Explain Mean Well LDD's like i'm five...

[oreo57]

Right now im having a similar problem... i know the ELN/PLN drivers, but nothing about PSU and LDD. Here's what i got going on...

Looking at making just 2-3 "spot lights" for now to target 3 specific corals. Eventually in the future i plan to upgrade this as i can by adding more "spot lights" until the entire tank is lit with LED as i get more money. So, from what ive seen, LDD and PSU is the way to go... for the spot light im looking at right now. To make each one i plan on

2 cree CW XP-G2 (1500mah)
2 cree RB XT-E (1500mah)
1 semiLED UV (750 mah)

Each color on a separate driver and dismantle with POT

So, for 2 spot lights.
4 CW
4 RB
2 UV

1 LDD 700
2 LDD 1000

Power supply im looking at http://www.invertersupply.com/media/data/DV480.pdf

So, how do i wire this ans work it so that i dont burn the leds out until i get more of them to run full strings? And then... how do i run said strings?

Say you start w/ the 48V power supply..After accounting for LDD "losses" you are left 45V.

Voltage adds in series, so at say 3.6 V(f) - 12 diodes in series.

Basically 3 "pucks" worth for one CW channel.
Same for WW.

Once the first is built, your done.. The LDD will control the voltage so to speak.. First only allowing 14.4V (concentrate on just one channel for now, the others will be similar)

to reach the 4 diodes. When you build the next you just cut the neg and run it to the pos of the next set of 4. now the LDD will "allow" 28.8V.

adding the 3rd puck and you get 43.2V

You now ran out of voltage..

Anyways each channel is figured the same and behaves the same..

After this you need to add more Ldd's and start another "chain"..

Doesn't really matter how many "amps" the power supply has as long as it is initially over 2.7A..(est. BASED solely on adding Ldd's ACTUAL amps would need to be calculated per string)

adding another chain of 3 in parallel.. 5.4A ..

ALL of this is ballpark, but fairly safe..

Remember volts add in series.. Amps in parallel..

you can have as many LED in series on ONE LDD as long as 1)you pick the correct mA for the diode and 2)you don't run out of cumulative v(f)'s (> power supply voltage-3)..

Opp's misread your thread you have only 2,2,1 per "puck"..i'm not rewriting this.. I see no problem, and doesn't really change anything except halving the math BUT I'm not sure about running one diode on an LDD..esp. if it is low in V(f)

If you start w/ 2 it is the same as my one example..INSTEAD of a max of 3 you will max, at least one channel, out after 6 "spots"....

 

[CMJones]

So... i dont need restrictors/resistors or specific parallel and series runs... that sounds far too easy for there not to be a catch... its really just plug and play? And itll do the match to not allow over cooking leds since i won't even have nearly enough for that LDD to max? Wow... this does sound perfect for my build plan... now i need to determine colors i want when finalized and make sure this power supply has the amperage to cover the voltage for the final product... planning at the very minimum 36CW 36RB and 12UV on a 72inch x 18inch... want at least 6 inches on the two far ends to have reduced light so i can have a small dark spot.

Im actually kind of curious how it know how much power to allow through so not to blow the led... i thought the ldd controlled by how much power goes into it... and i have no clue how to bring the 48v of the power supply down to control a lower v on the LDD... but if thats not needed. Makes things a lot simpler

 

[perkint]

If I was running the 5W Cree XT-E at 1amp, doesn't that pretty much tell you it'll be pushing 3.2 to 3.6 Watts?

Sorry - yeah, it does. Knee jerk reaction from me as soon as someone starts talking about LED wattage recommendations

As far as the cree bulbs go, I haven't really seen anyplace that specifies what bins they are out of. Even on the cree website, they don't mention anything about bins and quality. I'm sure bulbs that come from across the western pond will be less quality than say, rapidled, but do the cree bulbs really have that much difference in quality like other brands?
I really appreciate the advice! I wondered about running different colors, but then I'd need a driver for each color wouldn't I?

There are places that show the bins and others places will tell if you ask. It really can make a big difference and is in every cree data sheet. This is a useful too for seeing how much difference it can make:
http://pct.cree.com/dt/index.html

For the tank, i wouldn't buy if i didn't know the bin.

You don't *need* to run different colours on different strings unless the are different drive currents. But it does give you control over the colour balance which can help a lot! And LDDs are pretty cheap

Tim

 

[perkint]

Right now im having a similar problem... i know the ELN/PLN drivers, but nothing about PSU and LDD. Here's what i got going on...

Looking at making just 2-3 "spot lights" for now to target 3 specific corals. Eventually in the future i plan to upgrade this as i can by adding more "spot lights" until the entire tank is lit with LED as i get more money. So, from what ive seen, LDD and PSU is the way to go... for the spot light im looking at right now. To make each one i plan on

2 cree CW XP-G2 (1500mah)
2 cree RB XT-E (1500mah)
1 semiLED UV (750 mah)

Each color on a separate driver and dismantle with POT

So, for 2 spot lights.
4 CW
4 RB
2 UV

1 LDD 700
2 LDD 1000

Power supply im looking at http://www.invertersupply.com/media/data/DV480.pdf

So, how do i wire this ans work it so that i dont burn the leds out until i get more of them to run full strings? And then... how do i run said strings?

Oreo57 has answered a lot of your questions, so I'll just comment on the "dismantle with POT" bit (i assume you mean dim?). You can't directly use a pot to dim an LDD (at least, not the LDD-H) as they need PWM dimming. Easiest way to achieve pot dimming is to simply use an arduino nano to read what your pots are set to and set the PWM accordingly for each channel. Very simple code and an arduino nano is dirt cheap

Tim

 

[CMJones]

Ok, i'll have to check that out then... Hrm, That makes me wonder, because the other lights i'm working on right now aren't aquarium related, but i DID just get 6 XM-L2 for my living room lighting. Wiring it to the previous wall switch i have which is a dimmer / switch as well. Wonder if the HLG i'm using for driver will work with that. Doesn't say pot would work, but resistance which is what i'm hoping this thing is...

Back to aquarium, so i understood that correctly that i feed the LDD with full 48W from a channel? Or do i put all 3 LDD on the SAME single channel and run the lights off each of those LDD? And Then the Amperage / Wattage will feed all off it to those LDD's which will then "auto" direct to the LED's the correct amount of power? If it is that simple and i'm understanding it correctly awesome. Just... really does seem too simple and i'm missing something here.

 

[perkint]

Not sure about the HLG (some of the combined PSU & drivers like the HLG, ELN, etc come in different models where the dimming control is by using variable input voltage (ie a pot/variable resistor) or by PWM). But the LDDs are brilliant and simple.

The LDD will start out by feeding out a very low voltage and checking the current. If the current is not at its rated output, it increases the voltage a bit and checks again. It then repeats this process until it gets to its rated output current, unless it hits its maximum possible output voltage (ie input voltage less 3 or 4 volts which get lost during the voltage regulation within the LDD itself). Oh, it does this check between 40,000 and 1,000,000 times a second

Each LDD should run a single string of whatever LEDs you want in that string, from one LED (so long as that one has a fV of at least 2V) up to the max fV the LDD can handle on the PSU you have (max an LDD-H can handle is 56V in, 52V out. Max for an LDD-L is 36V in 32V out).

Hope that helps, as i don't really understand what you mean by "i feed the LDD with full 48W from a channel? Or do i put all 3 LDD on the SAME single channel and run the lights off each of those LDD".

Tim

 

[perkint]

Ok, i'll have to check that out then... Hrm, That makes me wonder, because the other lights i'm working on right now aren't aquarium related, but i DID just get 6 XM-L2 for my living room lighting. Wiring it to the previous wall switch i have which is a dimmer / switch as well. Wonder if the HLG i'm using for driver will work with that. Doesn't say pot would work, but resistance which is what i'm hoping this thing is...

Re-reading this bit worries me. I have very little idea of how domestic wiring is handled over your side of the pond, but i don't think that'll work! I would assume the dimmer switch would actually be varying the 120V AC fed into the HLG. How are you wiring it?

Tim

 

[CMJones]

The way i'll be doing it is

Electrical from house (120V) to the HLG, from the HLG to the dimmer (wiring as usual for dimmer connected to driver), then to the LED's. Maxing out the HLG with 60V @ 3A (6 XM-L2 run on a string) for the house bit. Or, would i need a different dimmer and if so, what would work for this purpose? Or am i supposed to wire it from House to the Dimmer from dimmer to the HLG and then to the LED from HLG (i don't have the actual parts yet, so i haven't had the chance to sit down and look at the diagrams on them and how they're set up. They've been ordered and on the way in mail).

For the tank bit, from what i was to understand is that the PSU i was getting would be able to handle 4 LDD that can support roughly 12 LED of the type i was looking at at max power. So, that would be 12 RB / 12 CW / 12 UV / 12 more CW. Then i'd get another PSU to run the other 24 RB / 12 CW and 12 UV that would give me the full project when completed... But like i said, going to be doing it 2RB/2CW/1 UV at a time... Just wanted to make sure i wasn't blowing the LED's up by over powering them before i had "enough" on a single string. The biggest problem kind of is what order do i wire? I'll have a "bread box" for 4 LDD to plug into so i don't have to solder. So, House power to PSU, PSU to "bread box" then from each channel on the "bread box" to the LED's correct? And i should just be able to plug and play at that point? Is that more clear and that's what i'm understanding properly? If i wasn't using the "bread box". What i was wondering, since i've never used the PSU before. Is if it had a single port for each of the 4 LDD's that i'd be using, or is it just one single out that i would wire the LDD's in a string. Then run my string of LED's from the LDD? Or is it a single out from the PSU that i would split into 4 LDD's separately.

 

[Kaiserman1967]

Basically 3 "pucks" worth for one CW channel.
Same for WW.

Once the first is built, your done.. The LDD will control the voltage so to speak.. First only allowing 14.4V (concentrate on just one channel for now, the others will be similar)

to reach the 4 diodes. When you build the next you just cut the neg and run it to the pos of the next set of 4. now the LDD will "allow" 28.8V.

adding the 3rd puck and you get 43.2V

You now ran out of voltage..


adding another chain of 3 in parallel.. 5.4A ..

ALL of this is ballpark, but fairly safe..

Remember volts add in series.. Amps in parallel..

Opp's misread your thread you have only 2,2,1 per "puck"..i'm not rewriting this.. I see no problem, and doesn't really change anything except halving the math BUT I'm not sure about running one diode on an LDD..esp. if it is low in V(f)

If you start w/ 2 it is the same as my one example..INSTEAD of a max of 3 you will max, at least one channel, out after 6 "spots"....

Two questions about this comment.
1) What is a puck?
2) What do you mean by this "If you start w/ 2 it is the same as my one example..INSTEAD of a max of 3 you will max, at least one channel, out after 6 "spots"...."?

Thanks for all you guys' answers!! I've really learned a lot since building my first LED and seeing how far off I was was! Although it is still in use. http://www.reefcentral.com/forums/images/smilies/smileyshot2.gif

 

[Kaiserman1967]

It really can make a big difference and is in every cree data sheet. This is a useful too for seeing how much difference it can make:
http://pct.cree.com/dt/index.html

For the tank, i wouldn't buy if i didn't know the bin.

Tim

Tim,
I was looking at the site you provided, but I don't see (or understand) where the bin codes are for the LEDs. Also, what bin codes would you recommend, or is it more a matter of being from the SAME bin?

Lou

 

[perkint]

Looks like you need the HLG-B type, so, assuming that is what you have? You need to supply it a dimming signal of either variable voltage (0-10V) or 0-10V PWM. So your dimmer might work, but your gonna need a 10V PSU to connect it to, as just connecting the +ve and -ve from the HLG will do nothing as that is a dimming signal in (+ve) and reference gnd (-ve should be tied into the -ve from the 10V PSU) so the HLG can actually tell what signal it is getting.

Tim

 

[CMJones]

Its not a powered dimmer. Its similar to a pot. Resistance dimmer. It just restricts the amoint of power going out. So, i probably need a new dimmer for it? If so, ive got no clue what my options might even be. Ive tried online searches for 10v pwm dinners and couldn't find anything. Then the ones i DID find i asked a guy about and he said they werent made for that kind of setup, but some specific strand led set. Was actually wanting one with a remote control, but no clue what im actually looking for

 

[perkint]

Personally I'd think you could run 3 sets on that PSU, but it would depend to an extent on the actual fVs of the LEDs at the drive current. Using Oreo57s method of simply using the LDD rated current (which is a simple and decent method with builtin "erring on the side of caution" rather than an accurate method which i prefer) you could run 9 LDDs in parallel at 8.1A which is fairly hot for a 10A supply, but not frighteningly high if it is a decent PSU.

And then yeah, add 3 LDDs (all LDDs, however many, are connected in parallel to the PSU be that in parallel from one connection, or utilising multiple connections from the PSU) and run your 2,2,1 puck from it and keep adding until you reach 12,12,6 on that string. Then add another 3 LDDs and do the same. Then you can do it a third time. After that, you will be taking a chance to try a fourth string, so look to a new PSU

Hope that helps!

Tim

 

[perkint]

Its not a powered dimmer. Its similar to a pot. Resistance dimmer. It just restricts the amoint of power going out. So, i probably need a new dimmer for it? If so, ive got no clue what my options might even be. Ive tried online searches for 10v pwm dinners and couldn't find anything. Then the ones i DID find i asked a guy about and he said they werent made for that kind of setup, but some specific strand led set. Was actually wanting one with a remote control, but no clue what im actually looking for

Remote control is getting complicated!

But, all you need is a resistance dimmer. And a 10V PSU. Connect the 10V PSU to the dimmer and, assuming the dimmer you have works fine for your 10V DC feed...

Tim

 

[oreo57]

For the tank bit, from what i was to understand is that the PSU i was getting would be able to handle 4 LDD that can support roughly 12 LED of the type i was looking at at max power. So, that would be 12 RB / 12 CW / 12 UV / 12 more CW. Then i'd get another PSU to run the other 24 RB / 12 CW and 12 UV that would give me the full project when completed...

Err no, A 48v 15a (720W) power supply at minimum will run (as an example and simplifying to one driver "type")

15 LDD-1000's with 12 @ 3.6V diodes in series on each...
(12x 15x3.6= 648W..........)
180 LED's.. total..

Actually "doing the math" w/ each string and different drivers (say 700mA) could increase that "load"..

Just get a "storm" or Typhon for dimming.. both are "relatively" cheap in the scheme of your build..PWM 5V dimming easy peezy..

So... i dont need restrictors/resistors or specific parallel and series runs... that sounds far too easy for there not to be a catch.

nope and not catch..

Wiring it to the previous wall switch i have which is a dimmer / switch as well. Wonder if the HLG i'm using for driver will work with that. Doesn't say pot would work, but resistance which is what i'm hoping this thing is...

EEK.. no.... EVEN If (Iand I doubt it is) is simple resistance it would be feeding 120AC to the driver.. NOT a good idea.
most house dimmers are a triac based I believe.. Like this.. Ignore 220v

 

[CMJones]

Hrm, ill have to see how its wired in the wall. Hopefully it works.

On the psu, thats what i had hoped and why i was looking at it. I'll have it way under powered, but the price they have it at ($25) i couldn't pass it up. i only plan on about 108 led total. 12 of those being 700mah

 

[perkint]

Err no, A 48v 15a (720W) power supply at minimum will run (as an example and simplifying to one driver "type")

Did i read the wrong link? The one i followed was a 48V 10A?

Tim

 

[CMJones]

Its a 48V 10A.

 

[oreo57]

Its a 48V 10A.

Opp's pulled the "peak current" number my bad.........

OK 10LDD's x 12 X 3.6

120 diodes 432W....

JUST seeing if you are paying attention.........

36CW 36RB and 12UV

84

 

[CMJones]

Heh, alrighty. So, tank lights good to go then. Just wanted to make sure i understood all of that... now to figure out the house *lol* just hope that switch i have works. If not, i'll have to see if i can bug a housing forum to figure it out heh