DIY LEDs - The write-up

[TheFishMan65]

2) When adjusting the current in the driver, do I adjust to 800ma and each string will get 800ma, or do I adjust the driver to 2.4amps and each string will get 800ma? I am thinking it is the ladder, just want to make sure.

Your right 2.4 divded by the number if string. IF they have been balanced. They will all run at the same voltage but manufacturing tolerances may allow some to be more efficient. Read this as allowing larger current flow at the same voltage. So you might get string running at 1 amp .6 amps and .8 amps or some other combination that will add to 2.4 amps.

3) Any advice on fuses? Maybe something that is rated at 1amp? Are they rated on amps only, or is it volts and amps?

They are rated as I understand in current and the rate they will blow blow. You want smoething that will blow fast.

 

[chris023]

Your right 2.4 divded by the number if string. IF they have been balanced. They will all run at the same voltage but manufacturing tolerances may allow some to be more efficient. Read this as allowing larger current flow at the same voltage. So you might get string running at 1 amp .6 amps and .8 amps or some other combination that will add to 2.4 amps.


They are rated as I understand in current and the rate they will blow blow. You want smoething that will blow fast.

Cool, thanks a lot.

 

[neltnerb]

Here's the basic setup:

I would strongly recommend connecting the two balanced chains of LEDs together at each junction. This makes it so that imbalances in forward voltage aren't propagated, giving a higher likelihood of balanced operation.

That is, if you have to use parallel chains at all. Generally it's considered poor form because the device law for diodes means that if one chain is a lower forward voltage than the other, it will get a dramatically higher percentage of the current.

 

[MosMike]

I caution you NOT to use the drivers MosMike is recommending. They send lethal voltages across your strings.

Our LED rigs have a huge number of bare electrical exposures.

Thanks for the warning! Actually I was not recommending them as I have yet to see them. But the manufacturer claims that they are UL listed... But nethertheless, with 100V in the string the usual LEDs on stars are not suitable due to leakage current in humid environment.

My personal building procedure is to:
1) check for possible shorts with a multimeter
2) seal all the bare wires with a sealant
3) fire up the fixture!

BTW is there a thread here on electrical safety of DIY LED builds? With bigger builds it should be a concern.

 

[kcress]

Well, got in touch with Meanwell directly and here is what they told me about the HLG-320H

"Hello Mark,

This series is still under developing, will take another 3--6 months to release.

So sorry for the delay.

Kind regards,
Natalie Chen
Mean Well USA, Inc."

I guess I need to come up with another option for how I plan to do this.

Well that SUCKS! :furious: :hmm3: Why are they listing it at all, if it doesn't exist.

Seems we are limited to 240 Watt or smaller units for now.

MosMike; No 'safety thread' per se, but a lot of bits throughout this thread.

 

[neltnerb]

I would strongly recommend connecting the two balanced chains of LEDs together at each junction. This makes it so that imbalances in forward voltage aren't propagated, giving a higher likelihood of balanced operation.

That is, if you have to use parallel chains at all. Generally it's considered poor form because the device law for diodes means that if one chain is a lower forward voltage than the other, it will get a dramatically higher percentage of the current.

To clarify what I mean by this, check out the attached diagram. Because each stage of LED forward voltage drop is independent, you don't end up with statistical correlations in forward voltage resulting in as large of a problem.

 

[chris023]

So here is where I am at with this design so far. I did switch it up a bit with respect to the number of LEDs. I am going with 96 total. I would love input on if you think this is a decent amount.

Not sure on the height above water line just yet. I plan on using ~60 degree optics for all. Lets just say 12" for now, my current canopy is only 6" off the water, so a new canopy would be needed regardless of what the final height decision is, so I am open to height suggestions as well. Just keep in mind that a canopy is a must in my situation. I do have quite a bit of SPS in my tank near the top of the tank. You can see a picture of my tank on page 233, post 5814 if that helps.

I am setting up to drive these in parallel series even though I do have concerns, mostly on balancing the strings Vf. Feels like this parallel or not is like a glass vs. acrylic thing... From what I am reading anyways.

I have searched and searched and have found few threads where people mention are making or made large arrays, but no real details on the drivers/parallel string aspect of things. So other than the advice I am getting here (which is greatly appreciated BTW), I feel like no one has documented their specific work with respect to this very much (pictures, etc.). Most threads out there are on smaller builds. Anyways, I did see a thread that is somewhat current where a fellow reefer is also building 96 LEDs and using 8 ELN-60-48s, there was a brief mention on parallel but nothing more. Didn't seem to be a concern to use 8 mean wells. No biggie, just thought I would mention it...

 

[spamreefnew]

I to just want to say thank you to all who helped me design my led system on here! I am still waiting for my heat sink from heatsinkusa when the thing gets here I will post some pics.

rapidled=
heatsinkusa=

 

[maddog2002]

Is anyone trying to use Mean Well LPC-35-700W for XPG ?
What is min and max number per string if XPG?

 

[kcress]

Is anyone trying to use Mean Well LPC-35-700W for XPG ?
What is min and max number per string if XPG?

I haven't heard of anyone using one of those but there's no reason not to if you can buy them somewhere.

48V is the maximum so how many 3.3V LEDs add up to a number below 48?

9V is the minimum voltage But you better not crowd that so I'd say no less than 4 LEDs.

Note, there is no dimming and no current adjustment. 700mA is what your string will be running at.

 

[afboundguy]

Argh... I can't decide if I want to drop the $500 for a 36 led fixture or $170 to replace my old t5 bulbs and reflectors... I've been digging up some research that makes me a little hesitant on LED's at the moment...

What's the longest people have been using them while still getting visible growth?

 

[mseepman]

Is anyone trying to use Mean Well LPC-35-700W for XPG ?
What is min and max number per string if XPG?

I've got a mix of 5 XP-G CW and 5 XR-E RB from Rapidled on an LPC-35-700 and they work beautifully.

 

[wfournier]

Argh... I can't decide if I want to drop the $500 for a 36 led fixture or $170 to replace my old t5 bulbs and reflectors... I've been digging up some research that makes me a little hesitant on LED's at the moment...

What's the longest people have been using them while still getting visible growth?

It sounds like someone is saying that growth stopped or will stop, where did you get that information? I would put the burden of proof on that claim not on people who are seeing growth (it sounds a bit hokey to me). I do know of someone locally who is running a solaris fixture and has been since they were available so that is quite a while.

 

[maddog2002]

Thanks!
I am using 24 XPG and 24 XPE- Royal Bule on two 23x4.25 heat sinks. Each heat-sink has
12 XPG cool White and 12 XPE - Royal Bule. XPEs are using LPC-35-700. XPG are using 48D but current 48D is out of stock. I am template using LPC_35_700 for XPG until the 48D arrivals.
After I finish the first 24 LEDS on one Heat-sink.
12 XP-G leds are drove at 700MA same as 12 XP-E. After I put it over the tank, The colors look very white and yellow for me. Looks the same XP series, the XP_G has much more output than XP-Es.

 

[wfournier]

Thanks!
I am using 24 XPG and 24 XPE- Royal Bule on two 23x4.25 heat sinks. Each heat-sink has
12 XPG cool White and 12 XPE - Royal Bule. XPEs are using LPC-35-700. XPG are using 48D but current 48D is out of stock. I am template using LPC_35_700 for XPG until the 48D arrivals.
After I finish the first 24 LEDS on one Heat-sink.
12 XP-G leds are drove at 700MA same as 12 XP-E. After I put it over the tank, The colors look very white and yellow for me. Looks the same XP series, the XP_G has much more output than XP-Es.

Yes that is why people recommend at least 60:40 ratio of blue to white when using XP-G's.

 

[der_wille_zur_macht]

As with any change in lighting, different corals respond differently. I've had a very small number that did poorly under LEDs, but the vast majority thrive. The number that did poorly has been low enough that it could easily be attributable to other causes.

Some change colors, but IMHO that's often a "neutral" change, not a negative one (i.e. I had an acro that changed from pale purple to baby blue. I had a monti that changed from drab orange to dark purple. And so on.)

 

[chris023]

Looking for some feedback on a design
LED count/color mix.
LED placement spread/height.
Drivers - is this the right one? Not sure on the 'H' in HLG-150 vs. HLG-150H. Definitely what dimming capability. Think I need a 'B' type (mentioned by kcress in previous post). Where is a good place to buy the drivers?

LEDs will be mounted on u-channel.
Planned on 60 degree optics. Not sure on a good height above the water, as you can see by the below photo of the tank that I have some coral fairly high up in the tank (current T5 setup). Planning on driving a parallel series setup like kcress advised.

Let me know what you think... thanks.

 

[The Grim Reefer]

Looking for some feedback on a design
LED count/color mix.
LED placement spread/height.
Drivers - is this the right one? Not sure on the 'H' in HLG-150 vs. HLG-150H. Definitely what dimming capability. Think I need a 'B' type (mentioned by kcress in previous post). Where is a good place to buy the drivers?

Planned on 60 degree optics. Not sure on a good height above the water, as you can see by the below photo of the tank that I have some coral fairly high up in the tank (current T5 setup). Planning on driving a parallel series setup like kcress advised.

Let me know what you think... thanks.

Nice tank, what size is it?

 

[chris023]

Nice tank, what size is it?

Thanks...
150... 60x24x24

 

[kcress]

Looks pretty good to me.

You might consider doubling the number of U-channels and running twice the LED to LED spacing. Otherwise pay attention to forced air cooling aspects. You might not need it but don't paint yourself into a corner where it would be hard to add.