LT lurker here, want to pick your brains for specific answer without the trolls and grief? :)

For one fan, and theyre only rated at .27a which is why i've opted for such a small power supply for them

So that light seems to be working well, to be honest i've never been interested enough to measure voltage or amp draw and I still have no par meter so I have no idea how much light this thing is actually putting out, but i'll say this, this is the brightest source of light i've ever seen in my own experiences, i've included a few pictures yes its ridiculously rigged but its functional

I have a new question, based upon the assumption that the math you did for my previous light is correct and i'm only running it at 2.3-2.5 amps that would leave quite a bit of headroom to push it harder correct? Since this cob is rated at 5.75 amps max. I have ordered an HLG-320H-54A but if I cannot put power on the psu without a load how can I determine what voltage its currently at? The A model allows you to manually control voltage and current independantly if I had realised this initially I wouldve not bought the B version of my initial psu. If voltage is outside of the voltage range of my cob, the.... CLU056 4000k etc etc. then, will it damage it?, Would a multimeter be enough of a load to wire in with this psu to be able to set it before wiring to my cob? Unsure of how to proceed, any advice would be appreciated.

I won't say I recommend starting the driver with no load but I did it to all of mine before I wired it up and have no issues. If you decide to do it make sure both wires are separate and have no way of touching anything besides the multimeter leads. Also beware that much current can kill you very quickly so be careful

Hm that makes me wonder if i've heard to not power them without a load is simply a safety concern, i'm in no hurry though i'll wait for someone who can tell me specifically why I shouldn't do it and whether or not it could or will damage my cob

Sliranax said:

So that light seems to be working well, to be honest i've never been interested enough to measure voltage or amp draw and I still have no par meter so I have no idea how much light this thing is actually putting out, but i'll say this, this is the brightest source of light i've ever seen in my own experiences, i've included a few pictures yes its ridiculously rigged but its functional

I have a new question, based upon the assumption that the math you did for my previous light is correct and i'm only running it at 2.3-2.5 amps that would leave quite a bit of headroom to push it harder correct? Since this cob is rated at 5.75 amps max. I have ordered an HLG-320H-54A but if I cannot put power on the psu without a load how can I determine what voltage its currently at? The A model allows you to manually control voltage and current independantly if I had realised this initially I wouldve not bought the B version of my initial psu. If voltage is outside of the voltage range of my cob, the.... CLU056 4000k etc etc. then, will it damage it?, Would a multimeter be enough of a load to wire in with this psu to be able to set it before wiring to my cob? Unsure of how to proceed, any advice would be appreciated.

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Have you calculated how much cooling you need for 5.75 amps? I would push the brakes a bit...Your going to need some major cooling, considering your efficiency will drop like a rock even with adequate cooling, so you probably will need to dissapate 2-3x the amount of waste heat as compared to now.........that's the 1st consideration...2nd what is the vF @5.75 amps, have you calculated that or looked at the datasheet?

Might need to go back to basics here.....in term of electronics theory....what is current, what is voltage, the product is wattage, How is Tc calculated and its relationship with the Ambient temps [Ta] and how to calculate that or at least ballpark it with the datasheet, for a Tj [juntion temp] which is related to vF again...

There is a lot of calcs, I would tread slowly if you are unsure

Well in truth there isn't a lot of understanding on my part with electrical theory etc., what I am doing is assessing the consensus of the community and leaning on youre experience I have a vga cooler en route for it, TDP is 300 watts, and I guesstimate using no more than 270 watts or so in order to avoid exactly what youre concerned with meltdown. With that being said, I dont have a probe to solder to my cob for the Tc temperature reading, but best guess with my infrared thermometer is around 60c, hard to tell with the glaring light and angle but that's an average from multiple angles pointing beside the LES, and I was told I was putting roughly 130 watts through this cob as is now, which i've mounted on a 230w TDP cpu cooler, its been running for a few months grew that tomato plant in the pictures which have fruit on them, which just amazes me, though I have noticed slower growth than outdoors, but anyway i'm diverging. What i'm getting at I guess is I feel comfortable with the cooler i've purchased for this cob and feel safe up to probably 4.5-5 amps, again a rough guesstimate but if it burns up i'll go buy another, fire extinguisher is handy. ambient temp? egh 73-75 F But I do appreciate youre concern, perhaps you could tell me if i'm pretty well in the safe zone based upon youre understanding of the math?