(Another) DIY LED Build - Linear Design

[nreefer]

Thanks Dennis for the reply, I was unsure on if I could run the 14 LED's per driver.
For the ratio of NW,CW,RB I am copying what I did on my 400 gal display and I really like the colour of it. I was just going to change by adding a few Blue's in the mix and reducing the number of RB from the total. I'll play with some more layouts to see if I can change the ration. Do you think 70 LED's is enough for a system of this size?

 

[nreefer]

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[TropTrea]

Thanks Dennis for the reply, I was unsure on if I could run the 14 LED's per driver.
For the ratio of NW,CW,RB I am copying what I did on my 400 gal display and I really like the colour of it. I was just going to change by adding a few Blue's in the mix and reducing the number of RB from the total. I'll play with some more layouts to see if I can change the ration. Do you think 70 LED's is enough for a system of this size?

That is an extremly tough call since your tank is 36" Tall. If the LED's are 10" above the surface of the water and you have 5" of substate you pushing the light down 41" . On my shallow breeder tanks I moved away from using lenses but in your case without them you will be spilling more light out the sides of the tank. Even with 60 degree lenses you will have light loss.

for you tank I'd try using every ting I could to penetrate the light deep into the tank. An example would be 60 degree lenses on the front row of LED but also have them aimed at a 30 degree angle to the rear. I would use 1 1/2 " channeling for the LED's with a 1" gap between channels to give you roughly 2/1/2" between rows of LED's. With a 3" GAP between LED's on each row you could put 16 LED's in each row. You could go up to 8 rows of LED's for a toatl of 128 total. I personaly would start with just 5 ROWs or 80 LED's. missing row 3,5,7 counting from 1 being in the front. Then if you decide you need more light simply add in additional rows.

Another thing to keep in mind is I do not put every LED in a single row on the same driver. But I try to keep simular LED's on the same driver. This allows me to get a even lighting adjustment and vary the intensity of the light as I turn sets of LED's on and off in the predawn , dawn, midday periods with out drastic light changes between modes.

An example. on your predawn mode I might run one driver with 12 Royal Blues, then for the next stage add in two more drivers running 14 more Royal Blues and perhaps 12 Blues. Then a pre mid day winning one more driver with 6 Whites and 6 more blues. And finaly the Mid day with two more drivers 12 more withes and 10 more Royal Blues.

 

[SWF]

Don't forget heat sinks 1 OHM resistors, heat transfer compound, terminal blocks, and heart sinks.

Thank you so much, Dennis.

For the heat sinks i would be using the C aluminium channels.
would it be 1 ohm resistor for each string of 12 LED's ?
what would be the best to pick for the wires/ gauge and which terminal
blocks?

I am planning to pick the following for the connectors,
http://www.amazon.com/Position-Weat...5ETK/ref=sr_1_4?ie=UTF8&qid=1329117161&sr=8-4

and Heart Sinks ?? !!!

 

[TheFishMan65]

IMHO pushing these drivers to the maximum rating will probably shorten their live some also. Just a general rule of electronics.

 

[TheFishMan65]

Yes, one Resistor for each string is recommended.

 

[TropTrea]

IMHO pushing these drivers to the maximum rating will probably shorten their live some also. Just a general rule of electronics.

It is weid thing with these current drivers. While it is true that the wattage your pushing out of them can reflect there on there life span. However if a driver were designed to run open at 48 volts and youyr load is only calling for 36 volts that extra 12 volts are being absorbed by the driver and converted in heat. Heat is truly the biggest life shortening vasriable on electronic devices. With a driver designed to run at a max 48 volts you will probably find its longest life expectancy if it only need to put out 43.2 volts. This would mean 14 LED's running at 3.08 Volts each or 12 LED's running at 3.6 Volts each. So the biggest variables in if your going to push 14 LEDs would be how much current your pushing and which LED you selected. If you end up dimming them down to the 350 ma range some LEDs will actualy be drawing less than 3 Volts. If your going to have them turned up all the way at 1050ma then 12 is even on the borderline.

 

[Tickyty]

Great thread. Did you purchase all your LED supplies from Rapid LED

 

[TropTrea]

Great thread. Did you purchase all your LED supplies from Rapid LED

My last purchase and probably my next were from Rapid LED. In my early experimentations no one supplier had everything that I wanted. Right now I'd like to get and try some of the CRI-85 and CRI 90 LEDs but so far I have not found a reasonable source for them with STAR mounts. Rapid right now is not listing any 350 ma Drivers which I like to use for PRe-dawn and post Dusk lighting. But overall they do have the most usefull selection and very good prices on what they do offer.

The thing is LED technology is changing every day. With LEDs what is cutting age today may be old school 6 months from now. It was not long ago that a 1/2 watt LED could set you back $17.00. Now they no longer even make 1/2 Watt LEDs and they will tell you to use a 3 Watt LED and run it a lower current.

 

[wardda]

Setting Amps

Setting Amps

I'm getting close to being able to hook up the driver to my build and I wanted to make sure I understand this correctly for setting my base amps....

" I used a 1 ohm resistor connected inline with my LED circuit. Why? On the video above, you need to break the circuit to put your tester inline to know the amps. That is fine, but with the resistor technique, I dont have to break anything. Just put your tester in volts, and then connect it to both ends of the resistor, and tadaa!!! there is your milliamp reading."

I'm not an electric guy but is this written correctly to put your tester in VOLTS to get your amps? I'm assuming this has something to do with the resistor as to why we are measuring volts and the reading is = to the amps?

And am I understanding it correctly that we have the full circuit setup with the resistor in place before the first LED all wired in series and then we just touch the multimeter contacts red on the one side and back on the other side of the resistor?

Thanks for the confirmation ...

There are many ways how to check your milliamp reading thru your tester, one example is from the video above. Another one (the one i used) is by means of a resistor (Thanks to Kcress). I used a 1 ohm resistor connected inline with my LED circuit. Why? On the video above, you need to break the circuit to put your tester inline to know the amps. That is fine, but with the resistor technique, I dont have to break anything. Just put your tester in volts, and then connect it to both ends of the resistor, and tadaa!!! there is your milliamp reading. You can always do this and check your reading anytime you want.

So why not just break it and put your tester inline, like what they did on the video???? Well, there is a danger to that, specially like me, I keep forgetting stuff.... Remember... that when you are breaking off the circuit, you need to turn off the driver first, then put your tester inline, then turn it on. The same thing when removing the tester. If you dont and you forgot to do this, then say bye bye to your LED's.

Here is a pic of my temporary setup showing the resistor (1 ohm 2 watt @ frys $1 for two resistor) connected inline with the circuit.

 

[jgwinner]

I'm not an electric guy but is this written correctly to put your tester in VOLTS to get your amps? I'm assuming this has something to do with the resistor as to why we are measuring volts and the reading is = to the amps?

Correct. You are measuring the voltage drop across the 1 ohm resistor. As we know E=I*R (Volts=Amps*Resistance), if you have a .500 volt drop, as it's 1 ohm, you know it's .500 amps (500 milli-amps).

You'll get an odd reading if you have the meter in amps; it would depend in the internal resistance of the meter; it might divert some current around the 1 ohm resistor. Just use the volts setting. (always think of an amps setting as a short; a volts setting, as an open, across the terminals of the meter).

== John ==​

 

[pfi$h]

Great thread Katchupoy! I am going to do three linear strips of twelve LED's for 36 total leads just like your setup. I have a 48 x 12 x 20, 60 gal reef tank. I plan to do two rows of blue and one white. The difficulty I am having is deciding on the combination of RB to B and CW, NW, WW to use for the best spectrum. I have never used MH and I don't really have a color preference. I plan to use Rapidled. Any thoughts would be appreciated...

 

[TheFishMan65]

I did CW and RB. My next step is changing half the CW the NW, but I have not done that yet. If I did one today 5:1 RB to B and either all NW or 1:1 NW to CW is what I would do.

 

[TropTrea]

Great thread Katchupoy! I am going to do three linear strips of twelve LED's for 36 total leads just like your setup. I have a 48 x 12 x 20, 60 gal reef tank. I plan to do two rows of blue and one white. The difficulty I am having is deciding on the combination of RB to B and CW, NW, WW to use for the best spectrum. I have never used MH and I don't really have a color preference. I plan to use Rapidled. Any thoughts would be appreciated...

I personaly would go with 44 LEDs. 15 on the front rail, 14 on the middle rail and 15 on the rear rail.

color wise I would go with 18 Royal Blues, 18 Blues and 8 Neutral Whites.

The colors I would split the Whites between the two back rails 4 each.

I would use 4 drivers
6 Royal blues and 6 blues on one driver for pre dawn and post dusk.
12 Royal Blues one the second driver
12 Blues on the 3rd Driver with driver 2 and 3 used for dawn to dusk
then the 8 Neutral whites used on the mid day 4th driver.

As long as you use XP series LED's you can run these all on 1050 ma drivers.

 

[hoehnelii]

I was planning on changing the 2x250w mh setup pn my 75g sps tank. I have been reading through all the threads and was wondering if I could get a recipe for amount of leds types etc for my tank. Also if I prefer the 14k look. Thanks

 

[TropTrea]

I have not used dimmable drivers yet but Im considering the maxwells dimmable drivers. But Im also confused as it appears there are multiple ways to dim them. One is simply with a variable resistor, and the other with a variable resistor and 10 volt power supply, and finaly with a pulsed variable duty cycle signal that I do not want to use.

If I put a 10,000K pot between blue and white wire will this allow me to dim the drivers?

Or as I have seen other set up where you need to put a 10 volt DC power supply across the pot than connect the - from the power supply and pot to the blue wire on the driver and the variable leg of the pot to the white wire on the driver.

Then the next question is if need the 10 volt supply can I use one supply to power up several pots and drivers.

Finaly if I get the variable drive and just want to run it at full power do I need to short out the blue and white wires together, do I leave them open not connected at all or do I still need a 10 volt supply and or resistor between them?

 

[TheFishMan65]

hoehnelii,

48 LEDs would probably due. 16 NW/CW and 32 RB/B. Mix is up to you, but see above for some mixing recommendations.

 

[TheFishMan65]

TropTrea,

I am more confused. We need to know what driver you are considering. Some only support one method others all three.

I have not used dimmable drivers yet but Im considering the maxwells dimmable drivers. But Im also confused as it appears there are multiple ways to dim them. One is simply with a variable resistor, and the other with a variable resistor and 10 volt power supply, and finaly with a pulsed variable duty cycle signal that I do not want to use.

If I put a 10,000K pot between blue and white wire will this allow me to dim the drivers?Probably No, the ELN need a 10 volt supply and the HLGs need 100k

Or as I have seen other set up where you need to put a 10 volt DC power supply across the pot than connect the - from the power supply and pot to the blue wire on the driver and the variable leg of the pot to the white wire on the driver.Works for HLG and ELN

Then the next question is if need the 10 volt supply can I use one supply to power up several pots and drivers.Yes

Finaly if I get the variable drive and just want to run it at full power do I need to short out the blue and white wires together, do I leave them open not connected at all or do I still need a 10 volt supply and or resistor between them?Open for the HLG and 10 volts for an ELN

There are other Meanwells out there, but these are the two I am familiar with. If your are considering a different one let me know the model and I will check out the datasheet.

 

[katchupoy]

Great thread Katchupoy! I am going to do three linear strips of twelve LED's for 36 total leads just like your setup. I have a 48 x 12 x 20, 60 gal reef tank. I plan to do two rows of blue and one white. The difficulty I am having is deciding on the combination of RB to B and CW, NW, WW to use for the best spectrum. I have never used MH and I don't really have a color preference. I plan to use Rapidled. Any thoughts would be appreciated...

That is a very subjective question. How many this and that. Are you a blue person? or an iwasaki 65k person.
Here is what I suggest.

1) The CW and NW can be 1:1. So 6xCW and 6xNW
2) 12 royal blues.

3) The third strip will be the deciding factor.
a) if you want 1:1 effect then maybe 6xblues + 6xwarmwhites
b) if you are a blue person then add more blues less WW
c) if you like to experiment, then you can also add red, UV, green and what not.

4) Use if possible the XP LED series. So they are all the same amperage.

Note:
1) you can glue (thermal adhesives) the two strips but you can use screw + thermal paste the third strip. This way you can actually buy several extra colored LEDs and keep shuffling the the third strip until you hit the color you want.
2) If you are using the meanwells, then I really like you to use the dimmables.
3) if you become comfortable with doing DIY, then later you can add another strip, but doing parallel on the third strip. So you can have 48 LEDs on 3 drivers. But thats in the future.

I forgot to ask.... what kind of corals do you have? or you want to keep?

 

[katchupoy]

hoehnelii,

48 LEDs would probably due. 16 NW/CW and 32 RB/B. Mix is up to you, but see above for some mixing recommendations.

@hoehnelii,
+1