electrical question here! led lights.

[zheka757]

Im trying to repair my old led lights and they have some burned out led chips and melted resistors. they say that resistors are color coded. do any of you know what resistor is this? the leds are 3w led chip, its a 4 channel lights with total of 48 leds, and this is one out of four modules.

trying to post some pictures, not letting me
why when i click on adding attachments nothing happens?

 

[Sk8r]

Try images via Imgur. That works for some.

 

[Alex114]

Yes resistors are color coded. They are fairly easy to read once you know how. Can you see all of the colors and how many color bands there are and where the gap between them is? If you tell me I can tell you what the resistor reading is

 

[zheka757]

they are super small like 1/4'' lenth and i only see 2 collors on it half of it is blue and half of it is red. and took one off and it measures 129 ohm. But i question my multi meter for accuracy also!

let me work on getting the picture for you
https://imgur.com/a/upKHsnI


i hope this picture post works, thanks sk8r

 

[zheka757]

got a new meter and retested one of the resistors, and it showed 4.6M ohms. also its only measures one way on resistor. and i thought resistors are not directional component, and can be measured both ways.

 

[Alex114]

Dang I've never seen a resistor like that. Can you contact the manufacturer to ask? And 4.6M seems a little large but not unreasonable. And yes resistors should be non directional. My guess is the multimeter might only read one way or you couldn't get good contact when measuring across the one side.

 

[zheka757]

so contact manufacture, and of course they not telling me what resistors they use in them. but i think its because of resistors my led chips burn out so often. or what ever problem is elsewhere that burns resistors out also. and i mesure my resistor, most of them resumes 4.6m and some measures like 3 owns some nothing at all.

but they also tells me that its ok to not use resistor in there also. Im so confused now.

 

[blowmecius]

They are not resistors. They are diodes, probably zener diodes. See if there is a part number printed on the case. If not read this thread it explains how to determine the correct one:
https://www.reefcentral.com/forums/showthread.php?t=2700218&highlight=Resistor

 

[zheka757]

WOW man thank you! I had no idea it was diode. i thought the whole time it was resistor. so i talk to them in china again, who makes it, because im trying to understand why my leds burn out prematurely. they cant answer that. however they did say its a diode 5.1 volt and its 1w, but you can also use 3w. i wonder if becouse they use 1w diode on a 3w led chip, if that the reason they burn out prematurely.

 

[blowmecius]

I am not familiar with this particular circuit design but I will assume that the diode in intended to protect the led from curent spikes. A zener diode will blow from overcurrent so using a higher rated one might help. I suspect their design lacks sufficient surge protection. I suggest using a surge protector. I use these for my aquariums:

https://www.amazon.com/dp/B07D6QD9NF/ref=twister_B08CBR5W7Q?_encoding=UTF8&psc=1

 

[zheka757]

I am not familiar with this particular circuit design but I will assume that the diode in intended to protect the led from curent spikes. A zener diode will blow from overcurrent so using a higher rated one might help. I suspect their design lacks sufficient surge protection. I suggest using a surge protector. I use these for my aquariums:

https://www.amazon.com/dp/B07D6QD9NF/ref=twister_B08CBR5W7Q?_encoding=UTF8&psc=1

just looked at my power strip, and it did had surge protection on it.

 

[zheka757]

So figured out that those are a 5.1v .5w diodes. Ordering 5.1v 1w diodes and will see if that can do a better job at not burning my LEDs prematurely.