Teardown of an LED Traffic Light Module
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- เผยแพร่เมื่อ 13 พ.ค. 2018
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• The LED Traffic Light ...
In this video, we explore the innards of a GE LED traffic light module from, well, some year. I have no idea there weren't any date codes anywhere.
Another advantage of coloured LED is like your green it has no colour when off and just lit by the sun. That way you can't accidentally mistake which light is on.
Raymond Barbour. Wow thanks. I was wondering why the plastic is clear transparent. :)
Very high attention to detail
That also explains why the "heat sink" (which also looks like a reflector) is black instead of bare aluminum. I was wondering what advantage making black had when you would want to reflect as much light as possible out the lense. But if you're trying to avoid any light coming IN the lens going back OUT, black makes sense.
another interesting note about "traffic light green" LEDs. they are NOT a typical green LED! they are considered a "TRUE GREEN LED whereas other run-of-the-mill/typical LEDs have more "red" in them.
UK ones have a cover over them so they cannot look on
I immediately got the ''Big Clive'' deja-vu as soon as you've switched to the top view camera.
Righty-ho then! :P
.... or i might be mistaken, i'm not so sure. I'll be back momentarily ;)
MIKIVELES369 oneee moment please..!
big clive tends to draw out the scematics while babbling on about how it works
But he didn't set his lab on fire and then calmly exclaim "One moment please."
As to the green one not having a green lens - that is extremely common in my city. The red and yellow have red and yellow lenses, but the green one has a clear lens. *(For LED-upgraded intersections.)
The best reasoning I can come up with is that way if you have the sun behind you reflecting off, you won't accidentally see the green one reflecting the sun, and think it's lit. You will only see the color green if it is actually illuminated green. Reflections on the red and yellow may make you think they're lit red or yellow - which is a fail-safe condition. "Oh, shoot, I can't tell if that's a red light or a yellow light!" Either way, you stop. You don't want a fail condition to make people think it's green when it isn't.
Wow great suggestion lol I was wondering that too
Note that is my semi-educated guess. I have no inside knowledge, it just seems a reasonable assumption for why it would be clear. Also that it isn't just that his sample happened to be "different." It is an actual design choice to differentiate green from yellow and red.
+Anonymous Freak lol I was looking at the GE spec sheets and every color is available in with clear lenses. It's a matter of preference it seems. That is, such reasoning is left for the local government to do. If they consider green is better left clear, then so be it. The other way around probably wouldn't be recommended though haha (eg. leaving the red one clear)
You are right, the local newspaper gave the same reason why the city swapped out half of the lights on many intersections. The lights installed where especially bad when facing the sun because the green was actually more reflective than the other colors.
Actually, where I live, in normal operation the traffic lights have 4 different states it can shine.
Green - Go
Yellow - About to turn red, stop if possible
Red - Stop
Red and yellow - About to turn green, get ready
The LED board was made in the 36th week of 2008. You can see the date code on 10:37, right under the LUMILEDS brand. The power supply board was made maybe in the 21st week of 2004, as seen on that code on the right top side of the board at 10:37 as well, but you'll have to check the ICs on the board and see their date codes to be sure about that. (Every 4 digit date code is written in the following format: WEEK/YEAR, as in the LEDs board, 3608 (36th week of 2008), other example would be 3691(something that was made in the 36th week of 1991)).
Thanks for that! I'm not very well-versed in that sort of thing.
I agree completely with you. That is the date code for the power supply board. I didn't see it before, otherwise I would have inserted the correct information in the first comment.
I actually thought that it would have been weird that the power supply was made way before the LED board, but since I didn't located other date code on the board, I assumed that it was "encrypted" on that long code, because some board makers do that sometimes, but now i've seen the correct date. So, we can agree that they were made together.
mreich98 I was going to say the very same thing.
Dennis Fluttershy
I have done a little research, and as far as i can tell (i could be wrong of course), date codes for electronic parts are not regulated by the ISO; instead it appears to be controlled or managed by the EIA - Electronics Industries Alliance.
I wasn't able to find out if those date codes are referring to the first week of the year, or the first week with 4 days or more. Sorry about that.
In the end, though, i don't think it matters very much; after all it can't be more than 3 to 4 days off, and i think that's good enough for most purposes.
I love the gag of having a CFL as this channel's icon.
The to be created in future editorial channel will have a circline tube
@@mrflamewars Which channel should have LEDs and tube fluorescent lamp?
Big Clive would be proud.
MIKIVELES369 No he wouldn't, there was not nearly enough alcohol, sweets, or innuendos involved.
That was a pretty poor impersonation though. Not enough beard. :-)
No he wouldn't - One massive difference - BC knows what he's talking about. This was one of the most painful and contrived BS sessions I've seen. There was even confusion as to whether it's Leds or L-E-Ds, lord give me the strength to avoid these empty starstruck wannabes who think a camera is all that's needed - he should stick to what he knows - if he knows what that is.
@metric ruler No offence but , You Know, That's Just, Like, Your Opinion, Man! xoxo
“The Dude abides.”
11:14 The real reason Yellow takes so much power, and Green slightly less so, is because in the day, they need to be brighter to be seen over ambient sunlight (which is a greenish yellow). You can notice this at night when the green and yellow are blinding but the red is normal.
One other thing I've noticed it that the red signal "flashes" brighter for a split second when it first illuminates. I guess as a sort of attention getter. ~2-3 milliseconds. At least around here.
Exactly. Look at the specs sheet referenced in the first video and you will see that while the yellow light uses more power it also emits about twice as many lumens as the red or green.
Who is this impostor?
Better file a copyright claim!
I find the CFL channel picture quite amusing =D
Doppelganger? ha ha
If you can give me GE SKU number from the label on the back of the unit then I can check when and where was it produced. Actually I'm working for GE on transportation light project (as well)
I want a Tech Connect 3 just for another bulb joke.
Nice teardown! It's worth mentioning that in some cases, each light will have more than a 50% duty cycle. Many lights at intersections between large and small roads remain in one state until the presence detectors notice a car on the smaller road, and then switch over. This is also true at some pedestrian-only intersections where the light is controlled solely by the pedestrian switches.
It would difficult to estimate the average duty cycle for every light at every kind intersection. But because of their application (safety) these are engineered and tested for 100% duty cycle in all sorts of environmental conditions.
95% of intersections in all the countries I've been to use a time system, and will activate even if the intersecting road is empty.
I think my town has one rigged backwards. A larger, higher traffic main road intersects a low traffic side road and the light defaults to green on the small road, triggers for like 15 seconds green on the main road. Then goes right back to green for the side road for muuch longer. Its annoying.
Great job on the video! Was definitely getting some BigClive vibes during the brute-force destruction with a screwdriver, just missed the common phase "Other things worthy of note...". I like the idea of this second channel for deeper dives into the tech with a sort of informal approach.
I concur; I'm also one of those people who love to "get inside" of things and see how they work. :)
Brute force and ignorance were used.
Where's that spudger?
Love these kinds of videos. As a little kid I always wanted my own stop light. My parents got me one of those Spencer Gifts novelty ones for my bedroom that used Christmas tree bulbs. As I got older, I realized how huge they are when they aren't hanging 18 ft up in the air.
You definitely need to contact Big Clive! He'd love this :D It's a massive difference to the regular LED drivers he usually looks at, too :O
Email him! :P
You may not be Big Clive, but this video amused me and also made me think - wow, is that it?! Thanks!
FWIW, the capacitor looks to be the distinctive brown of Nichicon’s 105°C range. And that’s basically exactly the cap you’d expect to see in an application like this one.
Will only fail in the wildfire... :D If not even probably.
And Nichicon has a reputation for quality.
The LED traffic light I took apart a while back (11 years?) had a nearly full diameter layout of LEDs, about the size of the first dimpled diffuser you removed. Most likely like the type in the other video where some of the LEDs had failed. I was surprised to see such a small array of LEDs in there!
Lumileds was a joint venture between Agilent (HP) and Phillips Lightning. They had their hands into almost anything LED. My dad used to work there as a technician cutting, doping, & inspecting wafers for the dies.
Phillips bought out Agilent's interests, and moved production overseas and nearly everyone at their Silicon Valley location, shy of pencil pushers, began counters, and cubicle chattels got handed a pink participation prize.
You were right on with GELcore.
"They make high-brightness LEDs used in traffic signals, signs, and automotive applications. *GELcore is a joint-venture* *between General Electric Company* *and EMCORE* *Corporation.* "
I insta-subscribed to this channel as soon as I was done watching your stop light video. Your content is top notch. Keep up the awesome work!
Hah, just as I was thinking ‘someone send Clive one!’ you made the same reference. Kudos, and good luck on chan 2. :) but ow that buzzing hurts so much.
I thought that myself. I want to see Big Clive take one to bits.
Not gonna lie, I was expecting it to be one big circuit board with a huge grid of LED modules. Not this 8 LED modules madness!
I have some units, too, that are thinner, with... hundreds, perhaps, of LEDs? They're not immediately handy, or I'd say more about them.
There are units like that. It’s made by GE. Very nice modules. This is coming from a signal enthusiast
The power supply is constant current, which unfortunately is more complicated than constant voltage. I agree it looks well made. It has to keep the LEDs within brightness spec across a very wide temperature range.
I would also like to mention there's a arrow marking on the back for the installer to position it right. It's there for the refractile grid because it has a rotation bias. The lens emits a horizontal beam when installed correctly to maximize the viewing angle on the ground.
You mentioned the green one being different because it is clear - the red/yellow/clear thing is common. First, if there's one aspect you don't want to reflect sunlight, it's green. Fresnel lenses combined with reflectors are pretty bad at this, but this was more just an ambitious solution for a problem that doesn't exist with LEDs in the first place. Second, clear lenses are much more efficient - why bother putting a colored lens on a colored LED? I have seen a few totally-clear-lens signals, but it seems to be a driver-comfort thing that the red and yellow lenses are colored.
Also not to mention colored lenses also reduce light output and since LEDs already produce the color on their own unlike the incandescents it is all pointless
I laughed pretty hard when you got to the guts there. Expected a few more LED's than that.
You are very detailed and interesting...I have loved traffic lights, streetlights RR crossing lights and most street furniture since I can remember, looking back as a child riding in the back seat of my Dads car always looking at the different traffic light configurations, lenses, shades, etc. and being so fascinated. Funny how that LED driver/power supply has 2-glass fuses, not really a serviceable component in a sealed fixture. Love the tech talk and traffic engineering talks, great info, keep un the great work!
Happy to see a second channel for more in-depth teardowns of items. yes you are no bigclive but as this is only your first teardown video and bigclive has had years of on the job experience (as that he is an electrician by trade and quite often works for theater companies) you did a fine job. Your knowledge will grow with the more you do.
This is interesting. I had some LED traffic lights from here in NZ (current generation ones that are being installed) and they have a massive array of regular high brightness LEDs, shining through small lenses to focus the beam in a smoother pattern (basically just a solid level of intensity). Some of the older date codes were running 5mm through hole LEDs, and the newer ones used an array of small SMD packages with an integrated lens. 250mW rated IIRC.
They were crazily complex compared to the electronics in this too. Running 8 separate series strings if i remember right, all with current controlled drivers.
Construction was a single large round driver PCB, and in front an aluminium/FR4 hybrid or a regular pcb with the through hole led ones. There was a lens assembly with separate individual lenses for each LED in front.
All in all, it was an interesting thing to take apart. Mine were screwed together with a plastic "cup" for the lens, and a cap that sealed onto the back with a silicone o-ring. The weird part is, despite being super overbuilt and very modular, they get replaced and ditched, even when the issue with them is as simple as a blown fuse (which all of mine were) Obviously it was built as a high reliability unit, but it was truly gilding the lily even in that domain of electronic design. I suspect a very lucrative cost plus style contract or something, where the EE responsible got a chance to just go hog wild with the design :D
Anyway, thought you'd enjoy hearing about the differences with lights down under, and keep up the great videos man!
DossKat We used to use that style in the US. Many of them partially failed from what looks like water infiltration. I really liked the look of those first generation units. We use the style in this video now, and I call those third generation. The second generation looked like they had a large array of rectangular LEDs, or maybe there were clever optics involved.
It figures we're using 2 generation old tech in nz hahaha. though I've noticed that in the last few years, they must have upgraded the LED efficiency or power output because new traffic lights seem to be significantly brighter (not the segment style that you were talking about though, I'm guessing they're just better leds in the old style ones.
Oh, another Big Clive viewer :)
EpicLPer
Same thing that went through my mind lol
My thought exactly. Now, wondering if he watches Julian Illit, also. 😁
Or Dave from EEvblog...
I suspect people who watch Alec generally also watch Clive (bigclivedotcom), Dave (EEVblog), Julian Ilett and Fran Blanche.
Chad he mention Julian in he fish tank video.
Nice teardown. I love seeing inside items like this, that I wouldn't easily be able to access myself. Some other things you might consider pointing out in the future:
·Capacitor brands - are they crappy, or name-brand (nippon chemicon, rubicon, etc.)
·Date codes on chips - how old are the parts?
·Chip part number "for those playing along at home" (point out common chips like 74 logic, op amps, microcontrollers, etc.)
·Relay specs and branding - are they crappy, or name-brand (omron, schneider, panasonic, etc.)
·Fuse ratings and types (basic glass fuses, high rupture capacity fuses)
·Measure voltages and currents if you have a multimeter (how much power do those LEDs use? Are they in series/parallel combinations?)
·If you have an oscilloscope, you can probe signals in different parts of the circuit (doesn't apply too much for this teardown though)
(yes, i know i'm replying to a 4 year old comment)
The whole capacitor-brand thing is kind of BS- lots of audiophiles will have their own opinions on a certain brand of capacitor and say it sounds better
That battery pack might be putting out a nasty sine wave, be careful if you’re thinking of using it with older electronics. I’ve had several that were extremely noisy electrically, I really only trust my anker powerhouse at this point.
I wish I had an oscilloscope handy to take a look at it. As it stands, I only have one more use in mind for it. Mostly I got it for the video!
I have an oscilloscope, not because I’m some high falutin’ electronicist, but because damn they’re super useful if you do even hobby electronics.
I highly suggest you consider getting a low end one if you ever considered picking one up, I promise you won’t regret it, especially if you want to show off things like, say, analog video signals, audio, etc.
I know it sounds ridiculous but I promise you that with your level of curiosity, you would not regret it. It would make for some great footage too.
The rigol ds1054z is hackable to 100mhz and it’s a killer deal at $350 right now.
Although the power might be dirty and noisy I don't think modern electronics with switch mode power supplies really care much. I haven't put tons of research into it, but I have seen a few videos talking about it and doing some tests with a scope checking out the crappy some wave (more like an Aztec temple shape), and raising and lowering voltage. Most gadgets these days have power supplies happy between 100 and 240 volts, and it immediately gets turned to dc and put through filter caps, negating any crappy sine wave. Still, do you want to trust a expensive device to a crappy inverter? Guess it depends on how much you trust the crappy inverter :)
volvo09 to be fair his plan was to promptly destroy it anyway, so it likely meant little enough. :)
that has no effect on AC to DC converters as the power is rectified before any thing happens...
WOW, that lens is amazing. And just think that because they're plastic they can be manufactured so cheaply.Augustin-Jean Fresnel would be so proud.
That's a cool power pack, great for testing and whatnot. Thanks for taking that apart, I wanted to see inside one of those style lights too. My town has a lot of the older ones with tons of the domed through hole led's on a board, but we got some of these at new intersections.
It was really cool seeing the inside of that. I purchased an old traffic signal from our lighting control company a few blocks away from our shop and wired up to work in my train room with a controller that changes the signal just like a normal traffic signal. I didn't want to take my depart, but I've always wondered what the inside of those LED modules look like.
I didn't know you had another channel. I'm glad that you didn't have to destroy that light to get it apart. Was nice of you to give BigClive a mention. Both of you two are my favorite youtubers. I love technology and you both do some very interesting videos. Liked and subscribed.
Definitely take more stuff apart this is the good shit
I've seen every video on your main channel and I'll be catching everyone on this channel :) love the less-edited style and hearing you speak in a more 'conversation' style. Looking forward to more of your content
Okay, so I've appreciated your videos on the other channel for quite some time (especially for how OLD you make me feel by explaining things I took for granted to an audience who has never known them.)
But I gotta say, if this channel is more of the same as this video? I'm *super* excited to see what comes next!
Thank you for being awesome!
You should send one to Bigclive
I agree, I myself have tried to sort out just what the hell was going on with that PCB since I have a set of my own. The black solder mask makes it near impossible.
Depends on whether you want to keep it... but maybe completely desoldering one, then sanding it with 1000 grit till the traces pop might be good... for science.
Big Clive definitely needs to take a look at one of these, if only to see what differences might be in a European light. Thank you for an informative video.
I've always been curious about the insides of these too, thanks for showing! I'm another person saying that I do think they are a full set, the green LED lenses here are clear as well. So no worries about that!
Don't ever compare yourself to others! I watch both of you and love both! Your skills are on point with him!
I dug the tear down, I'd be interested to see more of these in the future. Subbed, and looking forward to more from this channel as well :)
I thoroughly enjoyed the informal, Big Clive-ish tear down!
The optics remind me of the backlight diffuser seen in most common LCD backlights.
I have one of those 115v capable power banks! They are, as you say, cool.
Yay fellow BigClive fan!
This is a pretty interesting video; I'm enjoying the more hands-on, in-depth feel. I was just thinking there was something big-clive-y about this video as you mentioned him!
Great video! If you wanted to adapt the modules for decoration use indoors, you could probably swap the driver for one of those cheap eBay 1W drivers to make it a lot dimmer.
6:49 although you were trying to hide that you started to unscrew the screws while the lamp was still plugged in your power-bank, I saw it 😂
Nice to see not designed as disposable (as initially thought they were sealed) but designed for quick repair of the supply or led (probable replace in field and repair in shop).
I also recall technology I first saw in my native California at least 40 years ago: Fresnel lenses. These used conventional bulbs (obviously, in that era) but had a colored Fresnel lens over them, restricting the view of the signal unless you were facing it directly. This was supposedly to keep opposing traffic from jumping the gun by watching the other signals and entering crossing traffic. I suppose they are still around, but I've seen fewer of them lately; most cities now simply add a delay... the opposing signal will go red, but you won't get a green for about 3 seconds.
The fresnel lens is only there to direct the light in the right direction without needing a very high amount of power or a much more expensive (and heavy) glass reflector. Older incandescent levelcrossing lights in The Netherlands used to have glass parabolic reflectors paired with linear fresnels, dispering the light only 15 degrees to the left and 15 degrees to the right, while in the horizontal plane it was basically a parallel beam.
When the lights got converted to LED, most lost their linear fresnels and got a diffuser that just spreads light everywhere basically, but as the hundreds of 5 mm LEDs make sure most of the light is projected in a 30 degree tight beam, the diffuser only makes sure that it can be seen giving a signal even when you're standing right beneath it.
Delays have always been normal at Dutch junctions. We would never give interfering traffic a green light right after a red from another direction, but I wouldn't be too surprised if the many pedestrians and cyclists account for this.
Love this! Please take more things apart! :)
Sometimes you gotta break shit if you want to learn. Old removed car parts are great candidates for this. Bust it apart and see what makes it work!
John Totally. By no means limited to car parts (industrial stuff is high on the list)
That's quite fun. I was thinking "Big Clive" would love to take this apart - but you said it yourself.
Already love your new channel. Liked and subscribed.
I am a traffic signal technician for the state of Texas. Every single signal in the state, with extremely few exceptions is using LEDs. I work in the top 20 counties, and only know of one. If you wish to deepen your knowledge about “everything” federal traffic related, including signal look at the MUTCD , manual in uniform traffic control devices. It of course includes a section on signals. I’ve enjoyed your last couple of videos.
Thanks
Does the MUTCD specifify how bright a light must be from varying viewing angles?
While the MUTCD does not give a lumens specification it does give specification for visualization. Search MUTCD “section 4D.12 visibility, aiming, and shielding of signal heads”. It also talks ability to use louvers to prohibit sight of the signal from anyone except the intended lane user.
BTW when we did use incandescent bulbs, they were 130 watt.
@@badandydavis Thanks for the info. It's nice to see that the standard isn't just prescriptive but also provides rationale and guidance.
What things did you try to block out on the back of the lamps in the beginning? You mentioned name brands and other info later on in the vid, so was there a reason for blocking something on the main product?
He's worried about having stolen property. Not that he stole them (maybe he did) but you can't be sure that the person who did sell them didn't steal them from a government storage room.
As soon as you started to pry open the top lens I thought to myself.... if only he had a spudger like big Clive 😁
It's interesting seeing how these ones are built. I have a red led traffic light I took apart, and it's design has a baseplates with probably a hundred LEDs wired up instead of just a few like this one
Lol, the opening of this video where you are showing off all the lamps felt like the most chilled out shopping Chanel segment
GELcore is a joint- venture between General Electric Company and EMCORE Corporation
I really want big clive to do a tear down now. That is a really complex board just for driving LEDs. There's also a 2 pin connector between the power terminals, so clearly the unit is designed to more that just be on or off on the supply.
The second 2-pin connector could be a 110V feed-through for that optional snow-melt heater. A Clive-style reverse-engineering doodle would answer that!!
Can confirm it is a 110v passthrough, I have a set of these myself.
It's not complex at all. It's most likely just a constant current switch mode power supply. Those look fairly complex, but are quite simple. I do consider them an odd choice for INSIDE a light fixture, but hell, I live in The Netherlands where we most likely do not even get designs like this certified because of the lack of redundancy.
Big Clive would probably be thrilled to dissect that if you sent it to him. You could save some money on shipping if you just sent the board and LEDs without the housing.
The LED-panel is pretty much a standard-off-the shelf product. i have the same kind of modules, just as circular rings with lenses mounted.
Complete shot in the dark here, but my guess as to why the yellow light needs more energy would be perceived brightness and the filter used. I'm guessing that our eyes pick up green and red light better, so we need more yellow light produced to see an equivalent brightness. Also, the yellow filter may absorb more of the spectrum put out from the LED then the red filter.
Actually, our eyes' peak sensitivity is to yellow light, so you would expect the opposite to be true. Street lights traditionally used sodium as less light was requires so less energy expended. The yellow using more power may be to do with conversion efficiency of the phosphors used.. Big Clive would know *sigh*
Gordo Now you got me inerested. I will need to do some research on this as I would assume the opposite, since our eyes have RGB receptors, you would need a minimum of 2 photons to perceive yellow. One to stimulate green receptor and another to stimulate blue receptor. Where as green and red require only 1 photon. Makes me wonder why we would perceive yellow more strongly?
If you look at a frequency response curve for human vision, it does peak toward the top end of the green & bottom end of yellow. A photon of light, be it yellow, red or green, is still a single photon and differs only in frequency (hence energy) - I seem to recall that human red & green cone cells have a fairly wide response bandwidth. Perhaps a fixed number of yellow photons triggers both red and green cones at the same time, making it appear brighter. I'm not really sure. Sounds like some Google-based research maybe required..
Combined with sensitivity of photoreceptors, someone needs to take a spectroscopic reading of the exact color peaks produced by the LEDs compared with incandescent as well; I wonder just how much overlap there is due to incandescent being a black-body radiation light inclusive of all lower frequencies upto its color temperature.
Hi Alan.. Having read the Wikipedia article entitled "Color Vision", I see that the human rods, responsible for monochromatic, low-light vision, have peak sensitivity at 550nm which is yellow. I suppose that if the same light falls on both rods and cones, the outputs could combine to give maximum sensitivity at that wavelength. It also explains why low-level light is often chosen to be yellow. I also noted that the humble pigeon has 5 types of cone receptors and can differentiate 1000 times more colours than we primates can with our measly 3. It's interesting to try to imagine how it would be to see the world in that way...
Great video Saves me from having to climb a pole to take apart one to see how it works. Thanks.keep up the good info!
I must say, it surprised the heck out of me when i saw how few LEDs this unit actually contained; i was expecting a "Sea of LEDs", especially when i saw the 2nd layer with all those little lenses, they reminded me a lot of the tiny ones in early pocket calculators like the TI-30. I guess this model won't develop "dead pixels" like older designs, which is a good thing, i suppose.
Anyway, great new channel, I'll be looking forward to more teardowns in the future, here.
There are so many different designs out there... In the Netherlands, we tend to use a PCB populated with a whole bunch of 5 mm LEDs. This not only to distribute heat better, but also make it more redundant: if one LED fails open, only 3 or 6 LEDs will go out while the remaining stay lit.
My levelcrossing lights are also made like this and draw considerable power, almost the same as the incandescent version, but my lights are fairly old. Besides that, I wouldn't be too surprised if the current drawn is done on purpose to prevent the controlling electronics from signalling a failure condition. Many things in railroad design are completely failsafe.
Like for Bigclive reference
Big Clive is the man lol.
Hi, I am guessing that the one you took apart is a newer design with fewer, but brighter LEDs? My NC city put in the large array type 10 or so years ago. Maybe 15. They started getting failed LEDs a few years later, but still functioned. Though with dead LEDs they looked like a bad 8 bit video game.
CJ Carpenter I think yes and I think it's the superflux leds or something similar, really really bright.
Where I live they installed the 1st generation large grid arrays, that looked like round LEDs, followed by 2nd generation large grid arrays, with what looks like rectangular LEDs, followed by these incandescent look LED units. We tend to be early adopters, and right now, Charleston, WV is installing 106 high mast LED streetlights with 401 heads on our interstates.
I got some left turn traffic signals in 2017 because the city is replacing them, due to outdated signals, that means they are starting to rust, so the signals came with first generation red and green LED arrow modules and there still going strong, non burned, they where made by Electro Tech in 2003. Btw the green module has a screw in base and you screw into the incandescent reflector. Even though the led burns I can re-solder them with new led. lol
I don't know, I was seriously impressed when you opened it up, just those 8 LEDs are all it takes?! Optics for the win!
I liked this video especially when you showed us your hands. This is seriously a compliment and not meant to be weird even though it’s going to sound it, but you have really, really pretty hands. You should be a hand model. Thanks for showing us the inside of the led green light.
1:00 I wouldn't assume it's from another set, i've seen a few traffic lights that have coloured plastic for red and yellow but clear plastic for the green. No idea why they do that.
Edit: thinking a bit, maybe it's to make it extra clear when the green light is not on if you just can't see any green at all?
It's up to the state purchasing the unit. The datasheet states you can get the lights with or without a clear cover.
The LED modules come in "tinted" and "clear". The idea of a clear lens is to eliminate what is known as the "sun phantom" effect. This happens when the sun, low on the horizon, hits the lens and makes the signal look like all of the indications are simultaneously lit. This was especially a problem with incandescent signals, because the sunlight would go through the lens, hit the shiny reflector, and bounce back out, making it look lit. With the clear lens, you don't see the color of the indication until it's illuminated from the colored LEDs. Thanks for the nice tear-down video.
this pic www.mytrafficlights.com/wp-content/uploads/2015/12/SunPhantom.jpeg from this article www.mytrafficlights.com/clear-led-light-in-the-traffic-light/ shows a good example of it
Please post another video if Big Clive decides to take a look at one of these for you!!
4:46 Knew would be able to open w/o breaking outer “shell” with screwdriver (what I prefer using are nylon “plastic” car clip/panel removal tools for things like this, as helps to not chip, crack…..damage anything while taking a peak. Or at least mitigating damage if does happen) as have repaired some old incandescent ones in my electronics repair business long ago.
What I didn’t know about these new LED ones is how few LEDs are actually inside. Thought for sure would have 16-22; wasn’t expecting to see just 8….COOL!
Thx again for making info/learning FUN & COOL (if only you were my science teacher decades ago when in school; wouldn’t have been sleeping and bored during class😉)
✌🏻✌🏻
Haha, all these years since they started replacing the incandescent units with these, I thought those dots on that dotty lens were just a big bunch of individual old-style round LEDs soldered into a big circuit board! So now it's cool to finally see inside one of these!
Depends on where you live, because here in The Netherlands, they really are big PCB's just mounted full with 5 mm or so LEDs (could be SMD by now, don't know, but the number's still the same)
We use different diffusers here and most likely have the LEDs use their distinctive beampattern to get the light where we want it.
Now I want to be like Mr. Rogers, and have an operational traffic light hanging on my wall for no reason.
I chuckled a little when I saw that the avatar for this channel is a CFL.
Those circuit boards are beautiful.
That was interesting, thanks for sharing the insides of the traffic light.. Cool..
Can you do a video about the differences between American and European traffic lights. (For Example in Europe traffic lights don't go from Red > Green. Instead they go from Red > Red + Amber > Green.)
Actually that depends on the which European country. E.g. Spain does what you said but not France.
You gotta give us a link to that powerpack (if you'd recommend it)!
It's incredible how big those are when not far away from you.
I was surprised at how many components were on that circuit board. As a regular Big Clive viewer, I expected it to be just a bridge rectifier, a couple of caps, and a transformer.
The LED board itself doesn't have any current limiting so the power board needs to do this.
For what it's worth, I think I actually *preferred* the switch to the camera mic. Your lav mic was sounding awfully rumbly. Perhaps it might benefit from a little highpassing? (Or maybe something something positioning?)
I have a new mic on the way--the one I've been using has been finicky for a while now, and given how the channel is going I ought to be using better equipment. I want to experiment with a tight shotgun mic, too, because I think that might cut down a noise more.
@@TechnologyConnextras I now record 4 channels of audio when filming my own videos, shotgun MKH8060, lav EW G3 w/ ME-2, one mic dedicated to Foley sounds, and a PZM on the table. It gives redundancy, and in post interesting mixes can be had combining the best EQ bands plus accenting the Foley mic or PZM when a particular sound needs emphasizing, like dropping a screw down the hard to get into hole.
I was just thinking you should send it to Big Clive as you said his name.
Love the dodgy 1950s lamp plug!
Love this one take style editing.
Interesting video, I wish not so many companies would keep making the "incandescent look" traffic signal lenses because the light distribution isn't as uniform due to the diffuser and the fresnel lens. I would much rather prefer if they used a design similar to LED COB (chip-on-board) which produces uniform smooth light. It seems like most of the new LED arrows have that smooth appearance where you can't even distinguish the individual LEDs. One minor question, why did you have to tape over the serial number and similar information?? It isn't a sensitive or expensive product like a phone - I just found that odd
I suspect they keep the Fresnel lens and difuser design to keep the dispersion pattern consistent with traditional lights. The required brightness at various angles is most likely codified in law and using the same design as used with incandescent lamps makes it easy to be compliant.
@@alexhajnal107 Yeah that makes sense. Most new LED signal heads don't have any major visible "hotspots" or dim spots. It's only the ones that are either cheaper made or poorly adjusted/installed.
Are you related to the Technology Connections?
Same guy - his second channel, just started!
Woosh...
Don't think so, they look nothing alike
He is his evil twin, the one that likes to destroy tecnology for his own amusement.
No it's a different guy wearing the same jacket
Just discovered this and the other channel. Some notes: LED's are extremely directional compared to incandescent bulbs (a few other comments mentioned this as well). On the power board from what I saw it was pretty standard though the size of it and the fact that it was in a relatively open space likely helps with heat distribution (LED's produce almost no heat but power converters are still relatively inefficient and do produce a lot of heat. A quick explanation of Alternating Current and Direct Current; Alternating current switches polarity which means the positive and negative nodes/wires/sides switch places, this switch occurs frequently (60 times per second or 60 Hertz in the US, 50 in the UK) but gradually (if you look at it with an oscilloscope it's a sin wave with 0 volts in the middle). Direct Current has a fixed positive and negative (on an oscilloscope it's usually a straight line above or below the 0 line unless it's pulsating DC). The basic power converter circuit works by taking an AC input, running it through a transformer (the little copper coil thing) to lower the voltage down (transformers can change the voltage of AC but not DC power and the required voltage for this circuit is relatively small). The reduced AC voltage is then run through a full wave rectifier (4 black diodes) which converts it to pulsating DC (Alternating Current is great for transporting power because of the power of transformers but it can't be used directly in computer electronics or LEDs/pulsating DC means that the power is turning off and on instead of staying on constantly). The rest of the circuit is a voltage regulator and a filter. I'm not really familiar with how most filters actually work since I've only ever built a basic T filter but the basic idea is to smooth out the voltage so it's always on at a fairly constant voltage. The regulator (in this case it appears to be a standard transistor) keeps the voltage from going over a certain value effectively forcing the voltage to remain constant. It is possible that instead of a regular filter this device might actually use pulsating DC but as best I could tell it appeared to be a constant voltage. LED's usually can't take more than a certain voltage (about 5 volts for the ones I used in high school) without burning out but if you use pulsating DC at a high frequency (frequency in this case being how many times per second the current turns off and on) you can use a higher voltage which also increases the brightness of the LEDs. The problem is that it also reduces the life of the LED and the frequency driver (the circuit that creates the desired Pulsating DC power) is a bit of a weak link. The Fresnel lens is more than enough to get the desired brightness while also helping to distribute the light (as mentioned earlier LEDs are highly directional) so it's not really needed here. A frequency driver would also unnecessarily complicate the circuit adding more potential fail points which is exactly what we don't want in a safety light).
Okay, so I feel the need to correct you on many things you mention:
LEDs like these produce TONS of heat. Those are 1 or 3 Watt LED chips. Their efficiency is still rather bad, though green ones are the best ones out there, being the most efficient because of their colour. It are the power converters that have become increasingly efficient in the last 20 years or so and usually outperform the LEDs. 96% efficiency isn't all that strange anymore for a switchmode powersupply, while a LED is way below that number.
In there is a switchmode powersupply, most likely with a constant current output. If this had been a regular iron-core transformer, it would have been significantly bulkier and making the total signal way more heavy.
LEDs don't work on voltage, but have a specified forward voltage at given nominal current THROUGH the LED. Put 'voltage' on a LED (especially 5 Volt, which is far too much for the average LED to handle) and you'll destroy it. This forward voltage can differ greatly from LED to LED and largely depends on the colour: red LEDs have the lowest forward voltage drop, yellow is slightly above, green is even a bit higher and blue (And almost automically, white) LEDs top the chart. On top of that, ever more LEDs consist of multiple LED dies in one housing, increasing the forward voltage for 1 LED-housing to n-amount of LEDs.
LEDs that are driven by PWM at a higher-than-nominal current usually don't encounter a shorter lifespan, but only when driven correctly. Hopefully, the manufacturer has chosen to adhere to the LED-datasheet where it usually states something like: 'Peak rating 1,8 x Inom at 10 % duty-cycle at 5 kHz frequency'. If you stick to those numbers, the LEDs will have a great life expectancy. Go over those numbers and you will shorten their lifespan.
Considering frequency-driving: it's a very common way for almost any LED-driver to drive an LED like that. If not for the current-limiting device that quickly turns the LED on and off at the right times to keep total current in control than just because it's not that necessary to smooth the output. In case of traffic signals however, I consider pulsed DC and PWM circuitry as an absolute no-go: it's not for nothing that some LED-drivers by Recom feature 'Railway approval' (whatever that may mean) as they dim solely by varying the current through the LED, opposed to PWM-dimming most cheap LED-drivers do. You do not want PWM-dimming if you're driving by a signal at 140 km/h: it would be too annoying or even distract too much.
Wow, that was a lot fewer LED's than I was imagining! I got a little nervous when you started working with the innards with your screwdriver while it was still plugged into your power supply, but you seemed to correct that quickly before taking the bits out.
If you asked 100 people how large are traffic lamps. 99+ would say smaller than they are. I remember looking at a fallen pole and being impressed at the size of the thing.
It's a great example of perception vs reality.
Only 8 leds? Wow. White led tech advanced overnight.
The LED signal bulb I have is much thinner than yours and has many more than 8 LEDs on it. I can even see which capacitor blew on it's circuit board should I want to replace it.
JeffFrmJoisey if a capacitor resistor mosfet or anything else on a PCB board blows there is a reason why it blew so more than likely if you replaced the part it will just blow up again. You have an older type of LED module the new ones have a more full ball such as the one in this video. Who is the manufacturer of your LED module? The most common manufacturer and well-known manufacturer for traffic signal equipment such as led modules these days is Dialight manufacturers that are less used these days in my area anyway is Leo Tech and GE it really depends on what your area prefers.
LED modules tend to get warm even when running here in Florida not Hot, more than likely it blew because it got warm however I have seen LED modules blow the cap from a surge such as lightning before it blows a loadswitch than the load switch blows. LED modules are a disposable item it's not worth trying to fix especially since its an older one some of the LEDs are sure to be burnt out. I have never seen a cap in the field blow because it got warm usually they blow because of a surge or a short somewhere.
Cool to see what's inside! I'm a bit disappointed we didn't get to see it with the magnifying lens removed but the diffusing one in place just for fun, but still cool!
This was fun and informative! I'm glad to be part of the shared experience. I guess I should be thanking TH-cam but we already know that part. Content creators such as yourself are the reason TH-cam remains interesting for smarty pants people.
That beer can shaped battery pack inverter thing is noisy but cool. How long does it last before needing to be recharged?
Ha!! that question is functionally similar to "how long does a REAL beer can last before it's empty??"
Gordo Depends on how thirsty you are.
QED ;-)
That looks like a small switching power supply. Probably is. They're reliable, safe, and hard to damage, most power transients and overloads that would cause problems cause them to 'fold back' and effectively switch off until power is removed and restored.
Power usage is probably related to human factors; The human eye is most sensitive to Green, followed by blue, then red. Most people are not nearly as sensitive to yellow light (some people have a 4th set of cones for yellow, btw, which is neat). Also, yellow blends in much stronger with daylight. Find a good time (when it's not backlit or front lit) and an old still incandescent set. You'll notice the yellow isn't as 'strong' looking as red or green if everything is clean.
There is likely the LED efficiency on different wavelengths on top of what you mentioned.
Just like the blue LED's seems take designers by suprise, since I have rarely seen those dim.
(while they often keep other ones at sane levels)
COngratulations for your new chanel man! I liked the first one very much :) Good luck with this one too :D
Here in Australia, there's a sort of quirk in the law where it is *technically* illegal to replace a 240v light bulb, because, in a way, you are manipulating electrical systems, or something to that effect. So traffic lights here have a clever little workaround, so that you don't need to be an electrician (or 'sparky' here) to replace the bulbs. What they do, is they feed 240v to the light bulb box, but behind each light, there is a stepdown, likely isolation, transformer, that turns 240v into 10v, IIRC. So the lights here are all 10VAC, and to that end, I guess that LED retrofits may leave this transformer in place, but have interesting power supplies that would convert 10V into whatever DC the LEDs need.
Also, I live in Queensland, but traffic lights in New South Wales and Victoria are *mostly* the same. So I was taken aback when I noticed the LEDs in Tasmania (of which there are very few, most are still incandescent!) looked markedly different. It took a solid couple of days to figure out, and a lot of distracted driving gawking at the goddamn traffic lights, but what they'd done In Van Diemens Land, is they don't use the fresnel lenses. Now the fresnel lenses here along the east coast, aren't to the extent in the states where they mimic incandescent bulbs. You will still readily see each LED, but the lenses are a lot less... aggressive, for want of a better word. The lenses they have, only just diffuse the light a little bit, and spread it out more.
So yeah, that's a bit of traffic light trivia that no one will care about, and that Mr Technology Connections will probably not see!
still wanna see what is inside the red one
I'm the guy that changes these things out.
I used to be the guy that changes these out in Phoenix. Now retired
It was cool that you mentioned Big Clive because I was thinking that it would be cool to see his perspective on it.
I've taken quite a few of those GE Traffic Signal inserts apart. I'm glad you did not cut it open. They have a power supply with a output of 24VDC. The power supply can be repurposed into other electronic projects or used to repair other lights.
The screw that holds the wire cover has kind of a dual function. it not only hold on the cover but when assembling the light it allows the air trapped inside to escape. Also I have found some that where full of water from being stored improperly so the seal is not 100%.
I would be surprised if the power supply is a constant voltage one: I expect a constant current device given that those are the most efficient.
In my opinion, sealed cabinets of whatever kind of form are bad: they should never be fully sealed but need a small hole to allow air (and most importantly) water or accumulated condensation, to escape. Sealing a unit is asking for trouble. As the PCB does not seems to be coated, sealing is an even worse choice.
Do more stuff like this.