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PIPSTER
03/03/2015, 04:53 PM
I have a EG style chinese LED light, and I want to turn the whites down more. (The blues, too, for that matter.)

The lowest setting on the dimmer seems to be about 40-50%, still.

Do I need to be looking to replace the dimmer? Or the driver? Or both?

I'm not an electronics expert at all.

coralsnaked
03/03/2015, 04:59 PM
Did they say dims from 0 - 100 % ? This type dimmer is a little more expensive and not always available on the cheaper Chinese fixtures. Probably got what you got ! Most dimmable fixtures just route that wattage back into the transformer and some cannot handle dimming down past 50%

PIPSTER
03/03/2015, 05:20 PM
I just want to know what I have to replace to get 0-100% dimming.

Gorgok
03/03/2015, 07:26 PM
What are you using as a dimmer?

Replacing the drivers with drivers capable of dimming would solve the issue though.

PIPSTER
03/04/2015, 07:59 AM
The light has dimmable drivers and uses a dimmer pot which seems to only go down to about 40-50% dim. I don't know if it's the dimmer pot or the drivers that doesn't just go down to 0%, or close to it. I would be happy with 10%. It's the same basic light as reefbreeders\marsaqua\reef radiance.

oreo57
03/04/2015, 08:26 AM
The light has dimmable drivers and uses a dimmer pot which seems to only go down to about 40-50% dim. I don't know if it's the dimmer pot or the drivers that doesn't just go down to 0%, or close to it. I would be happy with 10%. It's the same basic light as reefbreeders\marsaqua\reef radiance.
Tese "types" have multiple dimming circuitry, and to make it worse, run high DC voltages. i.e 60-85V
w/out disassemble and seeing what is inside it is impossible to tell.
You may just have a bad "pot".. most dim lower than that I thought May be wrong
http://www.*********.com/forums/do-yourself-diy/173711-aquamanna-others-165w-chinese-light-emitting-diodes-mods-quieter-fans-0-10v-dimming.html

The light is basically 2 serial strings.. So you can work out the specs a bit from that.
There is a lot of history on these types here and at other reef sites.
I've gone down this road before..

http://wamas.org/forums/topic/58230-interested-in-apexrk-controlled-d120s/#entry501442

It is not as easy a question as you might imagine,,

ca1ore
03/04/2015, 12:36 PM
I have the new Kessel lights, and they don't dim down to zero either. Hiwever, the older trulumen strips do, so it's clearly possible.

perkint
03/04/2015, 12:50 PM
As above, not an easy question to answer and may be more than you want to do...

Easiest solution might be to bin the existing drivers and replace them with a single PSU and meanwell LDDs, but that would probably require splitting the strings of LEDs...

Tim

PIPSTER
03/05/2015, 11:11 AM
It sounds like it wouldn't be worth it, as long as the coral can acclimate OK.

mcgyvr
03/05/2015, 11:22 AM
just raise the light higher if you are worried about it during acclimation..
or
put something between the light/tank to diffuse/cut down on the light.

IMO its VERY difficult to walk someone through redoing/modifying,etc.. a LED light fixture over the internet when they have no clue about electronics.

Of course I have no idea what an EG Chinese light is either.. Had I been posting this question I would have included multiple pictures showing internals/connections/drivers,etc...

pwreef
03/05/2015, 09:48 PM
You will need to cut traces so that you divide the 55 (or how ever many total LEDs you have now) into smaller strings. Buy 4 LDD-700H and a 48V 150W power supply as well as a controller that provides PWM dimming signal such as Storm/Storm X/Bluefish, etc. It will cost 2X of what you paid for that light.

PIPSTER
03/06/2015, 08:16 AM
Thanks everybody for the replies. It's clear that it's too much trouble. :deadhorse1:

The lights are soldered to a circuit board, which doubles as the heatsink. I'm deciding to be happy with what I've got, as it would basically require buying a whole new light to get zero dimming.