Did I overheat my QB? Broken QB

dendroaspis · Apr 13, 2020

I have a question can anyone identify the problem on this QB? Its a kingbrite, i cut it up into three pieces too fit the tent, but upon inspecting it I noticed some weird markings next to some LED’s. Did they overheat? They have been running for almost a year.

dendroaspis · Apr 13, 2020

Or did this maybe happen because of the way they are set-up? I forgot if these are connect in series, or not?

Barristan Whitebeard · Apr 13, 2020

dendroaspis said:
I have a question can anyone identify the problem on this QB? Its a kingbrite, i cut it up into three pieces too fit the tent, but upon inspecting it I noticed some weird markings next to some LED’s. Did they overheat? They have been running for almost a year.
View attachment 4532506
View attachment 4532509
View attachment 4532512

Is the top photo current, and the middle photo when the kit was new?

What is the exact model of driver that is powering the light?

Budzbuddha · Apr 13, 2020

You mentioned kingbrite , there you go.

dendroaspis · Apr 13, 2020

Barristan Whitebeard said:
Is the top photo current, and the middle photo when the kit was new?

What is the exact model of driver that is powering the light?

they are both current.. one is dimmed the other is max power. At max power there is still a difference in intensity.
The driver is the meanwell hlg-320h-48b.

About my comment on in series. I can remember vaguely that either parrelel or series could cause trouble with leds. Is that maybe what happened here? Ita been a year since I dove into that material.

Boatguy · Apr 13, 2020

dendroaspis said:
they are both current.. one is dimmed the other is max power. At max power there is still a difference in intensity.
The driver is the meanwell hlg-320h-48b.

About my comment on in series. I can remember vaguely that either parrelel or series could cause trouble with leds. Is that maybe what happened here? Ita been a year since I dove into that material.

It is a board, so it is prewired with a combination of series and parallel. Looks like something went wrong and now they are toast

dendroaspis · Apr 13, 2020

Boatguy said:
It is a board, so it is prewired with a combination of series and parallel. Looks like something went wrong and now they are toast

Thanks, as far as I can remember I followed the instructions. Well sucks to be me right now I guess.

So far kingbrite has always replaced broken parts, lets see how they handle this.

dendroaspis · Apr 13, 2020

Budzbuddha said:
You mentioned kingbrite , there you go.

I’ve orderderd a couple of times from them. In total me and my friend own 6qb’s and they work fine. Except this one. I’ve found their customer support to be superb aswell.

dendroaspis · Apr 13, 2020

Boatguy said:
It is a board, so it is prewired with a combination of series and parallel. Looks like something went wrong and now they are toast

I see, I think this board wired differently with this driver compared to my other QB’s. Maybe they are not suited for that. I’ll dive into that tomorrow.

Boatguy · Apr 13, 2020

dendroaspis said:
I see, I think this board wired differently with this driver compared to my other QB’s. Maybe they are not suited for that. I’ll dive into that tomorrow.

There isnt a whole lot you can do to fix it. You should probably start shopping

dendroaspis · Apr 13, 2020

Boatguy said:
There isnt a whole lot you can do to fix it. You should probably start shopping

Jup, i guess so, though I’d like to understand fully why they are toast. So that if I’m to blaim, it wont happen again. I’m vegging for now. So i’ve got some time on my hands.

GBAUTO · Apr 13, 2020

dendroaspis said:
they are both current.. one is dimmed the other is max power. At max power there is still a difference in intensity.
The driver is the meanwell hlg-320h-48b.

About my comment on in series. I can remember vaguely that either parrelel or series could cause trouble with leds. Is that maybe what happened here? Ita been a year since I dove into that material.

That driver needs the boards wired in parallel. The + & - terminals of each board should be connected to the + &- output leads of the driver.

Moabfighter · Apr 13, 2020

dendroaspis said:
Jup, i guess so, though I’d like to understand fully why they are toast. So that if I’m to blaim, it wont happen again. I’m vegging for now. So i’ve got some time on my hands.

Call HLG and thank me later.

dendroaspis · Apr 14, 2020

GBAUTO said:
That driver needs the boards wired in parallel. The + & - terminals of each board should be connected to the + &- output leads of the driver.

Thanks, just woke up and was about dive into that now I already have the answer. They are wired in parallel. So that shouldnt have been the problem.

Rocket Soul · Apr 14, 2020

You have some dead diodes but all led strings seems intact. This means:
Strings inside the board have different voltage so the current gets distributed differently between strings. As you see, on the first min dim photo: the strings with more broken diodes are brighter. Maybe theres one or two

When you have current higher this is less apparent. Ask for warranty service and run your boards a little softer in the future.

dendroaspis · Apr 14, 2020

Rocket Soul said:
You have some dead diodes but all led strings seems intact. This means:
Strings inside the board have different voltage so the current gets distributed differently between strings. As you see, on the first min dim photo: the strings with more broken diodes are brighter. Maybe theres one or two

When you have current higher this is less apparent. Ask for warranty service and run your boards a little softer in the future.

Thank you. That is very helpfull info. I will email kingbrite tomorrow, I’m redoing my entire setup today. I’ll let you know what kingbrite says about this. Since some people seem to be hating on them, I’ll post it here.

dendroaspis · Apr 18, 2020

Okay, a little update. I went over to my friend who also has a medical license to grow for her MS. She has three kingbright boards. And what do you know. The V2 versions both are toast aswell.. I went to check them because of what happend to to mine. Now I have one V2 board that works. And the the two V3 (with added 660 nm epistr diodes) boards we own are still runing strongly. So maybe, this is an issue with their earlier boards. I’m now contemplating buying HGL boards and swapping them to this heatsink/driver set-up.

dendroaspis · Apr 18, 2020

Is there a topic where I can share this info? Is that the “chinese quatum boards knock off builds” topic where this info is relevant?

coreywebster · Apr 18, 2020

dendroaspis said:
Is there a topic where I can share this info? Is that the “chinese quatum boards knock off builds” topic where this info is relevant?

Yeah, that would be the correct place.

Rocket Soul · Apr 18, 2020

Weve seen "batches" of dodgy quality occasionally even from kb/meijiu on some. Warranty given has been erratic: some got new gear or money back some got nothing for litterally the same problems. Personally i dont feel like the china boards should not be run like hlg boards: they are cheap enough to run them arround 60w per board, especially since this approach allows you to use alu sheet for dissipation, which lowers the ali prices and shipping.
Also remember: a broken diode only means about 0.3% increase in wattage per diode. Get warranty if you can, if not you can still go on using the boards but be carefull with the wattage.

Did I overheat my QB? Broken QB

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