LED K output when using dimmer.

Killgore · 11/25/2012, 08:28 AM

Hi there,
I recently decided to go with LED lights. I have been looking online, but can't find any real information about this topic. What I'm wondering is if the Kelvin changes on a LED when used in conjunction with a dimmer... for example if they are 10K LED's and I dim them to 50% power... will the K be reduced? I guess if I had to speculate I would assume it does change, but does anyone have any references out there that would be more specific? There's no charts on the subject and I've searched far and wide. What about a 6500K? 460nm blues?
If anyone can point me in the right direction that would be great.
Thanks

jerpa · 11/25/2012, 08:56 AM

There is likely a spectral shift when LEDs are dimmed by adjusting current. I've never seen anything published where it was studied and I would imagine it would vary from one LED to the next. This is one reason some see PWM dimming as a better solution. It dims by switching the LED on and off at full power. In theory you shouldn't have any shift when dimming with this method.

Killgore · 11/25/2012, 09:20 AM

Interesting... I'll have to read a bit more into that. I d know that I'll constantly use the dimming feature in the long run... I'm more concerned about acclimating what I have now to the new light. I'm going from t5ho to LED in about a week. Guy told me to run the lights at about 50% initially. I was concerned about the possible K change and didn't want to "starve" the corals. I guess I'll see how it goes... Thanks again.

11/25/2012, 08:28 AM	#1
Killgore Registered Member Join Date: Sep 2012 Posts: 16	LED K output when using dimmer. Hi there, I recently decided to go with LED lights. I have been looking online, but can't find any real information about this topic. What I'm wondering is if the Kelvin changes on a LED when used in conjunction with a dimmer... for example if they are 10K LED's and I dim them to 50% power... will the K be reduced? I guess if I had to speculate I would assume it does change, but does anyone have any references out there that would be more specific? There's no charts on the subject and I've searched far and wide. What about a 6500K? 460nm blues? If anyone can point me in the right direction that would be great. Thanks __________________ Whoever fights monsters should see to it that in the process he does not become a monster. And if you gaze long enough into an abyss, the abyss will gaze back into you. Friedrich Nietzsche Current Tank Info: 29g mixed reef/10g refugium.

11/25/2012, 08:56 AM	#2
jerpa Registered Member Join Date: Apr 2011 Location: Pittsburgh Posts: 2,174	There is likely a spectral shift when LEDs are dimmed by adjusting current. I've never seen anything published where it was studied and I would imagine it would vary from one LED to the next. This is one reason some see PWM dimming as a better solution. It dims by switching the LED on and off at full power. In theory you shouldn't have any shift when dimming with this method. __________________ Jer Current Tank Info: 40b basement sump, 40b refugium, 30g frag

11/25/2012, 09:20 AM	#3
Killgore Registered Member Join Date: Sep 2012 Posts: 16	Interesting... I'll have to read a bit more into that. I d know that I'll constantly use the dimming feature in the long run... I'm more concerned about acclimating what I have now to the new light. I'm going from t5ho to LED in about a week. Guy told me to run the lights at about 50% initially. I was concerned about the possible K change and didn't want to "starve" the corals. I guess I'll see how it goes... Thanks again. __________________ Whoever fights monsters should see to it that in the process he does not become a monster. And if you gaze long enough into an abyss, the abyss will gaze back into you. Friedrich Nietzsche Current Tank Info: 29g mixed reef/10g refugium.