QB132's on drivers with higher current than rated max

OkieDan

Member
Hi, I just ordered my first lights for my first grow. I originally planned on getting some Chinese blurple lights, but after a bit of reading, I opted for QB132's. Unfortunately, I think I may have made a noob mistake and ordered the wrong drivers, which I cannot return. From reading around the web, I learned LEDs can draw more current than they can handle and therefore die from thermal runaway. Is that true, and if so, what's an economical solution that is also electrically efficient? I'm assuming I'll need some type of current limiter for each board.

At first I thought the over-current issue could only happen if you have boards drawing their current from other boards in parallel, but after watching some YT videos, I'm not so certain anymore and have the impression that an LED can draw more power than it can handle all by itself and burn out if the extra current is available. Please advise.

8x HLG QB132 3500K
2x Mean Well HLG-320H-36A - Google: HLG-320H-SPEC.PDF

My plan is to weld up an aluminum frame and possibly have some aluminum plates welded to frame that boards will mount to so there is some better heat dissipation.
 

Moflow

Well-Known Member
What do you think is wrong with that hlg 320h 36a driver?
8.9amps max
Max current for qb132 is 2 amps x 4 boards = 8 amps.
Dim them down a fraction and you're good to go. Plus you are gonna use heatsinks and a fan blowing over them lowers temps too if you like.
 

OkieDan

Member
Is the 2A rating on the qb132 the most it will ever try to draw, or the most you should ever make available to it? If 2A is all it will ever draw, then I don't think I'll have any issues. If 2A is the most I should make available to it, then it seems like I could have an issue.

Do I just need to make sure the voltage never exceeds the board's 36V rating?
 

diyled

Well-Known Member
The specified output is never right, and the test report can be off too
"CH1: 4.45A ~ 8.9A I/P: 230 VAC I/P: 115 VAC O/P:FULL LOAD Ta:25℃ 4.327 4.324 A~ A~ 9.785 9.783 A/ 230 VAC A/ 115 VAC"

10amp i would rate that driver at just to be on the safe side.

Either turn the driver down to 8amp with a multimeter and use 4 boards each or use 6 boards per driver.

Using aluminium plate isnt useful unless its been machined perfectly flat. And even them the boards are never perfect. A few PC fans will help more than aluminium plate will.
 

OkieDan

Member
Thanks guys, I suppose since others are running QB's in parallel with CV drivers without problems, I shouldn't have problems either, I was just worried about things I've read regarding LED's and thermal runaway. I will adjust amperage to 8A while driven and I will also match the boards so that 4 boards that come on with the least amount of voltage are on one driver and the other four are on the other driver. I'd like to get 70-75W from each board.

I plan to weld together some 3/4" aluminum angle/L-channel for the frame. I'm not dead set on tent size, I may go with two 2x2 tents or one 4x4.

Does this configuration look OK for a 4x4 tent?
931mm = 36.65 inches
939mm = 36.96 inches

8x QB132 frame.png

QB132 Lighting Top.png

QB132 Lighting.png
 

TEKNIK

Well-Known Member
Thanks guys, I suppose since others are running QB's in parallel with CV drivers without problems, I shouldn't have problems either, I was just worried about things I've read regarding LED's and thermal runaway. I will adjust amperage to 8A while driven and I will also match the boards so that 4 boards that come on with the least amount of voltage are on one driver and the other four are on the other driver. I'd like to get 70-75W from each board.

I plan to weld together some 3/4" aluminum angle/L-channel for the frame. I'm not dead set on tent size, I may go with two 2x2 tents or one 4x4.

Does this configuration look OK for a 4x4 tent?
931mm = 36.65 inches
939mm = 36.96 inches

View attachment 4308738

View attachment 4308741

View attachment 4308742
That looks good, coverage should be very even
 
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