Project LED

[Midwest Express]

The talk is all about a big buffet platter of awesome covered in grav-awesome, with a side of awesome and tall frothy glass of awesome, finished with some awesome à la mode!

Just sayin... 

[HUNGER]

The talk is all about a big buffet platter of awesome covered in grav-awesome, with a side of awesome and tall frothy glass of awesome, finished with some awesome à la mode!

Just sayin... 

nice

[Wall_Tank]

Yikes........wheres all that heat.........

My fan used to run all afternoon.   Now it runs 25% of the time.   This winter, I may have too low evaporation that I may have problems being able to add Kalk in top off.

[HUNGER]

just walk out the door its outside

[Wall_Tank]

well thanks to wes for stopping out the results are in.  the heat sink with 35 leds came out to be exactly equal to a 10k 250 watt halide.  We got about 750 par just below the water surface,  400 at the midlevel of the tank and maintained 200 on the sand bed.  My lights are about 10 in. off the water surface and I use 80 degree optics.  probably could have gotten alittle better with 70deg optics.  I have mine running on 700 mA ballast drivers.  Pauls will be even more kick butt since he is using 1000 mA ballast drivers.  We tested these readings against my 10k 250 watt bulb and a 20k 250 watt bulb.  The readings were all but one and the same of the 10k bulb.  When testing the 20k we got right at half of the 10k.  so the end results are the led's have the same strength of usuable light that the 10k halide has with more color range of a 15 to 20k color range.  After this confirmation I am extremely happy with this project.
jeff

So I was playing with the par meter today.   My tank is a 90 gal tank.  So I have two fixtures.   These measurements were all done with the pumps all running in the tank.  My Vortecs chop the surface of the water quite a bit, so the values I read from the meter were average values at a given point.

-  Running 250w MH DE bulbs  (14k Reeflux bulbs)  Also had a t5  50/50 and Actinic bulb running.  I had about 250par about 10" under the water.   Par at the sandbed was about 150-170.   I would have to blame this on the Parabolic reflectors MH fixtures I was using.

Now I'm running only LED's - no T5 light
LED setup is 35 - 3 Watt CREE XR-E Per fixture (18 White, 17 Blue)

With No Optics, At the same depth as above, Par was about 220  (LED's driven at about 700ma)
Adding 80degree optics added 80 points to the Par value.   Added 50 points at the sand bed
Driving the LED's to the full rated 1000ma, added an additional 50-60 par.

[Midwest Express]

Drool!   

[HUNGER]

wow thats good

[cyberwollf]

Sounds like a good starting point.  man i wish MH were as easy as dialing up or down voltage for more par lol

[TechGuy]

So I was playing with the par meter today.   My tank is a 90 gal tank.  So I have two fixtures.   These measurements were all done with the pumps all running in the tank.  My Vortecs chop the surface of the water quite a bit, so the values I read from the meter were average values at a given point.

-  Running 250w MH DE bulbs  (14k Reeflux bulbs)  Also had a t5  50/50 and Actinic bulb running.  I had about 250par about 10" under the water.   Par at the sandbed was about 150-170.   I would have to blame this on the Parabolic reflectors MH fixtures I was using.

Now I'm running only LED's - no T5 light
LED setup is 35 - 3 Watt CREE XR-E Per fixture (18 White, 17 Blue)

With No Optics, At the same depth as above, Par was about 220  (LED's driven at about 700ma)
Adding 80degree optics added 80 points to the Par value.   Added 50 points at the sand bed
Driving the LED's to the full rated 1000ma, added an additional 50-60 par.

Thats what I needed to know! It seems everyone is running them a bit low. Whats the max current of the LED's? The rated life, what percent of the max is that?

[Wall_Tank]

Thats what I needed to know! It seems everyone is running them a bit low. Whats the max current of the LED's? The rated life, what percent of the max is that?

The the Cree XR-E's max current is 1000ma.  to Drive at that current, you need a voltage of 3.7v per LED.   The datasheets are a bit vague.  But they say that they will maintain >70% of their output at 50,000hours.  The caveat is that you don't overheat them.  <80C junction temperature.  Of course you cannot measure the temperature at the junction.  So keep them as cool as possible.  Like any semiconductor they operate better cold.

If I didn't have a controller doing dimming control.  I would probably go with 1000ma drivers on the whites and 700ma drivers on the blues.  That appears to yield a nice 12-14k appearance.

[HUNGER]

so 10 hours a day that will last about 13 years?

[TechGuy]

Speaking of cool. Mendalsons has a bunch of peltier units mounted to heat-sinks you may be able to use. Would have to remove the bottom sink, and mount a solid plate on it for the leds. That would keep them cool.

[Wall_Tank]

Speaking of cool. Mendalsons has a bunch of peltier units mounted to heat-sinks you may be able to use. Would have to remove the bottom sink, and mount a solid plate on it for the leds. That would keep them cool.

Where at in that massive upper floor.

[HUNGER]

ya on 2nd floor ya going to get one to cut up to make some little holders for some leds to hang off the mh refltors  there like 5 bucks for a 9inch by 9inch piece

[motley]

just placed an order for the 24led kit.  with what i have been reading this should replace a 250mh over a 65 show with mainley lps coral. 

[CoralBeauties]

the 24 leds should work out for lps.  what is the length of the tank?  Might be a stretch for just 24 leds to cover your tank.  24 leds will be close to the strength of a 250 watt 20k bulb.  Mine tested out with 36 led to be equal to a 10k bulb with the color of about 14k .
jeff

[motley]

my tank is 36l 18w 24h  im going to starte with 18 cool white and 6 blue led all run by two dimmable manwell ballests.  just thought id play with it till i get it just right. and may add 12 more led's depending on what it looks like. and how the corals are

[Wall_Tank]

That is going to be pretty white.  What K range are you shooting for.   I'm running 18 white and 17 blue. on each of my fixtures.

What meanwell drivers did you get?

ELN-60-48D's can run 14 3Watt CREE LED's at full power (50-51volts, 1000ma).   Your going to need a voltmeter and a current meter to tune the drivers properly so you don't overdrive.   I set my dimmable circuit to a full 10vdc, then tune the voltage and current trim pots to get the max current......the voltage should fall where it wants to, provided your not pushing more power than the driver will give you.

I also have some ELN-30-27D drivers that should run about 8 of the 3W CREE's......have to finish that project yet.

[motley]

i looking for a 12k and yes it's the 60-48d ballast

[TechGuy]

Where at in that massive upper floor.

Just seen this post. Second floor, near the PC stuff. Very edge, of the first isle.

What in the holy crap happened to the forum just now?

Lazy, quit tinkering lol.

[Wall_Tank]

i looking for a 12k and yes it's the 60-48d ballast

Pretty sure my arrangement is in the 14-16k range.

[motley]

Pretty sure my arrangement is in the 14-16k range.

alright thanks im also going to use my t5 blue +  to even the color out alittle bit.

[CoralBeauties]

how large of a heat sink?  my sink is 14 in, I have the 80deg optics and am about 10in off the water and mine wouldnt do a good job on a 36in tank in the way of coverage for the whole tank without mounting it pretty high.  i agree with wall you will have a pretty white looking light.  You will need your supplemental lighting to soften the color.  I also went with a 50/50 mix of whites vs blues and the look is just about perfect color wise.
Jeff

[motley]

my heat sink is just 8 by 12 im planning on adding around 12 more led's later to replace the t5's.  could i use like 18 or 16 guage wire to wire them or would it be best to go with 20 guage hobby wire?

[Wall_Tank]

16 or 18 gauge wire is a bit to thick.   Will be harder to work with.   Not sure what you mean by hobby wire, but 20 gauge wire is not a problem