My lights finally arrived! Pictures and a review of the Taotronics LED

From Orpheks website.
Using a dimmer or other electronic control shortens LED lifespan by up to 60%.
Not sure why such a statement was made but it just goes to show you can't always believe what you read. Apparently their is no truth to that statement but for me when I was buying this fixture I thought the KISS method was a far safer path. I guess we will know soon enough.I am by no means an electrician or led pro.Quite the contrary; I was just relying on what I thought would be experts of some sort.

 

Up to 60%! That's outrageous. Running LEDs lower than the max would in no way harm them, only help them. Less power means less heat, and less strain on the LEDs. Perhaps they are referring to effects like thunderstorms, where LEDs go from 20% to 100% for only an instant. Slowly ramping up and down will in no way harm the diodes. I have built a ton of fixtures myself and know this from experience, plus if look at the spreadsheets on crees, they are more efficient as far as wattage to heat & light at lower current.

 

Found this quite interesting.

The only issue with dimming would come from a PWM controlled current-source that doesn't vary the current output via the PWM signal, but rather just outputs in a PWM fashion, with a current limit. Without the proper circuit on the output of the current source, you end up with huge spikes when the source first turns on, which can indeed kill an LED. This is the ONLY circumstance that I can think of that would sufficiently satisfy their statement of "dimming can lower an LEDs lifespan". However, MOST LED manufacturers will openly state that for extremely short duty cycles, you can run LEDs at extremely high currents (10x normal).

 

PWM as a direct input would rarely be seen in the hobby. 10x the norm, now I wouldn't try that, lol

 

PWM is how most LEDs are dimmed these days. Flashlights especially. It dramatically increases LED and Battery life. PWM will keep the drive current constant for no color shift. The Pulsing reduces power usage and keeps the LED cooler.

I have only seen one true PWM driver being developed for aquarium use. The Meanwells take a PWM input but output is voltage level. With IC controlled PWM you should have no voltage spikes.

What can decrease LED life is Voltage/Amperage. Ether overdriving or underdriving. LEDs do have a minimum drive current. Why a lot of the dimmables only go down to 15-35% minimum.

My opinion is just adjust your dimables to the output you need you your tank and don't mess with the Sunrise/Sunset BS.

 

Dimming does not result in a loss of efficiency. During dimming, the LEDs are still operated at the same voltage and current as during full light output. In addition, lamp life is not affected by dimming, as is sometimes the case with frequently dimmed fluorescent lighting. Rather, dimming LEDs may lengthen the useful life of LEDs, because dimming can reduce operating temperatures inside the light source.
LEDs Magazine - Controlling LED lighting systems: introducing the LED driver
Found this, thought I'd share

 

They are not run at the same current when dimmed, current determines brightness. Yes, they are run at the same voltage, however there is a slight decrease in the voltage needed at lower currents.

 

A few months ago I bought this taotronics led fixture:

http://www.amazon.com/TaoTronics-TT...qid=1344409828&sr=8-2&keywords=Taotronics led

This thing is insanely bright... I chose this unit over the 120w model because of the remarks about this newer model being much quieter, and comparatively, it is. I was unprepared for the intensity of these LEDs and even at 18" from the water surface and with a glass lid every SPS coral I put in my tank starts to go pale after several days. The corals are about 12-14" from the water surface in a 24" deep 60 gallon cube.

I do like the fixture and my corals are growing; the colors don't look so good but they are improving. I suppose what I am looking for here is a bit of advice as this is my first LED fixture. My photoperiod is 11am blues on, 2pm whites on, 10pm whites off, 11:00pm blues off. I have considered slowly reducing the photoperiod, especially the whites, but I have been slowly adjusting the fixture higher up to this point instead. I'm a little hesitant to move the fixture any higher because of the LPS that are down near the bottom of the tank.

What do you guys think?

 

I have the 120W Taotronics- LOVE it!

I run the blues 10 hrs a day, the whites 8 hrs a day, one hr of blue only before and after the whites add to the blues.

My corals and colors are doing great.

 

Nice light fixtures.