets.
Two things to consider 1. BS1363 plugs have a fuse for a reason, we use higher current sockets than most places. 2. The pins on a Europlug are sprung inwards and the tips of th pins are bigger than the shaft. Combined with the way the contacts are designed in a typical BS1363 socket this can lead to europlugs getting stuck. If you must do the screwdriver trick then please at least do it on an extension lead rather than a socket that is part of the fixed installation, so you will have the fuse in the extension lead and so that if it gets stuck you can unplug the whole extension lead.
You just demonstrated a "Dim Bulb"Tester" as used by folks restoring old vacuum tube radios to detect if there is a direct short across the line and limit the current to the radio.
as someone who works with explosion proof electrical installs in the fuel industry... i can DEFF say... we might want to get a 2nd opinion on Temu descriptions before assuming accuracy in their claims xD
Back in the early 2000s as a broke teenager i used to use the same principle on my hacked up electric scooter. It didnt have any sort of speed controller, just a large relay that gave the motor full voltage from the battery. Kept burning out motors so used a couple of high beam headlamp bulbs in series with the motor as a poor mans soft start. Then had a second relay to bypass the lamps once you got upto speed. Worked an absolute treat
I learned this trick from a friend who does live music events and I often help him repair amplifiers. I made myself one of these with a single mains outlet, The little speaker terminals look quite handy! I might add them to mine
Another set of clip-ins for the load socket could be used for series current limiting caps. Or use an led bulb to serve as a current limiter for smaller test loads.
I have used the same system for years for repairing amplifiers, a 150watt lamp in series with the supply. It will glow briefly until the power supply caps charge up, but will stay on if the bridge rec or the output transistors are short circuit.
Since I can buy all the parts from AliExpress right now, I have to conclude this is someone's DIY project. With a couple of hundred bucks, a savvy builder can have custom tooling for ABS injection and make their own custom enclosures. They have the entire Shenzhen electronics market to sell to. If you are Chinese in this field in Shenzhen, you're making a killing.
There also the risk that metal vapour from a blown element in a glass fuse can plate the glass leaving a high impedence path from live/phase that might give the impression that power has been disconnected, but which will still give you a nasty "tingle" should you touch it.
@@jamestappin4741yea I think pieces of that cap are going flying if enough current keeps arcing across the fuse. The inner plastic of the fuse holder would evaporate and build up pressure.
I had never thought about a blown fuse getting plated with metal and staying conductive. That’s kinda scary since even if the short circuit is stopped, you can die from less than 1/8 amp of current.
yes. I built a quite similar looking contraption when young: switches to individually turn sockets on and off for computer components. I felt like commanding a space-ship! Until one of the switches got so dirty it shorted out and pulverized the glass-fuse I had used with a huge bang.
Oh a dim bulb tester, a bit much for what it is, believe those should be used with as high a wattage bulb as you can get, and the tungsten ones are harder to get now in the UK or Europe, certainly not in the shops any more 😑 Why not see just how much a speaker terminal can really take? I should think they could do at least 500w relatively easily
They are hard to get here in the US also. You might be able to get some 25 watt appliance bulbs, but I don't think I've even seen a 60 W bulb in years. And forget about 100 Ws.
I had a similar idea on my test panel at the bench when I was an electrical apprentice 40 years ago on the docks. It had a 250w lamp on the live side connected to a test rod which was a brazing rod on a long piece of wire. The vice was grounded and it never failed me. Even had lamps in series for the 3 phase stuff. Wouldn't work now with ELCB's of course.
In the RC hobby, we call it a Short Saver. Essentially an automotive bulb in series with the LiPo battery tests your soldering and components the first time you power it up. LiPos definitely don’t like shorts 🔥
Ha! It's a dim-bulb tester! I had built one of these a good 25 years ago for working with my antique radios and TVs before I had a Variac. The higher the wattage of the bulb used in the test socket, the more current will be allowed to pass through the device under test. Resistors could also be used, but the bulb also gives a visual indication.
This could be for use in stores too. In the Philippines at least, the staff in a store will demonstrate that the product you are buying is in fact working, before you take it home. Be it a TV or a light bulb, they will plug it in and show you. I don't know if it's the same in other countries.
the tube radio people call this "restricted power". the Incandescent bulb with the cross switch for unrestricted power is common in repair shops since the 1930ies. but they used to have proper isolation transformers too, so live/neutral are not referenced any more. (as long as you do not mess up via the ground of the RF connector or the ground of the oscilloscope, iow: you need another transformer for the oscilloscope and a ground free RF transformer too in a decent workshop setup.)
In the valve amplifier repair community this would be called a "dim bulb tester." In general, if the _must be incandescent_ bulb goes dim, at least you don't have a dead short.
Yep, brings me back to electron beam TV service, when we used a 100W bulb with 'gator clips to jump fuse holders to check if we missed a shorted component...
Interesting bit of kit! That 20mm fuse can easily be replaced by an HRC one, and there's enough space there to put in a longer fuse holder, offering better protection. Alternatively go for one of those push button re-settable breakers if you trust the ratings 🙂
I’m using a similar home brew box to test tube radio’s… you never know how far the supply capacitor is gone. Works fine. Mine by the way is a lot safer then the Ali express type you show here.
Some old armature testers also had a built in continuity tester. It was nothing more than two probes connected to the mains with a low wattage light bulb in series. Somewhat scary, especially if someone replaced the bulb with one of a high wattage.
My dad always used a bulb in a holder screwed to his bench to test things. Inspired by your channel I recently knocked up test box, although mine is earthed and has an RCD plug, circuit breaker and a power meter module, output is to a UK socket rather than bulb holders. I did need some quick terminals for hooking up leads and despite searching and searching, I couldn't find anything other than those speaker terminals so used some too. So useful for checking wattage and PF of new lights
I presume you know about the CLIFF Quicktest which Clive often uses. If you want a cheaper solution that's safer than speaker terminals I'd just use some Wago Lever Nuts.
A pre-fabricated dim bulb like this is only good for the general public if they show on top a drawing of the connection lines between elements. If not they could be confusing and dangerous to some.
It's very stylish indeed. They are really into the white theme. White case and white wires accented by the black sockets. I wonder if they make a pink one.
F.A.O. BIG CLIVE :D Have you ever heard of a drag racing Henry hoover? well, on my way home today one of the house locally hat dumped out a yellow hetty hoover, now I love henry hoovers and the company itself, still family owned in the UK, have since I was a kid in the 80's, a true testament to robust modular design and so I know how to fix them up. Have done for folks for a while over the years, anything to stop people buying a bloody Dyson, made of tissue paper by a tax dodger. Anyway it had no wire so I stripped it, good bushes but the motor sounds gruff as buggery when i wired and ran it, had a look at its windings, free wheeled it and it all looks good so I wondered if there was just crap on the bar, I noticed the bushings while still having plenty of life, were distinctly more oily/wet than my henry. So I went into my tools and my other half a wonderful man called Lewis for the last 15 years, yes we like dorathy too, had purchased a new can of contact cleaner for me, not my usual brand and indeed at times I just use WD40 but this was "made by" WD40 so I figured it would do the job and I blasted the hell out of all of it, gave it a bit of a wipe down and popped it back together. Interesting thing about WD40... once you spray it onto a surface, the stuff isn't flammable. Turns out that's not actually the case for their contact cleaner... and well... I was rather liberal with it so when I re-seated the motor back into the top housing and turned it back the right way up the remnants of my spraying must have gathered somewhat internally. I flicked the switch on and for the brief beautiful moment before I was deafened it ran like a dream, followed by a VERY Loud POP and a 3 foot green flame that fired out of the exhaust vent. Ah the fun I get up to at 1 in the morning. try it some time, its hilarious.
Exciting. I'll have to give that a go. There are horror stories of people spraying all the mechanisms in their pinball machine with WD40 (not a good thing to do), and then immediately trying to play it, and setting the solvent on fire.
That's a short tester, it's a useful tool for troubleshooting a device that is AC powered and trips a breaker. I've built and used such tools. This is not a device that could be used in any capacity with an explosive location and meet any code requirements in the US. If you use this as a short tester and don't understand it and how to keep yourself safe it will kill you. If you use this as a safety device in an explosive location you could kill everyone in the building and maybe a few neighbors as well. Thanks for doing these videos and shinning some light on these dangerous products.
Based on some pictures found on aliexpress, the large socket at the end looks like a Westinghouse socket used in the US from the 1880s to the early 1910s.
Didn’t know that about glass fuses! It makes me wonder what other simple things I don’t know… Interestingly some IEC sockets I have purchased before came with glass fuses pre-installed.
Fun fact, China have almost no standard AC plug before 1990, they got Australia like plug, US type plug and also Europe type plug on all kinds of outlet, very confusing, even today they usually buy the power strip (power bar) which accept multiple plug, also means not good, even BT thick square legs is a bit loose, even on fire before my eyes. Back in 20 years ago, I know some Hong Kong invested factory even only use BT type power strip inside for safety, sadly most of them quit China now.
Yeah, power outlets in China are kind of interesting. It is the Australian type with slanted prongs but inverted with earth at the top, along with US flat prong and sometimes Euro round prong. I did happen to visit the British Embassy in Beijing, and I did see they used British BS1363 standard outlets and plugs. Of course that Embassy is UK territory, so they have to comply with UK standards.
I don't know what the Australian type outlet in China is rated to, but I've often seen them scorched and melted around the holes, because they were overloaded. Unlike the UK which prohibits power outlets in bathrooms. Bathrooms in China often have a couple of power outlets. They also have large cylindrical water heaters for the showers etc, might be 2-3kW, plugged into those outlets. Washing machines are often in the bathroom as well.
WOW a new name for a a dim bulb Tester. I have one on my bench. it plugs into my variac. and the piece of equipment I'm working on plugs into my dim bulb tester.
To me "explosion proof" means electrical enclosures, i.e. cabinets, conduits, switches. sensors, and motors, are sealed in such a way that flammable gases or vapors can not get in to cause an explosion if an electrical spark happens inside. That tester looks more to be a "spark proof" test box.
I recently built a (very) poor-man's current limiter by splicing one extension cord into series with another then just plugging it into a desk lamp with incandescent bulb in it. I can easily add more lamps to help adjust the wattage.
Yep ! ( Thanks , previous comments ) .. the " dim bulb " tester is the MOST USEFUL bit of electrical kit .. not only will it stop you blowing fuses .. but .. you can test [ unmarked ! ] transformers with safety ( for YOU ! .. and .. the transformer ( ? ) .. just use a ( low wattage tungsten bulb ) for tiny ( 1 inch transformers ).... tried - n - tested ............... DAVE™🛑
The "tungsten filament bulb in series with the supply" method is also sometimes used when powering up old valve radios. The filament naturally has a positive temperature coefficient of resistance; which means the hotter it gets, the less current flows through it. This gives it some self-regulating effect against voltage variation. It also acts as a crude milliammeter; and with a correctly-functioning set, you can see a bright burst corresponding to the inrush of the valve heaters which then dims as they begin to warm up and the resistance increases, until the rectifier valve begins to conduct and the light bulb gets brighter again -- perhaps dimming slightly once the smoothing capacitors are charged. If there is a fault anywhere causing the set to try to draw too much current (such as the DC-blocking capacitor connected to the grid of the output valve having died of old age, causing the valve to turn on hard and pass excessive current through the speaker transformer), the bulb will light brightly, but the radio can never get more current than enough to light it fully, which serves to limit the energy available to do any damage (energy which, in the worst case, will be distributed to each piece of shrapnel as 0.5 * m * v ** 2). It's just a shame tungsten filament lamps are so hard to get nowadays, because idiots kept insisting to try and use them for general illumination .....
A useful piece of gear, assuming you know what you are doing. Though, I do worry about people who don't know what they are doing buying things like this who may end up injured or worse.
A bit ironic that a "safety" device is so unsafe :D. You can make a dim bulb current limiter for dirt cheap and be safer than this thing. Even just an old bulb and a socket/cord can do the trick.
The high mortality rate thing in China and India reminded me of a video that I saw where an animal got trapped on some powerlines. So, this guy got a long, wooden stick. When he touched the stick to a powerline, he and everyone around him dropped to the ground out cold. There was no arcs or flash. I guess they all survived, but it was a really stupid thing to do.
Hmm. With a bit of modification (safer fuse holder, safer lamp holder) you could stick that on the end of an isolation transformer & Variac and have a nice little current limited test supply for old valve equipment hehe
Feel like ive seen a similar thing but it was made by my instrumentation teacher when he was an apprentice decades ago to test equipment without blowing it up
I bought a Chinese Ozone Generator... because BCDC told me to. Printed on the front is the most awesome Chinese Product warning ever. The Warning States: DANGER - EVACUATE ALL LIVING THINGS BEFORE USE The product works amazingly well. I would have purchased it just for the warning anyways. XD
I use a thermal imaging camera and flick the swich on/off quickly and see if anything heats up. Doesn't help with a dead short but can prevent a lot of catastrophic failures. Then I keep the switch on longer until I know for sure nothing is going bang and release magic smoke.
It’s been a common thing to build for decades if you’re doing electronics repair. This one isn’t the safest and it definitely isn’t intuitive to use without opening it up first. I think I’d rather make my own if I needed to power up a sketchy circuit.
@2:23 - Furthermore, if you are lighting a load with you body through, say a cut neutral in a knob and tube setup, that current draw is going to bite a WHOLE lot more. When rewiring old houses, you could cut through a neutral that powered a whole host of items. If you touch both ends of those neutrals, the draw just adds that element of "shite!" to your day.
It's great when a glass fuse briefly becomes a little arc lamp.
Nah.
Love it when they turn into an oldschool cameras flash 📸
Extra high intensity discharge! 💥
A small continuous plasma chamber.
@@NinoJoel 200kW of power from a tiny flash lamp. At least for a few ms
expensive light
from that arc lamp
it's like expensive noise
Ha, it's a dim bulb tester like we use for old radios and TVs. Except somehow even less electrically compliant. Excellent.
“Dim bulb tester” that’s no way to talk about Clive 😂😂🫣
Dim bulb testers are still used in guitar amplifier repair, at least for the ones that are still tube- and transformer-based. (Edit: changed brain-o "amplifier-based" to "transformer-based".)
Probably ought to mention that it only works in that fashion if incandescent bulbs are used. LED's will not offer the same protection that the resistance of an incandescent bulb does. Clive may have mentioned this and I missed it... Either way, its worth saying twice.
😢 Getting more difficult to find tungsten bulbs in the shops. Dim bulb testers and "death leads". The good old days.
@@Steve-GM0HUU Search for appliance bulbs. They're for ovens and other appliances that need bulbs that LEDs can't operate in
"Explosion" in a Big Clive title is an immediate watch.
You clicked on his bait?
@@LawpickingLocksmith .. oh yes .. hook , line & copy of Angling times .. lol
@@LawpickingLocksmith Big Clive is a master baiter, and I love to watch.
I only check video's if t has the word 'pink' in it.
To be fair - it is described as "explosion proof".
This is neat, its what we do when working on vintage TV and radio, which can be prone to short circuit failures typically via paper capacitors.
I looked up the ratings for glass fuses and was surprised that a lot of brand-name manufacturers rate their glass fuses to break 10kA on 125vac, but just 35A on 250vac. It seems absurd, but it explains why glass fuses are the norm in the US.
It's a bit scary to think of someone relying on that 10,000A rating as the sole protection method. Arc flashes can happen at 120vac.
It’s no joke. Here in Canada I remember testing a Japanese 5A 5x20mm fuse on an industrial (just in an industrial rental unit) 240V circuit- the fuse exploded very loudly scattering shards of glass- it must have arced from the end caps. Evaporated metal on the glass shards. The extra length on the old 1.25” fuses probably helps. Bulb is better than heater of course because it is nonlinear- used that when developing a VFD- saved a handful of them expensive semiconductors every time it lit.
Yeah I’ve noticed that too.
I think it all comes down to having the voltage to sustain an arc. 120V can arc, in fact welding torches output less than that, but it can’t maintain that arc across the 20mm length of the fuses.
@@gloomyblackfur399 yes, but sustained arcing at below 150vac(rms) is very low chance. unless it's a gas filled chamber meant to do so or super high humidity and open air( for replenishment of the oxygen rich air with humidity for increased conductivity.
glass fuses are used in minimal current draw devices now days and in smaller devices, or holders which will not burn easily.
@@gloomyblackfur399 And even in 12VDC circuits, if there is an inductive load.
"Explosion proof". Reminds me of an old Goonshow joke. "We just received our first consignment of non-exploding boots". BANG!!! "Blast. A dud"
Back in the 1950's US (and still today in some old buildings) you could screw a light bulb into the fuse box. This was a great trick to hunt down short circuits without wasting fuses.
You can still find such old fuse holders in some old installations in Europe. They use a standard E27 threading, identical as in light bulbs.
@@5Dale65 So the light bulb for testing trick would work in those places too.
Unfortunately so would the wrong value fuse, or worse yet a coin.
@@davidg428830A fuses screw in to 20A but don't make contact because it has a more shallow tapered center. 20A fuses will work in a 30A socket. They have a steeper taper to reach into a 20A socket.
CENSORSHIP
@@davidg4288The threads are the same, but a 30A fuse has a more shallow tip taper than a 20A, so the 30A does not make contact in a 20A socket.
Double pole switch? Thats the premium stuff you got
Looks like a double throw, shits off both lines.
oh, it's a dim bulb tester... can be used as one for old TVs.
Tungsten bulbs are very useful as surrogate fuses , well worth having one inline when powering up an unknown device.
They don't blow at their rated voltage, only good for current limiting, and passing current. Could work if using a 12v bulb for example, but you still run the risk of passing current through an arc flash when it burns out or explodes.
Yes.....Two 100 watt 240 volt tungsten filament bulbs wired in series are useful in testing for incoming 440 volts or 240 volts by how Bright or Dim the bulbs light up .
@@kelimikethat’s the idea.
If there’s a short circuit, it just lights the bulb and still limits current to less than an amp, instead of blowing up your circuit with a few hundred amps of fault current and then blowing a fuse.
To be clear, this whole setup would be plugged into a receptacle that is itself protected by a circuit breaker.
@@deltab9768 The idea was stand in as a fuse, and then completely fail as a fuse?
A fuse is supposed to open on a short circuit fault.
A lighted series bulb is not a way to do this. It is a way to test for short circuits, not protect from them. This is only a great tip for someone who uses fuses to test for faults. They would go through fuses quick, so in this case, yes, use bulbs to test faults, not fuses.
@@kelimike I don’t think anyone is suggesting that this is a 1:1 replacement for fuses.
Yeah he said “surrogate fuse” but this is clearly an additional current limiter, for a situation where you think there is increased risk of a fault, but you can’t test it with a meter because there’s voltage and frequency dependent components like transformers. In the event of a fault it will limit current to a less destructive value and (depending on wattage) will prevent damage to the equipment that a fuse would not prevent.
At a certain point you’re arguing against his choice of two words, not against the concept that’s pretty easily understood.
I built something similar myself, just 2 lampholders in series so i can put a led lamp i have repaired or modified in series with a 60w filament lamp in case it all goes wrong.
I think whomever named this product got the concept wrong, it is not explosion proof, it might be short-circuit proof, as I see a lot of other comments called it a dim-bulb tester... like Mr. Carlson's Lab when he is repairing old radios and such and doesn't know if it will short out.
I hear Explosion proof and I think of "intrinsically safe" I once wired an control panel that needed everything in it rated as such, that was my first time ever dealing with this concept and I learned a lot. We used relays with contacts that are rated for use in explosion environments... You can bet these aren't cheap.
Quote: "The standard ensures that an "intrinsically safe device" is incapable of triggering combustion or igniting any gasses or fuels. To put it simply, you can use it around gasses or fuels without risking static electricity or heat discharge from the device igniting the surrounding volatile gasses, powders and liquids."
the "explosion proof" probably comes from a machine translation from chinese. That's how most funny names of chinese stuff happen
@@marcogenovesi8570 Yes, exactly... that is what I believe happened too. I've seen a lot of funny examples... some cannot be said in "polite" company. LOL
The first time I encountered the phrase was in a factory building that worked with flammable solvents, it had "Explosion Proof" light switches. Big black cast iron things with a knob that went "CLUNK", like something salvaged from a WWII submarine. I remember thinking, if the factory ever blows up, these switches will probably be the only thing left intact.
Yeah, ATEX stuff may be many things, but cheap certainly isn't one of them!
@@marcogenovesi8570 That does indeed produce some outrageous results! Of course, when you have items such as hand grenades traditionally being called "divine bone dissolving fire oil thunder crash bombs", you may run into some issues.
Oh it’s a lamp limiter. I assume you have watched the various valve radio repair channels including the ones I spaffed off several times. Still not many tools that can do what a lamp limiter does, an amazing bit of bench hardware for people like me that repair mains equipment
I use an AC labsupply, but before that I used lamp limiters combined with a reset-able adjustable fuse (DIY build) You need a big lamp because otherwise the voltage-drop is to big for many smps (and that is what I find in 99% of what I get on the bench)
The first time I read your post I thought 'well, that person really, really likes valve radio repairs'... Then I realised my brain had inserted a rogue "to" near the end of your second sentence.
When I took Radio Shop in High School in the 1960s we would build and test small tube radio receivers. There was a special test bench we had to use- there was no power at our work stations other than for our soldering irons.
The test bench had an antenna connection and a speaker we would connect our receivers to. The power socket had a twenty watt bulb in a ceramic socket screwed to the bench in series with it. The teacher explained what it was for on the first day, and warned us that any student who plugged their radio into any other socket in the shop would be immediately failed. Nobody tried him on it despite typical teenager stupidity.
@@GothBoyUK I have done so much valve radio repair I moved on
Connecting a high watt bulb (like a headlight bulb) in the place of a fuse is an old automotive electricians trick for locating short circuit witout wasting fuses. Just disconnect things one by one from the circuit until the bulb goes dim and the rest of the circuit starts working and you have found the short. Very handy in circuits where there are a lot of consumers like the marker/side lights on a truck or a trailer.
The irony is, this inline lamp box is probably a lot safer than some of the dubious "test setups" I've seen over the years of people running a bulb in series with old tube based TVs & radios (current-limiting to not make old waxed paper capacitors turn into little flame generators), though even this one still has its' safety issues, but, it's expected from the country of origin it seems.... :P
With one pin of the non-polarised plug having 1cm exposure it is a death trap!
@@LawpickingLocksmithno one died in my 1980s household with those 'death traps'. Metal lamps, not grounded, non polarized and no one would unplug them when changing the bulb 💡
It depends on luck but even some dim bulb test lamps have too high wattage to prevent transformer damage due to shorted HV load - especially on smaller equipment that has very few tubes. For foolproof mains-powered testing you need an AC bench supply - voltage- and current-regulated.
You get one by attaching a step up transformer to an audio amp fed with a 50Hz or 60Hz tone. The current limiter further limits the amplitude of the incoming tone. The amplitude modulator doesn’t need to be linear since it’s in a closed feedback loop. So a resistive divider on amp input, with an LDR on the grounded leg, is all it takes. When the output current is past a threshold the usual op-amp starts driving a LED that reduces the tone amplitude via the LDR. Super simple and effective.
Agreed, my homemade tester made of cardboard and hot glue is less safe.
Hi Clive, another informative video. It is always to interesting to see what is inside of piece of Chinese test equipment!
With that non-polarised plug there is a 50% chance of the exposed base of the bulb being live!
Nice!
Easy fix - just chop the 2 pin plug off, and put a UK 3 pin mains plug on.
How can it be polarized if the mains are AC?
@@gabrielv.4358 Hello, because in the UK the Neutral will be at or near earth potential and the Live will be at 240 volts with respect to earth
@@DavidVR2More correctly, the live wire will sinusoidally alternate 50 times per second, between+320v and -320v with respect to the neutral wire, which should always be at 0v. It's 320v, not 230v, because 230v is only the RMS value.
hey BC, me again. i did a thing today which has eluded me for months. despite doing things far more complicated, a year ago i saw your ancient instructions from the BC site from the tiny bandwidth days for the joule thief and it never worked. i always put it down to being ham fisted, and being crap at winding inductors. but today i thought i'd get to the bottom of it. as soon as i thought about it it was immediately apparent i had in the past taken no pains over the winding polarity. 1 minute with voltage supply, a meter, and a sharpie and it was all good. i am still smiling from lighting a white led with a mere .7v.. it was lovely. seeing how much more readily it turned off rather than on. and the way the duty cycle + changed increased with increased voltage. brilliant. i have had a whole day of fun.
Speaking of light bulbs, we made a board to test e-bike batteries. This has 4 car headlamp sockets on a wooden board and a terminal strip. It can be wired for 24V, 36V or 48V batteries. Each bulb is about 50W so the total is about 200W. A good battery should last about 1 hour. When it is on full power it looks like an EZ Bake oven.
A factory-made dim bulb tester. If only the connectors were rated for mains voltage (being speaker terminals, they are not) and a socket outlet was available...
I've got a pretty advanced test setup in my lab. On top of three switchable dim bulbs of different power, it has a separation transformer and a variac, both with true bypass relays... and a voltmeter and an ammeter in line with the circuit.
Arguably more advanced and better made than Paul Carlson's! That's Keritech level of over-engineering :)
Yours is definitely more advanced than Mr. Carlson's. I've only ever seen him use the same two bulbs in parallel no matter what the DUT is.
I got curious as to what the rating of "speaker terminals" was, so I had a look on some suppliers and I found a pair on farnell than claimed a 1000 VAC rating! Stock code is 2911029
Your comment about glass fuses is a revelation to me. Almost every piece of consumer electronics I've ever opened has a glass fuse directly on the mains input. It's rare to find a ceramic fuse.
Back in the 90's working at a consumer electronics repair shop, we had a similar setup for testing equipment so if you were say, working on an high powered amp and just replaced the very pricy amp transistors, but weren't 100% sure why the blew in the first place, it could save you from having replace them again!
On a side note from the same era; in the Bose Acoustimass subwoofers that were very popular at the time, the used several small bulbs inline with the speaker to not only protect it, but also to sort of "round off" any clipping, making it sound similar to it being powered by a tube amp. It was fun to crank them up a see the lights flashing with the beat!
I think they used an aircraft lamp in some speakers as a PTC limiting element. As the lamp got brighter it increased in resistance.
I’d like to see ElectroBOOM test the “explosion proof” claim 😂
Reminded me of the ballast lamp system we used in telegraph circuits, although the resistance in the bulbs rose as they lit, avoiding the need for a fuse.
With the addition of a polarised plug and some labels this is a neat little dim bulb tester essential in any repair lab. Saves fiddling with sockets and wiring to make one yourself.
0:23 This is a Euro plug, type C. This is used in many countries. If you have a small screwdriver and can overcome the shutter, it will even fit into English sockets.
Not to be confused with the UK shaver plug (search Wikipedia for 'BS 4573' for the comparison) - although they look similar at a glance.
Scottish and Welsh sockets too I'd guess.
Two things to consider 1. BS1363 plugs have a fuse for a reason, we use higher current sockets than most places. 2. The pins on a Europlug are sprung inwards and the tips of th pins are bigger than the shaft. Combined with the way the contacts are designed in a typical BS1363 socket this can lead to europlugs getting stuck.
If you must do the screwdriver trick then please at least do it on an extension lead rather than a socket that is part of the fixed installation, so you will have the fuse in the extension lead and so that if it gets stuck you can unplug the whole extension lead.
So it is a dim bulb tester. I made one for myself last month. Useful for testing second hand hifi devices of unknown condition.
Plug your hifi speakers into those speaker terminals. They will create a sound like never before!
Loud, but brief!
@@zebo-the-fat hahahaha
Make sure you’re on a 32A circuit, as near as possible to the breaker panel, and the bulb bypass switch is closed for the maximum audio experience!
@@deltab9768 hahahahahaha
A sound like never before .... and a sound like never again.
Speaker terminals and 240v blows my damn mind dude 🤣😂
You just demonstrated a "Dim Bulb"Tester" as used by folks restoring old vacuum tube radios to detect if there is a direct short across the line and limit the current to the radio.
Never in my wildest dreams would I imagine that I would have seen something like this on this channel without a schematic!
as someone who works with explosion proof electrical installs in the fuel industry... i can DEFF say... we might want to get a 2nd opinion on Temu descriptions before assuming accuracy in their claims xD
Back in the early 2000s as a broke teenager i used to use the same principle on my hacked up electric scooter. It didnt have any sort of speed controller, just a large relay that gave the motor full voltage from the battery. Kept burning out motors so used a couple of high beam headlamp bulbs in series with the motor as a poor mans soft start. Then had a second relay to bypass the lamps once you got upto speed.
Worked an absolute treat
I learned this trick from a friend who does live music events and I often help him repair amplifiers. I made myself one of these with a single mains outlet, The little speaker terminals look quite handy! I might add them to mine
Another set of clip-ins for the load socket could be used for series current limiting caps. Or use an led bulb to serve as a current limiter for smaller test loads.
Once again I learnrd something very useful,I never re aliased glass fuses were not really for mains voltage. Thankyou
I have used the same system for years for repairing amplifiers, a 150watt lamp in series with the supply.
It will glow briefly until the power supply caps charge up, but will stay on if the bridge rec or the output transistors are short circuit.
Play the big clive drinking game (TM). Drink a shot every time he says "I Shall"... Last man standing wins.
Since I can buy all the parts from AliExpress right now, I have to conclude this is someone's DIY project.
With a couple of hundred bucks, a savvy builder can have custom tooling for ABS injection and make their own custom enclosures.
They have the entire Shenzhen electronics market to sell to. If you are Chinese in this field in Shenzhen, you're making a killing.
Given the non polarised plug and the exposed ES bulb holder, you could be making a killing in more than one sense!
I live in a 220V country and cheap computer power supplies come with glass fuses. Can confirm they explode pretty spectacularly.
There also the risk that metal vapour from a blown element in a glass fuse can plate the glass leaving a high impedence path from live/phase that might give the impression that power has been disconnected, but which will still give you a nasty "tingle" should you touch it.
Could it also generate enough pressure from the heating to turn that screw cap into a bullet?
@@jamestappin4741yea I think pieces of that cap are going flying if enough current keeps arcing across the fuse. The inner plastic of the fuse holder would evaporate and build up pressure.
I had never thought about a blown fuse getting plated with metal and staying conductive.
That’s kinda scary since even if the short circuit is stopped, you can die from less than 1/8 amp of current.
yes. I built a quite similar looking contraption when young: switches to individually turn sockets on and off for computer components. I felt like commanding a space-ship! Until one of the switches got so dirty it shorted out and pulverized the glass-fuse I had used with a huge bang.
Thing looks like an electric chair controller. Probably about as safe as an electric chair too
Oh a dim bulb tester, a bit much for what it is, believe those should be used with as high a wattage bulb as you can get, and the tungsten ones are harder to get now in the UK or Europe, certainly not in the shops any more 😑
Why not see just how much a speaker terminal can really take? I should think they could do at least 500w relatively easily
They are hard to get here in the US also. You might be able to get some 25 watt appliance bulbs, but I don't think I've even seen a 60 W bulb in years. And forget about 100 Ws.
I had a similar idea on my test panel at the bench when I was an electrical apprentice 40 years ago on the docks. It had a 250w lamp on the live side connected to a test rod which was a brazing rod on a long piece of wire. The vice was grounded and it never failed me. Even had lamps in series for the 3 phase stuff. Wouldn't work now with ELCB's of course.
This setup is sometimes done in technical schools with a ceramic cone screw-on resistor instead of a bulb...
You know it’s gonna be a good one when the video starts with “non-polarised plug”
So... every video in mainland Europe (Schuko / Europlug are both on-polarised) is a good one?
In the RC hobby, we call it a Short Saver. Essentially an automotive bulb in series with the LiPo battery tests your soldering and components the first time you power it up. LiPos definitely don’t like shorts 🔥
I never knew how these things worked. I learned something today. 👍
Ha! It's a dim-bulb tester! I had built one of these a good 25 years ago for working with my antique radios and TVs before I had a Variac. The higher the wattage of the bulb used in the test socket, the more current will be allowed to pass through the device under test. Resistors could also be used, but the bulb also gives a visual indication.
This could be for use in stores too. In the Philippines at least, the staff in a store will demonstrate that the product you are buying is in fact working, before you take it home. Be it a TV or a light bulb, they will plug it in and show you. I don't know if it's the same in other countries.
the tube radio people call this "restricted power". the Incandescent bulb with the cross switch for unrestricted power is common in repair shops since the 1930ies. but they used to have proper isolation transformers too, so live/neutral are not referenced any more. (as long as you do not mess up via the ground of the RF connector or the ground of the oscilloscope, iow: you need another transformer for the oscilloscope and a ground free RF transformer too in a decent workshop setup.)
In the valve amplifier repair community this would be called a "dim bulb tester." In general, if the _must be incandescent_ bulb goes dim, at least you don't have a dead short.
Random Chinese Product: "Explosion-proof!"
Big Clive: "I'll be the judge of that." 🔥
Yep, brings me back to electron beam TV service, when we used a 100W bulb with 'gator clips to jump fuse holders to check if we missed a shorted component...
These things just get more interesting.
When they said "explosion-proof", what they meant was, if it explodes, there will be proof of an explosion.
This is also known as a "dim bulb tester" commonly used in testing tube/valve equipment.
"Explosion Proof" sounds like a challenge to me...
I think something that's designed to not explode when you use it, is the least we should be demanding of our products.
In RC models, these are called "smoke savers". They keep you from accidentally shorting a big lithium battery.
Oops there goes another one, Oops there goes another one. 😂😂😂
Interesting bit of kit! That 20mm fuse can easily be replaced by an HRC one, and there's enough space there to put in a longer fuse holder, offering better protection. Alternatively go for one of those push button re-settable breakers if you trust the ratings 🙂
In the rc world this is called a "smoke stopper", as it will prevent stuff from smoking when there is some wiring error
good idea, bulb(filament only) current limiter, i and many others strongly recommend using one when resurrecting valve tvs and radios
Functional, yet horrifying! Perfect for Big Clive test bench demonstrations.
It's called a dim bulb tester, and it's often used with a variac and isolation transformer
close the bypass switch with the jumper in. If you insist you may use a finger extension to avoid injuries.
I’m using a similar home brew box to test tube radio’s… you never know how far the supply capacitor is gone. Works fine. Mine by the way is a lot safer then the Ali express type you show here.
Some old armature testers also had a built in continuity tester. It was nothing more than two probes connected to the mains with a low wattage light bulb in series. Somewhat scary, especially if someone replaced the bulb with one of a high wattage.
My dad always used a bulb in a holder screwed to his bench to test things. Inspired by your channel I recently knocked up test box, although mine is earthed and has an RCD plug, circuit breaker and a power meter module, output is to a UK socket rather than bulb holders. I did need some quick terminals for hooking up leads and despite searching and searching, I couldn't find anything other than those speaker terminals so used some too. So useful for checking wattage and PF of new lights
I presume you know about the CLIFF Quicktest which Clive often uses. If you want a cheaper solution that's safer than speaker terminals I'd just use some Wago Lever Nuts.
@@eDoc2020 Yup know the Quicktest. Too expensive! Fortunately my device is only for me, kept locked away and I know what I am doing. Cheers.
A pre-fabricated dim bulb like this is only good for the general public if they show on top a drawing of the connection lines between elements. If not they could be confusing and dangerous to some.
Came here for some explosions. 🔥🔥
It's very stylish indeed. They are really into the white theme. White case and white wires accented by the black sockets. I wonder if they make a pink one.
F.A.O. BIG CLIVE :D
Have you ever heard of a drag racing Henry hoover? well, on my way home today one of the house locally hat dumped out a yellow hetty hoover, now I love henry hoovers and the company itself, still family owned in the UK, have since I was a kid in the 80's, a true testament to robust modular design and so I know how to fix them up. Have done for folks for a while over the years, anything to stop people buying a bloody Dyson, made of tissue paper by a tax dodger.
Anyway it had no wire so I stripped it, good bushes but the motor sounds gruff as buggery when i wired and ran it, had a look at its windings, free wheeled it and it all looks good so I wondered if there was just crap on the bar, I noticed the bushings while still having plenty of life, were distinctly more oily/wet than my henry. So I went into my tools and my other half a wonderful man called Lewis for the last 15 years, yes we like dorathy too, had purchased a new can of contact cleaner for me, not my usual brand and indeed at times I just use WD40 but this was "made by" WD40 so I figured it would do the job and I blasted the hell out of all of it, gave it a bit of a wipe down and popped it back together.
Interesting thing about WD40... once you spray it onto a surface, the stuff isn't flammable. Turns out that's not actually the case for their contact cleaner... and well... I was rather liberal with it so when I re-seated the motor back into the top housing and turned it back the right way up the remnants of my spraying must have gathered somewhat internally. I flicked the switch on and for the brief beautiful moment before I was deafened it ran like a dream, followed by a VERY Loud POP and a 3 foot green flame that fired out of the exhaust vent. Ah the fun I get up to at 1 in the morning.
try it some time, its hilarious.
Exciting. I'll have to give that a go. There are horror stories of people spraying all the mechanisms in their pinball machine with WD40 (not a good thing to do), and then immediately trying to play it, and setting the solvent on fire.
An advert for a Chinese hifi power filter box was translated as 'bovine pure', got lots of laughs on the forum.
Maybe this is where the word "boom box" came from.
That's a short tester, it's a useful tool for troubleshooting a device that is AC powered and trips a breaker. I've built and used such tools.
This is not a device that could be used in any capacity with an explosive location and meet any code requirements in the US.
If you use this as a short tester and don't understand it and how to keep yourself safe it will kill you.
If you use this as a safety device in an explosive location you could kill everyone in the building and maybe a few neighbors as well.
Thanks for doing these videos and shinning some light on these dangerous products.
Based on some pictures found on aliexpress, the large socket at the end looks like a Westinghouse socket used in the US from the 1880s to the early 1910s.
It's worth mentioning that Sir Clive is worth mentioning
Didn’t know that about glass fuses! It makes me wonder what other simple things I don’t know…
Interestingly some IEC sockets I have purchased before came with glass fuses pre-installed.
Thanks sir, very informative indeed.
Fun fact, China have almost no standard AC plug before 1990, they got Australia like plug, US type plug and also Europe type plug on all kinds of outlet, very confusing, even today they usually buy the power strip (power bar) which accept multiple plug, also means not good, even BT thick square legs is a bit loose, even on fire before my eyes. Back in 20 years ago, I know some Hong Kong invested factory even only use BT type power strip inside for safety, sadly most of them quit China now.
Yeah, power outlets in China are kind of interesting. It is the Australian type with slanted prongs but inverted with earth at the top, along with US flat prong and sometimes Euro round prong. I did happen to visit the British Embassy in Beijing, and I did see they used British BS1363 standard outlets and plugs. Of course that Embassy is UK territory, so they have to comply with UK standards.
I don't know what the Australian type outlet in China is rated to, but I've often seen them scorched and melted around the holes, because they were overloaded. Unlike the UK which prohibits power outlets in bathrooms. Bathrooms in China often have a couple of power outlets. They also have large cylindrical water heaters for the showers etc, might be 2-3kW, plugged into those outlets. Washing machines are often in the bathroom as well.
We can be happy in the knowledge that you will fit a UK mains plug, at your earliest opportunity.
You would have to take it apart though to find out the correct polarity.
And change the flex too.
So much dedication to safety! (Sarcasm, of course) Interesting.
WOW a new name for a a dim bulb Tester. I have one on my bench. it plugs into my variac. and the piece of equipment I'm working on plugs into my dim bulb tester.
To me "explosion proof" means electrical enclosures, i.e. cabinets, conduits, switches. sensors, and motors, are sealed in such a way that flammable gases or vapors can not get in to cause an explosion if an electrical spark happens inside.
That tester looks more to be a "spark proof" test box.
I recently built a (very) poor-man's current limiter by splicing one extension cord into series with another then just plugging it into a desk lamp with incandescent bulb in it. I can easily add more lamps to help adjust the wattage.
Yep ! ( Thanks , previous comments ) .. the " dim bulb " tester is the MOST USEFUL bit of electrical kit .. not only will it stop you blowing fuses .. but .. you can test [ unmarked ! ] transformers with safety ( for YOU ! .. and .. the transformer ( ? ) .. just use a ( low wattage tungsten bulb ) for tiny ( 1 inch transformers ).... tried - n - tested ............... DAVE™🛑
The "tungsten filament bulb in series with the supply" method is also sometimes used when powering up old valve radios. The filament naturally has a positive temperature coefficient of resistance; which means the hotter it gets, the less current flows through it. This gives it some self-regulating effect against voltage variation. It also acts as a crude milliammeter; and with a correctly-functioning set, you can see a bright burst corresponding to the inrush of the valve heaters which then dims as they begin to warm up and the resistance increases, until the rectifier valve begins to conduct and the light bulb gets brighter again -- perhaps dimming slightly once the smoothing capacitors are charged. If there is a fault anywhere causing the set to try to draw too much current (such as the DC-blocking capacitor connected to the grid of the output valve having died of old age, causing the valve to turn on hard and pass excessive current through the speaker transformer), the bulb will light brightly, but the radio can never get more current than enough to light it fully, which serves to limit the energy available to do any damage (energy which, in the worst case, will be distributed to each piece of shrapnel as 0.5 * m * v ** 2).
It's just a shame tungsten filament lamps are so hard to get nowadays, because idiots kept insisting to try and use them for general illumination .....
When I was an apprentice I'd hook up 2 incandescent lamps and used them as test probes for polarity and checking 415v lol
A useful piece of gear, assuming you know what you are doing. Though, I do worry about people who don't know what they are doing buying things like this who may end up injured or worse.
A bit ironic that a "safety" device is so unsafe :D. You can make a dim bulb current limiter for dirt cheap and be safer than this thing. Even just an old bulb and a socket/cord can do the trick.
The high mortality rate thing in China and India reminded me of a video that I saw where an animal got trapped on some powerlines. So, this guy got a long, wooden stick. When he touched the stick to a powerline, he and everyone around him dropped to the ground out cold. There was no arcs or flash. I guess they all survived, but it was a really stupid thing to do.
I use a 100w series lamp for when I test TVs works a treat thanks Clive nice gadget 😊
Hmm. With a bit of modification (safer fuse holder, safer lamp holder) you could stick that on the end of an isolation transformer & Variac and have a nice little current limited test supply for old valve equipment hehe
Feel like ive seen a similar thing but it was made by my instrumentation teacher when he was an apprentice decades ago to test equipment without blowing it up
I bought a Chinese Ozone Generator... because BCDC told me to. Printed on the front is the most awesome Chinese Product warning ever.
The Warning States: DANGER - EVACUATE ALL LIVING THINGS BEFORE USE The product works amazingly well. I would have purchased it just for the warning anyways. XD
I use a thermal imaging camera and flick the swich on/off quickly and see if anything heats up. Doesn't help with a dead short but can prevent a lot of catastrophic failures. Then I keep the switch on longer until I know for sure nothing is going bang and release magic smoke.
Is this Gizmo an answer to a question you have not thought of yet ?? 🤔🤔🤔
It’s been a common thing to build for decades if you’re doing electronics repair.
This one isn’t the safest and it definitely isn’t intuitive to use without opening it up first. I think I’d rather make my own if I needed to power up a sketchy circuit.
@2:23 - Furthermore, if you are lighting a load with you body through, say a cut neutral in a knob and tube setup, that current draw is going to bite a WHOLE lot more. When rewiring old houses, you could cut through a neutral that powered a whole host of items. If you touch both ends of those neutrals, the draw just adds that element of "shite!" to your day.