I bought these as a convenient source of long parallel arrays of LEDs suitable for hacking into outdoor solar lights. I was expecting it to be just a USB plug, resistor and the parallel string of lights, but it turned out quite intriguing.
Firstly, the current was higher than expected at 800mA (8mA per LED) and there's no resistor!
Further investigation found that three wires were used along the run so that the positive side of the array was fed from one end and the negative side of the array was fed from the other end. This has two functions. The combined resistance of the feed and return wire to the far end acts as the resistance, and this arrangement results in even brightness along the full string instead of being brightest at one end and tapering off along the string due to the increasing resistance and voltage drop.
Firstly, the current was higher than expected at 800mA (8mA per LED) and there's no resistor!
Further investigation found that three wires were used along the run so that the positive side of the array was fed from one end and the negative side of the array was fed from the other end. This has two functions. The combined resistance of the feed and return wire to the far end acts as the resistance, and this arrangement results in even brightness along the full string instead of being brightest at one end and tapering off along the string due to the increasing resistance and voltage drop.
I brought the same string lights Of 10M and i wat to use it as usb power string lights how to do it
Fancy these for my mini office station at home.
I built the station some 15 years ago but had not seen the LEDs I was looking for to finish the lighting.
Found them!
Thanks Clive.
I rewatched this a dozen time, and you definitely did not explain well what that 3rd wire is doing. I don't get it. Would love to get it, but I don't.
I have four separate solar powered 5m copper wire led strings. They are all failing. Can I cut the strings from their solar box panels and power the loose strings using a central alternative power source e.g. A/C. What would you recommend so that I don't have to depend on failing solar batteries every now and then.
but all leds get higher current than that of 2.5 ohms.
I purchased some copper wired micro fairy lights wired to 3 x 1.5 batteries, I wanted to use them with a usb lead so I soldered the black and the red wires of the usb to the micro lights, plugged them in to my usb plug and found they were getting very hot. Then they all blew one by one what can I do please,
Can you connect a 200 light set of solar fairy lights to a 200 set of fairy lights that you plug in? I found your video fascinating. But I'm 66. I don't remember much electrical theory from my junior year of physics. Thank you.
Would a multi-function controller version of these be 3 true wires then or is there cleverness for making these do pwm in some fashion?
Hello, I have solar multicolor(blue,green,red, warm) fairy lights and it also have 3 wires too, I want to convert it into usb, when I try to connect the two wires of fairy lights the blue and green only shines so I try to connect the 3rd wire but the red and warm only shine. What should I do? I'm confused…….
I'm wanting to take my battery charged string and attach them to my plug in one. Guess I learned something else instead
At least i wont blow my powerbank from the currect that these fairy lights make.
Can you please try a cheap 26cm ring light as it does not indicate the current it consumes and how many watts it is… I have a 26cm ring light that blew the ic chip on my powerbank
I have 1 meters wire led string, and tested to modified for portable led, and i put on the battery 2000mah And finally it's broken, it doesn't work
I have a 10 meter one of this string light. I can't find a longer one in our online store. Will it be alright to connect a 10 meter and 5 meter one together?
I bought 100 bulbs usb leds copper one, it was fine, then i accidentally cut it into half,
The one half with usb plug is only lighting other half totally inoperable , since its pure copper string not a regular wire , even if i tried to connect it, but couldn't attach the broken half portion of led string.
Need ur help
I have some and only every other one works. When I change polarity the ones that weren’t lit up before are now lit up, but again every other one. Does anyone have any ideas?
Brilliant…thanks !!!!