Part of me loves these strings of lights because they are cheap and cheerful, but part of me also knows that quite a few people have probably been given an unforgettable electrical festive experience from handling them while powered.
Here's an autopsy on some 100, 200 and 500 LED sets with some data about the series LED multiples and resistors used in line.
Then I decided to hack some into one of the little capacitive dropper modules to take the strain off the resistors, and the results were very good. But still a bit of a shock hazard. So only for flame retarded rubber Xmas trees mounted on the ceiling.
It's notable that a thermal scan of the 500 LED set once I'd wired them into the capacitive dropper, showed such a low resistor temperature that they didn't even show a different colour from the rest of the LED assembly.
Here's an autopsy on some 100, 200 and 500 LED sets with some data about the series LED multiples and resistors used in line.
Then I decided to hack some into one of the little capacitive dropper modules to take the strain off the resistors, and the results were very good. But still a bit of a shock hazard. So only for flame retarded rubber Xmas trees mounted on the ceiling.
It's notable that a thermal scan of the 500 LED set once I'd wired them into the capacitive dropper, showed such a low resistor temperature that they didn't even show a different colour from the rest of the LED assembly.
Can you put a full bridge rectifier inline on the positive and run the lights normally with no flashing?
Nope, no flickering in that last set.
Why do some strings not have any resistors?
Interesting, i picked up some of these types of LED's,they look the same anyway but are powered by 2xaa batteries a string of 48 of them from the dollar store. Last season I hacked in a usb cabe to it giving it 4.5v. I wasnt concerned if they'd burn out and they did, but not like how this video describes and only a couple did while the others worked fine still, no melting fortunately and they were being over volted, it was so bright it was amazing actually, I thought about adding a proper power supply of some kind to not give them so much but im an electronics noob and its good to hear theyre not very heat tolerant so i'll be more careful.
I also picked up some of those bead (blob) LEDs here from the dollar store, ones that look like they're attached to bare wire, a string of 60 powered by 3xaaa batteries I thught would be good for a usb powered mod and id imagine are more heat tolerant? They seem to perform better then the types of LEDs shown here anyhow, they're just stay brighter for longer it seems on the batteries. Anyway glad i found this channel and video, the info here is very valuable and could save lives, thank you.
I don't know why they bother making those electrode boilers when you can just chuck one of these in there. Probably safer, discounting the decomposing plastic.
Smokin? Like the "12V" ones I got that changed color slightly and that hit 300F in under a minute off 12 volts?…guessing they were supposed to be 5V
Rubber/asbestos (Christmas) trees? – No way. They just sling 'em up outside and it gets quite exciting when it rains. We had a game – guess which set will still be working the next day and which tree would have the biggest skid mark….
My uncle wanted me to check a set of Christmas lights once, and I found it was some cheap Chinese set he found online. There was no strain relief, one of the main wires had pulled loose from the board. They weren't thick-enough wires, either. I refused to fix them and told him to throw them out. He's always looking for a deal, but I don't think burning his house down or getting shocked should be the result.
I have 6 of those light strings in my tree , one on my furniture and one at my window , working around 7 hours per day
Am i gonna di e
Good job Clive. Lights are running much cooler and are now much safer. I can't believe they sell them like that on eBay!
EBay should put " Lights May start smoking & Poppin 3 days later. Buy at your own risk!" Lol
These things are extremely poorly made. The cover on the set I got from A***S wasn't even attached … the hot-melt 'dollop' had failed, and the soldered connections from the lamp strings were absolutely horrendous with stray strands and dry joints. Avoid like the plague.
Enjoyed you video, very educational for newb fools like me. My version of these keep cutting out after about 12 hours, like there on a thermal fuse or something. Is this possible? I want to put them on a timer anyway, so would like to cure the automatic cutoff – any ideas?