DiY LEDs - How to Power Them

Fastslappy

Well-Known Member
Hello
I have 5 COBs for one Panel with Meanwell HLG 240 1400B. Wich resistor or pot (perhaps 100k Ohm ?) would u use? Sry for my low english i am from europe. thx.
that's the one , add a switch to the circrit & enjoy running @ 105+% or close the circit with the switch & use the dimmer
you would enjoy both worlds being able to dim & the option to run the driver @ max output
 

BioManFreak

New Member
thanks dude ;)
And if I want to use a switch, 700mA or 1050mA, which resistors are to chose? 100k Ohm for 700mA and a 50k Ohm for 1050mA? and for 1400mA without a resitor? thanks
 
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Fastslappy

Well-Known Member
no resistor
simple pot then switch that completes the two leads
with the switch open the driver runs at Max Power close the switch & then the pot comes into play as your dimmer set it to 100% or set to 75 % but it will not run at max power(105+%) with the pot on the circuit
(they are just signal leads Not power leads )
 

pickledlsd

Member
no resistor
simple pot then switch that completes the two leads
with the switch open the driver runs at Max Power close the switch & then the pot comes into play as your dimmer set it to 100% or set to 75 % but it will not run at max power(105+%) with the pot on the circuit
(they are just signal leads Not power leads )
Nice! Really glad I'm reading this forum. Lots of good information here. My light project starts tomorrow.
 

Isawthelight

Well-Known Member
what affect on efficiency does dimming have?
Dimming controls the level of current being serially delivered to the LEDs. Dimming increases LED efficiency. Efficiency is inversely proportional to mAmp current. High currents make the temperature increase, Vf voltage of the LED decreases and this means LED power decreases due to Power = mAmp Current x Vf

Driver efficiency will decrease the dimmer you make it run.
 
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pop22

Well-Known Member
Does the increase in LED efficiency balance out the loss to the driver? or is there still a net loss, however small?
Dimming controls the level of current being serially delivered to the LEDs. Dimming increases LED efficiency. Efficiency is inversely proportional to mAmp current. High currents make the temperature increase, Vf voltage of the LED decreases and this means LED power decreases due to Power = mAmp Current x Vf

Driver efficiency will decrease the dimmer you make it run.
 

PurpleBuz

Well-Known Member
I really appreciate all the input guys. I got the apv because I'm trying to avoid any off brand adapters or cheap stuff that might fail on this light. This is my first light build after watching greengeene's video, and then all of growmau5's videos, and then doing a little research and sourcing. I'm still VERY new and ignorant to alot of this stuff.
The conflicting stuff I'm finding is that some say pc fans with the pwm control need a constant 12v and the speed shouldn't be adjusted by the voltage but by the pulsing signal from the pwm wire (computer motherboard). I obviously don't have a motherboard in this light so I may simply drop the voltage and if the fans die I can replace them with ones that don't have integrated pwm control.
Mistake on my part, I should have dug further before buying the things I did. Ideally, I would love a toggle switch with half and full speed or even a potentiometer to adjust the fan speed the way I can adjust the cobs with the b100k. It would be even better to control both the cobs and the fans with one potentiometer but that's dreaming big on my part considering my lack of knowledge.

suggest you ignore most of the airheads. Use the apv-12-12 for the fan. its simple and robust and easy.
If after your done assembly and testing find that the apv-12-12 is blowing more air than needed, then get a lower voltage apv , maybe the v or the 5v and switch them. no harm and you can "optimize" later.
 

pickledlsd

Member
suggest you ignore most of the airheads. Use the apv-12-12 for the fan. its simple and robust and easy.
If after your done assembly and testing find that the apv-12-12 is blowing more air than needed, then get a lower voltage apv , maybe the v or the 5v and switch them. no harm and you can "optimize" later.
Thanks PurpleBuz. Most of my parts arrived today and the plan is to use the apv 12-12 and see how it works. Dawg is doing this with a very similar setup. I do appreciate the idea of the lower voltage apv if the 12-12 seems too much, we'll see what happens.
 
I was wondering what the opinions were on powering 9 CXB3590s? I am guessing that the answer I am going to hear would be to simply use 3 drivers. Not sure if there is a good way to use two or possibly one?
 

sanjuan

Well-Known Member
I was wondering what the opinions were on powering 9 CXB3590s? I am guessing that the answer I am going to hear would be to simply use 3 drivers. Not sure if there is a good way to use two or possibly one?
I'll assume you have the 36V version. Mean Well HLG-240H-C700 will drive 9 of those at a little under 25W each. The HLG-185H-C700 will drive 8. At that low power you probably don't need a fan if you have an appropriate heat sink.
 

ThaiBaby1

Well-Known Member
Hi guys,
I am wanting to do a build with 3590,s. Could I buy a meanwell 240h 1400 and dim it to 700?, that way I could bump it up later to 1400 if I wanted
 

sanjuan

Well-Known Member
Hi guys,
I am wanting to do a build with 3590,s. Could I buy a meanwell 240h 1400 and dim it to 700?, that way I could bump it up later to 1400 if I wanted
Yes. HLG-240H-C1400A dims to 50% with an internal pot. The "B" model can dim down to 10% with an external potentiometer or resistor.
 

giantsfan24

Well-Known Member
I'm at the cree product characterization tool. I've attached a screenshot and I'd like to know what the circled value means.
"LED W". Any help?

Cree Product Characterization Tool.png
 
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