I would like to set-up a few nicha’s 219 that I will run from a solar setup. So the input voltage will be between 11 and 14V. I’m thinking using a driver for each led (or maybe triples in parallel) as they will be placed at least 1.5m apart from each other. I want to be able to dim the LED and run them as high as possible without over heating them with passive cooling. What drivers are recommended for this?
I have some CCCV modules, they work but it’s a pain for controlling the LED with those tiny screws and without an A-metr I might run too much amp into the LED, I also honestly doubt they will last long.
I’ve been thinking bout using flashlight drivers as they are supposed to be designed for beeing very efficient but I haven’t found one that can handle the input voltage and has dimming capabilities. Also the cost might be to high compared to other possibilities.
I don’t mind being creative as long as it not to technical, so any input is welcome.
Have you tried some of these drivers with the PWM controller? Is the PWM noticible? Or there options without PWM?
Looks very interesting maybe I order one + driver and see how it goes.
You can use buck converters that have a tunable resistor for max current and another for voltage
If you put a Potentiometer with knob parallel to the voltage one and so control the output, to get a a finer control over the range where the LED starts to to shine you need a tunable resistor in series to the potentiometer
Sorry I really don’t understand……
I got a few of these although I think the one u are showing is boost convertor, mine look very different and have 3 potentiometers.
mine
You can modify the max current with one for sure
And the others are for voltage setting and max voltage
The max current protects your LED
The dimming of the LED you can do over the voltage setting one
If you put a potentiometer in parallel to the voltage setting one you can control between minimum voltage and voltage where the current limitation kicks in
If you want only control the voltage where the LED starts to shine to max led voltage add a tunable resistor in series with the potentiometer
This might sound stupid but isn’t a potentiometer a tunable resistor?
But if I get this correct: I set my CCCV module to max current and max voltage the LED can take and then just put a potentiometer parallel over the potentiometer of the module that sets the voltage?
How do I calculate or figure out what potentiometer I need?
in german tuneable resistor is small to adjust with a screwdriver and potentiometer one adjusted with a knob
I made a short video
The resistor value of the potentiometer with knob is too big so its too sensitive only regulating brightness in less than 10% of the turn
The resistor for voltage regulation on the Buck has for 3.9V a value of 505 Ohms to meet the drive current of 1.5A for the XPG2
the one for the standby voltage has 171 Ohms while the big potentiometer is 0 Ohms
the tunable resistor for regulating 2.4 to 3.9V
needs to be 640 Ohms or more to regulate the voltage for full current
and to be 0 for no light or minimum brightness
but I had a 10kOhm thats why it reacted only on a fraction of the turning to regulate the current
so you in this setup I need for both external tunable resistors 1k Ohms
its a bit odd, bcs sometimes I dont find the right words
No I havent.
You dont need pwm. You can choose driver with current you need, or change resistor, also you use several switches with different resistors and conctant output without any pwm.
@Lexel: potentiometer vs veriable resistor makes sense now. But I can't view the vid as it's private.... @kiriba: OK like that. I was thinking bout "PWM controller":http://www.ebay.com/itm/Controller-PWM-dimmer-to-control-LED-driver-/112286296801?hash=item1a24c8eae1:g:NeIAAOSwqBJXUZSq I might just try different things, might be nice to play around.
Video is fixed
To make those buck converters dimmable get a 680 small tuneable resistor and 1kOhm large poterntiometer, when on the converter is a 10kOhms tunable resistor for voltage setting
In the video I realized that on low working voltage a 10kOhms works only between 0 and 640 ohms at 3.9V, so its way to sensitive
of course at a higher voltage setting the sizes of the resistors you add will be higher as well
I tested this setup for another project, where I build lights for another BLF member
Well allright, that video explains it great :+1: Thx a lot!
OK
I tester instead of voltage for dimming the current regulation
For this 5A one I can get 0-2.94A max setting with a 10kOhms resistor parallel to the 10K on the board
The linearity is perfect, no need for a idle tuable resistor, but you can add one if you want a minimum setting
I am using the current regulation setting in my project as it isesier to adjust, no offset needed
one thing about current tunable resistor is in that configuration
you cant reach the max current as the combined resistance is always smaller than the original tunable resistor,
a bigger 50k resistor get only 4,47A of 5.24A max.
this can be onlymax current by desoldering the original and replacing it with 20k and the one in series is as well 20k
so that the combined resistance is 10k as the original one