Dimming LED
- Thread starter Tab28
- Start date
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boxer
Active Member
Hopefully someone who knows more than me will chime in and give you some more info. I have built a few diy led fixtures and heres what i know.
If your fixture doesnt have dimming capability then the power supply aka driver is constant current. That means that the output of the driver is what the leds receive directly and there is no way to control it unless you remove this driver and substitute it with a driver that accepts a 0-10v signal and allows you to connect it to a potentiometer or a controller of some sort. Also the driver that you substitute has to be the correct output for the leds you are currently running. This varies with the type of led (1w,3w) or what ever the case maybe.
ReefLEDLights
Valuable Member
Tab28
The drivers are the key.
Its very possible to "jerry rig" a fixture with dimmable drivers.
You would have to first find out the forward voltage range and the total max current of the LED strings. They will most likely be in parallel based on the drivers forward voltage.
There are two types of dimmable drivers Analog and PWM.
Most generic Chinese fixtures like Eshine or Evo use PWM as its cost effective.
PWM (Pulse Width Modulation) turns the LED on and off very fast to simulate dimming. This may or may not affect longevity but may cause a spectrum shift.
The Analog 1-10VDC simply lowers the output current of the driver for dimming. This is what the major controllers like APEX and Profilux use.
Its like 700mA on/off 50% of the time or 350mA constant.
I feel the constant current regulation is a lot better than PWM.
Bill
The drivers are the key.
Its very possible to "jerry rig" a fixture with dimmable drivers.
You would have to first find out the forward voltage range and the total max current of the LED strings. They will most likely be in parallel based on the drivers forward voltage.
There are two types of dimmable drivers Analog and PWM.
Most generic Chinese fixtures like Eshine or Evo use PWM as its cost effective.
PWM (Pulse Width Modulation) turns the LED on and off very fast to simulate dimming. This may or may not affect longevity but may cause a spectrum shift.
The Analog 1-10VDC simply lowers the output current of the driver for dimming. This is what the major controllers like APEX and Profilux use.
Its like 700mA on/off 50% of the time or 350mA constant.
I feel the constant current regulation is a lot better than PWM.
Bill
spero
Community Member
Nice job Tab, was literally going to post something very similar. I just received an email back from JBJ today after I inquired about installing a dimmer on their 89w LED setup.
The LED's on that unit are STRONG and I would love to install a dimmer. On a more advanced level, I'd like to customize the lights a bit more.
ReefLED - Wish you guys were local. You know anyone in the South Florida area that can customize LED units?
The LED's on that unit are STRONG and I would love to install a dimmer. On a more advanced level, I'd like to customize the lights a bit more.
ReefLED - Wish you guys were local. You know anyone in the South Florida area that can customize LED units?
OP
OP
Tab28
Valuable Member
Thanks for info. That is what I figured. The led unit I purchased is said to be same intense as a 250 mh in a tank of my depth. That is what it is replacing so I hope it will be fine. I hope this unit will help educate me a bit on what I want/need on my next better unit which will be a DIY.
