I want to repair an LED Christmas light string with 3 wires per bulb ...
It's interesting- pairs of LED's are in parallel and these pairs are wired in series. The string uses a full-wave rectifier (improves flicker) and splits the diodes between the plug end and receptacle end (so both plug and receptacle are not too large).
diodes - How are these LED Christmas lights wired? - Electrical ...
2023年12月8日 · Ours have a rectifier first in line at the plug, then 25 led, another rectifier and another 25 led... Between the last of the 25 led and the next rectifier there are only 2 wires, they are the hot and neutral. The rest of the wiring consists of 3 wires, the 120 volt feed to the next rectifier, the power from the last rectifier and a neutral.
Why is there no resistor in a christmas LED string light?
2019年1月2日 · I tried to fix same LED Christmas's light. It has resistor and diode inside. One string 50 LEDs divide to two parts. 25 LED bulbs connected in series and one diode and resistor. Measuring current gave half sine wave, amplitude 60 mA. So the average is 20 mA. Smart inventors just replaced incandescent bulb with LED and added diode and resistor.
led - Can I shorten a length of C9 Christmas lights? - Electrical ...
If you know (or can measure) the LED current for each LED (end therefore for a series) and the voltage drop of each and the applied voltage, you could calculate the resistance and wattage of a resistor to limit the current to a safe value. $$ R = { V_{supply} - n V_{LED} \over I_{LED} } $$ $$ P = {I_{LED}}^2 R $$
led strip - Circuit diagrams for LED Chaser Christmas Lights ...
I'm looking for circuit diagramS for ~50 LED strip with lights running* repeatedly from the bottom to the top of the Christmas tree. I found simple solutions with only 13-15 LEDs, but this is, obviously, not enough for a big Christmas tree. The circuit must be DC driven. Thanks.
Fairy Lights Wiring - Electrical Engineering Stack Exchange
Note I have tried wiring 2 strings to 2 AAs and the brightness was not there. Not to mention having to carry around 32 AAs would be a bit tedious. Attached is an image of how I wired it up in series and parallel. Series wiring - LEDs would not light up. Parallel wiring - LEDs would light up however the battery slowly started getting hotter and ...
led - How to find a faulty bulb in a Christmas lights string ...
2011年12月17日 · The signal is amplified using a BJT to make sound on a piezoelectric speaker. If a light is burned out it the E-field will exist on the wire going into the light, but, not on its exit wire. Using this principal it is easy to locate the burned light. He applies this to incandescent light string, but, the same principal would apply to an LED string.
Flashing LED String/Christmas lights to steady on [closed]
2021年12月14日 · Bypassing a multi function Christmas light string controller My string lights is of 300 LEDs, input 220-240 volts. I have tried putting the wires directly on the rectifier on another EK-04 (slightly different circuit) LED 120 bulbs 220-240volt but it just makes their resistors very hot. Just want it to stay on without heating.
Can I add to the wire length of C9 LED Christmas Lights? - wiring
2016年11月28日 · I've found plenty on the topic of shortening C9 LED Christmas Lights, but have not found anything about lengthening a string. I don't want to add any additional bulbs, but rather add some additional wire to transition between areas that I don't want lights (between windows, gutter/facia transitions, etc.).
voltage - How do I use a 12V LED indicator light for an alternator
2021年7月9日 · I have a dune buggy project and wanted to use a small LED indicator lamp in the charging system. The way it works is, key on, lamp illuminates. Engine starts, power to alternator field, lamp goes out. My issue is the power coming out of the LED light to the field on the alternator is barely 2 volts. Not enough to energize the field.