Kessil

Fixing LED fixture

I have these couple fixtures that do not work properly; at first I was thinking make a functional one from two partially working fixtures. The power supplies, drivers? all work; tested the working block of LED's on each of the power supplies and all six drivers work. Got a watch battery and rigged it with a wire to test each LED on one fixture; three do not work on the blocks that don't power any of the LED's; my question is, if I replace those faulty LED's, Is the problem supposed to be fixed? I thought if one LED was out, the rest should have no issue turning on unless they are set like an old Christmas light; one tiny bulb goes out then the entire light set is at fault.
The burnt looking LED's are UV but they do work.

Thanks

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It's depends on how it's wired. In series or parallel.uf it's series the circuit is broken so one led out whole thing is out.


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IIRC LEDs can burn out either open or closed circuit, so it may infact not move power through circuit.

That said UV leds are notorious burning the optics on them
 
So in theory and if the LED's are wired in series, a replacement would be the ideal thing but I could also test the bank of non-working LED's with a jumper at the faulty LED?

I'm tempted on replacing the UV's with either blue or if I can get the same/similar type of diodes from ebay in red and green might as well...
One of those rainy days things...
 
Jumper would work as long as there is a good driver that can regulate the voltage. Also dont do like me and turn the driver on then attach to test, sure fire way to burn out a string if leds
 
It's a Chinese Black Box; believe it to be a BoostLED; the power supplies are more of an AC to DC adapter than a proper LED Driver
 
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Yup, they are wired in series, just soldered a jumper on a faulty one and power is back on.
Now to find replacement LED's; have some spare Cree stars but I don't think they will just "slide" in
 
Let me guess, you scored 2 that work and 2 that 1/2 work?

Two; one, 1/3rd works and one that 2/3rds work; I was thinking of de-solder LED's from one to fix the other or use the drivers if they were the faulty ones.
Two do work but at first I thought the UV's were dead since they show burnt optics but I guess that's what happens with UV light.
I don't know if I should add other color LED's as to have a full spectrum; those particular diodes are available in multiple colors, tempting...
 
Now that the bug bit, among those things to play with, I found a Potentiometer; Can I wire it to dim the fixtures?
The drivers are full blast, I wonder if I can add the potentiometer on the DC side of the power supply/driver?
I was given some LED drivers but they are non-dimmable, some heat sinks, optics and a few Cree stars in white and blue.

I also found time to fix a DIY ATO unit that was heck-o-ugly, now is just ugly. This thing has been in a box at least 10 years !!!
 
Now that the bug bit, among those things to play with, I found a Potentiometer; Can I wire it to dim the fixtures?
The drivers are full blast, I wonder if I can add the potentiometer on the DC side of the power supply/driver?
I was given some LED drivers but they are non-dimmable, some heat sinks, optics and a few Cree stars in white and blue.

I also found time to fix a DIY ATO unit that was heck-o-ugly, now is just ugly. This thing has been in a box at least 10 years !!!

Kind of, but not recommended.
The drivers are current drivers, meaning they maintain a fixed current, by changing voltage to LED.
Dropping the input voltage with potentiometer will do nothing at first, until you hit the sum of the Vf of the LEDs in a series string.
At that point, they will start to dim. (Assuming buck not boost drivers)
But they will not be even, since Vf can vary for each diode.
That is also a lot of power to send through the potentiometer. It would need a heat sink.
 
Gotcha; I'll be on the look for a Meanwell driver or two but this is one of those spare time projects.
This is a 120W fixture 1W diodes; Do you think the power supply picture is a driver? to me looks like a AC/DC transformer.
 
This is one of those fix it because seems interesting things in life. I honestly thought the drivers were faulty and I have a couple non-dim drivers that a nice guy on RC was giving away in the SJ area, he even sent them to SF with a friend.
I have al old, old Current USA Sunpod, 70W MH that I want to gut and install the LED's he kindly gave me then yesterday while looking for a ballast for a person in San Diego, came across a C-USA Sundial 150W MH, 2x36W PC,s !!
 
How many channels is that thing? A good, in expensive, option would be to get some Meanwell LDD drivers, want to say you can connect up to 15 LEDs per driver, then just use a separate power supply to power everything. And if you want to get really spanky you can throw in any number of PWM dimming solutions for the Meanwells, everything can be done after the fact too. Of course if there are simply 2 super long strings of LEDs it would be more work than it's worth probably... hell Chinese blackbox fixture almost by default is more work than it's worth :D
 
Fixture has three channels, two daylight/blue and blue/uv
About the "...more work than it's worth" yeah, it has over 100 small screws that attach the PCB to the heat-sink and all of them have to come off in order to replace a faulty LED then all of them have to screwed back on to make sure heat is transferred properly. I did use some thermal compound; that stuff is messy...
So I read somewhere that the old Neptune AquaSurf can be used for dimming lights?; I mean, makes sense; the purpose of that unit is to control DC power-heads which is basically ramping up and down the power AKA dimmer.
As fallen from the sky, in my leisure time of yesterday, found a donated Odyssea LED fixture (Please don't lecture me, I know I'm a hoarder but with a purpose) from one of the guys on RC; not all LED's worked so scalpel, welding iron and voila! those LED's are of the same size (not sure of power but what the heck) already weld them onto the fixture and it's alive' IT'S ALIVE !!
The carcass goes to the recycling bin but is a nice aluminum casing so might as well go back, all the way back in the basement...

You’re s gem Mario. Never stop!

Thank you Sir, coming from you is a compliment.
 
Yes, that looks like a power supply in the picture, not a driver, but could be both.

Unlikely, but there may not even be a driver.
Some really cheap boards just use a resistor.
(Measure Vf on diodes, calculate current-voltage, add big resistor to match)
A bit of extra labor, but if labor is cheap, it is less than a driver.

If you are going to put your own driver on, you need to understand the current circuit first.
Supply voltage, current per string, total Vf, Source or Drain connected, and so on.
 
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