While testing some newly acquired warm white 12V LED tape (5050 and 3528) I noticed that the current for the whole 5m length did not tally with the expected current based on the type of LED and value of the series resistor.
This appears to be down to a modest voltage drop along the run that results in the LEDs at the far end getting a lot less current than the ones at the power supply connection point. It's not a high voltage drop, but because the LEDs tend to have a fairly narrow forward voltage range, most of the difference occurs across the resistors, and even half a volt makes a huge difference to the current for a given resistor value.
It follows that it's better to use short lengths of this tape, and if you are needing a long run then divide it down into shorter individually fed sections.
This appears to be down to a modest voltage drop along the run that results in the LEDs at the far end getting a lot less current than the ones at the power supply connection point. It's not a high voltage drop, but because the LEDs tend to have a fairly narrow forward voltage range, most of the difference occurs across the resistors, and even half a volt makes a huge difference to the current for a given resistor value.
It follows that it's better to use short lengths of this tape, and if you are needing a long run then divide it down into shorter individually fed sections.
Clive, I know this is an old video but it is still absolutely useful. I’m making some rectangular LED panels from a dozen or more shorter lengths on aluminium plate. Connecting them in series seems slightly less daunting for mediocre solderists. But you’ve convinced me to push ahead with attempting parallel power. Tutorials suggest via thick copper cables running the length of each side and tacking each end, or just bare copper wire in a wiggle formation, or “shunt” injection wiring. Still haven’t decided which method to attempt but I will avoid just putting them together in series.
Hey thanks for this, I am wiring up a vehicle with vanity lights and your research just allowed me to vastly improve the output of my system, thank you!
Great timing in finding this baby as I want to buy some! Cheers Clive
Hello Clive love watching your videos 😁 just a quick question, I’m planing on using these lights on my model railway which I’m going to be cutting them down into their banks of 3 so I get 100 sections and with wire to drop through the baseboard. I am planning on having the terminal blocks which you use fork connectors on for the connections which then each individual of 12 connector block will run back too the power supply which is a regulated power supply the ones which you can select what voltage you require which they are normally 1000milliamps so with the tape you shown at 16 milliamperes I worked out it’s around 64 per plug however I will only put 50 on per plug as not to tax it would this be fine. Any help would be appreciated many thanks Christian
My kit came with amplifiers and a larger power supply.
Why not just run 24volts to them?
Would feeding voltage from both ends of the tape help with the voltage drops?
I have 3 ten foot strips on the 3 rd strip the light is barely visible but it is very bright on first strip any ideas ??
Power injection. Power both ends.
The adhesive tape they use is not fit for purpose.
I purchased some Phillips branded LED tape lights that were able to produce all colors + white, select-able from the IR remote. The majority of that I find on EBAY is only "RGB" with no white capability. What do I serach for that will give me RGB+white on the same tape light strip?
Even more fun when you're wiring up WS2812B addressable LED strips that run on 5 volts so twice the current.
I've just bought two strips for my disco room to add to the two I already have …
(Some people would call it "home theatre" , but I find abstract light patterns more entertaining most of the time)
So I have invested in good quality power cables and will power the strips from both ends.
Coincidentally I want the lights to start from the extremities, so bought a reel of 0.75mm twin mains just for the data lines.
I have three cellars, and use 2 metre lengths for each for lighting, works pretty well.
Did you say 16 or 60 mA?!
How many watts on average would a 5m strip of 300 3528 LEDs draw? Because I fear they are overloading a 65 watt laptop power supply.
Mine is supposedly a cheap smd 5050 rgb 12V 60leds/meter. Selecting full white, the voltage is measured. I am powering the full 5 meter rgb roll without any cuts in the middle. Just before the first led the voltage is 12V for R G and B. But at after the last led which is after 5 meter the voltage drops to 8.5V for every channel; concluding it as a cheap strip. I then inject at the end of the strip with the 4-core cable that comes from controller which is the same that is injected at the start end of the strip. The result is now the end strip is as bright as the the start strip. But the mid strip is not as bright, the voltage is 10V. I then again inject in the middle and now every section looks similarly bright. Now I wonder, is this bad practice? Will the wattage go over the spec which is 14,4watt/meter or 72 watt for that one 5-meter roll rgb strip? I guess no. Please help clarify this folks. Thanks