LEDgardener

Going for a much higher power output single COB system.

Trying to use a Citizen CLU058-3618C4 I thought I had selected the correct driver to run the COB as powerful as possible limited to the drivers on the market. With a Meanwell HLG-480H-C3500B. But in assembling all the components I find I miscalculated somewhere I assume, becaus its not working as flawlessly as my 320w's

Citizen CLU058-3618
Voltage [typical] 102.1

Absolute Maximum Ratings
Input Power(W): 524.6w
Forward Current (mA): 4140

HLG-480H-C3500B

Output:
Rated current:3500mA
Constant Current region: 68-137w
Open Circuit max: 170v

where did I got wrong? what do I misunderstand

Everything appears right to me. At 3500mA, that COB should have a forward voltage of ~111V, depending on temperature (if anything, it'd be lower). Do you have enough room on your AC circuit for this driver?

What are the symptoms, exactly?

Man, you're working with some cool gear.

30amp 240v circuit for things. They do have a very strong in rush load, but still not too much.

Symptoms are nothing happening when I plug it in/turn it on.

Local electronics shop tested my driver and confirmed it was outputting correctly. I even purchased a new (I'm going to build more anyway) COB in case I got a dud from the factory, tried with a new one and still nothing.

I went back and rechecked my connections in case I had something funny that I missed and everything looked fine.

I tried to double check against the Driver calculator spreadsheet that you built, but when I select for Citizen CLU058 it doesn't show any compatible drivers? Am I looking at it incorrectly, or is it "broken somehow?

Have you verified your holders are making good contact with the pads on the COB? Have you tried different drivers on the COBs?

I checked the calculator for the CLU058 and it seems to be working properly for me. Maybe your quantity was too high?

I get conductivity everywhere but across the LED. Even when I use the ohm-meter on the COB itself?

Is there any specific way to use a tester on a COB? I'm lost when it come to those things :/

How could I check? Its the specific brand [BJB?] to hold the CITIZEN COB, and the Heatsink is the proper pattern specific for Citizen. There isn't really any way to see the contacts once you screw it down.

I though of that as a possibility, but all the components are from the same "eco-system" and should in theory be designed to work together. I'd hate to have to solder the damn thing because it looks so clean and perfect as-is.

I would try to find a way to test it without the holder... It'll be difficult to do safely though. Might have to solder temporarily.

Well shit, one step forward and two steps back...

Turns out that BJB holder is super finicky and the COB contact pads are freaking tiny. After like 6 tries thinking I had it lined up, I finally got things in the right spot and she turned on... for 10 glorious seconds or so. Then the magic smoke got out....

So I assumed the TIM (THERMAL INTERFACE MATERIAL) that cdiweb sells is a more convenient alternative to thermal paste. Is that shit any good? When removing the bubbly COB I notice that the TIM looks untouched. Am I wrong to assume that it should have melted as part of its function? Are these mounts/holders garbage as it comes to applying enough pressure for the heatsink to do it's job? Did I do my math wrong and over driven the COB or was this just a thermal issue?

Dammit, I just melted $50.

Noooooooo!

Your math is good on the current so I think this will come down to an issue with the other variables you listed (pressure, TIM). Can you link to the TIM you used?

That being said, that is still a whole lot of power running through that one COB, plus if you don't have a potentiometer on your driver and the dimming leads are just open, you might have a little more than 3,500mA as well.

Next attempt, I'd try a name brand thermal interface like Arctic Silver or similar, and I'd either skip the holder and just screw the COB straight down and solder, or I'd torque the hell out of the screws on the BJB and make sure it's as tight as it'll get. Start with the driver dimmed and slowly raise current and monitor temp.

At least we got the first problem figured though

https://www.cdiweb.com/ProductDetail/G1 ... ch/594265/

I think that was the same one.

Just trying to be "cleaner" and more professional then a big glob of Arctic Silver..

Max current is like 4400mA so I figured there would still be PLENTY of headroom.

It might have been premature but I went ahead and ordered 2 more drivers identical to the ones I have in service currently. So I can always run these stable but at a lower power. Either way I plan on building 10-12 of these for my personal use, and I have a TON of associates that want me to build some for them as well.

How do these drivers go about regulating their voltage? It's a "constant current," driver. But technically it's voltage can surpass the max voltage of the chip. Could you help me understand how it regulates it's voltage?