LED'S ARE THE BEST!!!!!!!!!

[2quills]

Quote:
Originally Posted by Monsinour http:///forum/thread/386777/led-s-are-the-best/40#post_3404031
My house is over 100 years old and I am sure the wiring is all original. I wouldnt do 12 PCs with accessories on one circut in a new house. 2 circuts would be fine and each PC would be plugged into an APC BackUPS office 450 or so. In the corporate offices that I have worked in, the floors were divided into 4 circuts and each one had around 30 PCs with accessories on them. The only exception to this was the DataCenter on the 13th floor at a former employer. That floor had 25 circuts and each one in the data center powered around 4 servers. There may have been some cases where one circut powered more and I know there was one dedicated circut to run the PeopleSoft server. At the time it was the most advanced server ever built. Compaq, back when they were compaq and not HP, built the server special for our company. It was the first 8 way xeon processor server. It was a monster of a box and was lighting fast. Once peoplesoft was loaded on it, it came to a crawl, LOL. I am sure they were better quality than what we might in our homes, but with line conditioners on the PCs etal., it doesnt effect the power wiring that much. BTW, keep any kind of electrial motors off of the same surge strip as a PC (the fan mentioned) as the motor will create interference with the PC and networking cabling regardless of the shielding. The APC units will ensure a regulated draw from the outlet and will condition the noise (THD) before putting it back onto the house wiring as well as condition the noise going to the PCs. In the suggestion mentioned, think of the APC UPS as a filter to keep the 'noise' out of the equation. Even a cheap $45 unit would do as you dont really need the battery power.
Cool. So it sounds as tho an APC UPS is and acts essentially as a harmonic filter would. Definitely sounds to me like a must have when running multiple non linear switch mode power supplies. And that's exactly what those dimmable ELN drivers are. I mean surely a small hand full of them wouldn't be detrimental. But logic and common sense leads some to believe that you really should be careful when throwing a bunch of these things into a DIY build.
I'm with Shawn on the idea of why really go through the extra trouble of purchasing an extra device to make them safe when better options are out there. And that's really what we were trying to point out to 242bats here. I could build a fixture and utilize 10 eln drivers and spend extra money to compensate for the harmonics for safety concerns and equipment protection. Or I could spent the same or less money and build a fixture with the same amount of LED's using only 2 drivers with the harmonic protection (power factor correction) already built in. Not only that but they are more efficient drivers as well and also more flexible in terms of dimming options. You're dealing with 2 power cords to plug in instead of 10, and about 32 extra positive, negative and dimming wires to deal with in the fixture. less weight, less heat, less supplies needed, more room. Just makes more sense.

 

[scsinet]

Quote:
Originally Posted by Monsinour http:///forum/thread/386777/led-s-are-the-best/40#post_3403742
r u saying that these drivers dont opperate at 60 hz?
What he is talking about is the difference between real power and apparent power. The topic gets into advanced AC theory. Basically it means that even though the drivers, being SMPS (SwitchMode Power Supplies), are rated to draw X amount of energy, but the actual load on the wiring and OCPDs in the panelboard are X+Y. In an SMPS without power factor correction (PFC), that has a power factor of say 0.7, you can multiply the draw of the power supply by the reciprocal of the power factor to get the actual current drawn.
So in the case of a 3 amp power supply, non PFC, with a (typical) power factor of 0.7...
PF Multipler = 1/pf, RECIPROCAL (0.7) = 1.429
3 * 1.429 = 4.287
Now, if you have a 15 amp circuit and you set up (4) of these power supplies, the nameplate says you'll be pulling 12 amps total. A meter on the circuit (at least most meters) will read 12 amps. However you're actually pulling 17.15 amps, thus overloading the circuit.
The capacitors sound good in theory, but there are several problems. 120v is the RMS line voltage, but capacitors have to be rated for peak-peak, For a 60hz sine wave, you've got 120*1.414 = 169v. First, a capacitor in the thousands of microfarads to farad range that is rated for at least 169v, and rated for AC would be very large and very expensive. Of course that is all moot because although you can apply AC to appropriately rated capacitors, you do not get AC out of them.
So from my reading, it sounds like our problem here primarily is inrush current, the surge that the main PSU filtering capacitors place on the line, when all power supplies are energized simultaneously. I see two ways around this problem.
1. Run several timers set a minute or so apart, then spread the power supplies out across them.
2. Place relays on the LED side of the power supplies, tie them to your timer, and run the power supplies continuously, avoiding inrush.
As far as harmonics go, it really isn't too big of a concern IMO. As has been fully pointed out by Monsinour, these drivers are not unlike computer PSUs. More and more household equipment uses switchmode power supplies. It is not at all uncommon anymore to have a half a dozen or more SMPS units operating off one circuit. A modern DVD player, flat panel television, cable box, etc all have them, so you've got a bunch right there in your living room.
If harmonics are going to be any problem it is going to be interference with GFIs or other nuisance stuff. Putting a decent filter such as an Tripp-Lite Isobar on the drivers should clear that up. Unless a UPS is a double-conversion UPS, it's just pulling straight through off the line with a crappy ferrite core filter whenever it's not in battery backup mode, so there isn't much filtering going on there. No consumer UPS is going to be double-conversion, you only see that in really big UPS units. As long as you figure the actual power drawn (as shown above) properly, and use that to figure your current draw, you'll be okay IMO.

 

[2quills]

Interesting, SCSInet.
So harmonic frequencies really wouldn't concern you here? I didn't figure it would be a major deal when only running a handfull of these things. But I've seen guys stacking up as many as 10-16 of these power supplies on one build. How these combine to create frequency above the fundamental 60hZ and on into the 2nd harmonic range is still a little bit confusing to me but I think I'm on the cusp of having a much better understanding.
Here is the data sheet for the ELN 60's. Specfically looking at the 60-48's that everyone is commonly using...http://www.meanwell.com/search/eln-60/eln-60-spec.pdf
Could you help me to understand how to figure how much frequency I would get in a round about way going by the data sheet alone without having to purchase a bunch and then throw my meter on there? Hypothetically lets say I wanted to run 10 of these drivers on the same circuit and had them split in half to fire up 5 at a time.
I just want to get this nailed down because it's been a big debate in the hobby. And some are saying the harmonics are a real issue for concern when having too much.
You're saying a tripp-lite bar with a filter would help?
Also, since these drivers have front end capacitors, would running them on a controler set to come on at 10% dimm help at all with the initial inrush current to charge the capacitors? According to the data sheet the inrush is a 60 amp draw per driver.
Would greatly appreciate your feedback on this.

 

[monsinour]

Stay away from Tripp lite stuff. It is complete and absolute garbage. I am not at all concerned with disparagement cases coming against me from tripp lite. I stand behind my statement that any and all tripp lite stuff is complete carp and you can find a better product that will do what hte tripp lite does in an APC unit and that APC unit will do a vastly superior job.

 

[janely]

Oh! My god! My favorite aquariums grow so slow ! What can i do now? please give me some advice ,thanks!

 

[prh123]

Depends on theme of tank, high flow, blue light, chemistry got my Coralline algae to grow red and green on the bottom, purple, pink, and lime green on the live rock in 8 hours, the experts told me three months it would turn to pink and purple. I got the 8 hours from the snail and hermit crab clean the bottom together, just white calcium buffer on the bottom in the morning, eight hours in today bright green and red coralline algae. No nitrates, phosphates, ideal magnesium, calcium, carbonate buffer. 20000K and Actinic 03 lights (blue/white) 4.2 watts per gallon, flow in surges up to 98X.

 

[prh123]

The worst part, mushrooms seemed to grow out of the tank with just the skimmer and a 50/50 and actinic 03 low level light 2.7 watts suspended 8 inches above the tank. (low level lights no surges or turbulence) thus the mention of a theme.

 

[scsinet]

Quote:
Originally Posted by 2Quills http:///forum/thread/386777/led-s-are-the-best/60#post_3404224
Interesting, SCSInet.
So harmonic frequencies really wouldn't concern you here? I didn't figure it would be a major deal when only running a handfull of these things. But I've seen guys stacking up as many as 10-16 of these power supplies on one build. How these combine to create frequency above the fundamental 60hZ and on into the 2nd harmonic range is still a little bit confusing to me but I think I'm on the cusp of having a much better understanding.
Here is the data sheet for the ELN 60's. Specfically looking at the 60-48's that everyone is commonly using...http://www.meanwell.com/search/eln-60/eln-60-spec.pdf
Could you help me to understand how to figure how much frequency I would get in a round about way going by the data sheet alone without having to purchase a bunch and then throw my meter on there? Hypothetically lets say I wanted to run 10 of these drivers on the same circuit and had them split in half to fire up 5 at a time.
I just want to get this nailed down because it's been a big debate in the hobby. And some are saying the harmonics are a real issue for concern when having too much.
You're saying a tripp-lite bar with a filter would help?
Also, since these drivers have front end capacitors, would running them on a controler set to come on at 10% dimm help at all with the initial inrush current to charge the capacitors? According to the data sheet the inrush is a 60 amp draw per driver.
Would greatly appreciate your feedback on this.
Harmonics wise, perhaps there is some aspect of this that I'm not seeing that explains why it is such a big debate. My recommendation for a line filter would prevent noise from the drivers getting back into the home's wiring. I'm not sure however how the drivers all operating together might impact each other, but I doubt very much because most SMPS systems have a rudimentary line filter on their input anyway.
I wonder how many folks are realizing just how much inefficiency they are dealing with by using all of those drivers... it's pretty much a universal truth in power generation and power supplies that one big one is more efficient than lots of smaller ones.
As far as dimming, it depends on where the dimming is done. If the dimming is done on the AC input side, that should help with the inrush. If it's done on the low voltage side with a low voltage control (such as 0-10V, DMX, etc) then no, it wouldn't. The 60A of inrush shouldn't hurt anything as long as it does not trip your breakers and your switching system is properly designed. What I'd be more worried about than the amount of current is the wear it's going to put on the contacts of any timer you have switching the whole thing. 600A of inrush is going to pit those contacts badly, that's why splitting them out across timers or using solid-state relays (rated for the inrush of course) might be a better way to go. Even though it's a 15A circuit, 600A of inrush lasting a few milliseconds is probably not going to be an issue.

 

[2quills]

Quote:
Originally Posted by SCSInet http:///forum/thread/386777/led-s-are-the-best/60#post_3404753
Harmonics wise, perhaps there is some aspect of this that I'm not seeing that explains why it is such a big debate. My recommendation for a line filter would prevent noise from the drivers getting back into the home's wiring. I'm not sure however how the drivers all operating together might impact each other, but I doubt very much because most SMPS systems have a rudimentary line filter on their input anyway.
I wonder how many folks are realizing just how much inefficiency they are dealing with by using all of those drivers... it's pretty much a universal truth in power generation and power supplies that one big one is more efficient than lots of smaller ones.
As far as dimming, it depends on where the dimming is done. If the dimming is done on the AC input side, that should help with the inrush. If it's done on the low voltage side with a low voltage control (such as 0-10V, DMX, etc) then no, it wouldn't. The 60A of inrush shouldn't hurt anything as long as it does not trip your breakers and your switching system is properly designed. What I'd be more worried about than the amount of current is the wear it's going to put on the contacts of any timer you have switching the whole thing. 600A of inrush is going to pit those contacts badly, that's why splitting them out across timers or using solid-state relays (rated for the inrush of course) might be a better way to go. Even though it's a 15A circuit, 600A of inrush lasting a few milliseconds is probably not going to be an issue.
Cool, thanks for the input. Harmonic wise, from what I was told and the way I understand how they work is that those drivers have diodes that charge front end capacitors. And that the capacitors pull power from the wall in tiny sporadic gulps. Basically they charge, then fire, charge then fire..etc. So the more you have, the more they build up and the more stressful it becomes. I'm not sure if that actually creates more distortion or not, maybe it just has more to do with current draw. I guess the only way to know for sure is to test a rig that's already been built.
Yeah that pretty much confirms my suspicions about a controller actually making anything safer. It's all done on the low voltage side of things and not on the a/c current coming into the drivers. So I've just been trying to figure out things people can do who have already built rigs utilizing all these drivers to help make them safer. It sounds like your recommendations would be to split the drivers across timers to fire a minimal amount of them at a time and or using solid state relays rated for inrush and installing a line filter for distortion would be some things people could do to help minimize stress on things.

 

[scsinet]

Quote:
Originally Posted by 2Quills http:///forum/thread/386777/led-s-are-the-best/60#post_3404769
Cool, thanks for the input. Harmonic wise, from what I was told and the way I understand how they work is that those drivers have diodes that charge front end capacitors. And that the capacitors pull power from the wall in tiny sporadic gulps. Basically they charge, then fire, charge then fire..etc. So the more you have, the more they build up and the more stressful it becomes. I'm not sure if that actually creates more distortion or not, maybe it just has more to do with current draw. I guess the only way to know for sure is to test a rig that's already been built.
If that's the case, then these things are unlike any SMPS I've ever seen. Nearly all switchmode supplies use the same input stage, it's only the output stage that changes. Although individual component values vary, the structure is the same. Manufactuers do not make their schematics public, so without having one of these in hand to tear about and eyeball to figure out the exact structure, I can't be sure. Regardless, here is a rundown of how an SMPS works in most cases...
Power enters the unit and passes through a line filter. It then goes through a set of diodes to rectify the AC to DC, and through a bank of filtering capacitors. What results is filtered DC power to run the rest of the supply. It is these capacitors that cause high current inrush.
However, the caps are not doing a "charge then fire." The capacitors charge fully at startup and almost never leave full charge until the supply loses power. The only time you'd see a "charge then fire" is on older SMPS designs that use a switch to toggle between 115 and 230v, something commonly found on old computer power supplies, but nothing modern uses that design anymore.
So... I don't understand how a rectifier/filter design, a design that has been out for decades, is going to cause these types of issues.

 

[2quills]

Quote:
Originally Posted by SCSInet http:///forum/thread/386777/led-s-are-the-best/60#post_3404928
If that's the case, then these things are unlike any SMPS I've ever seen. Nearly all switchmode supplies use the same input stage, it's only the output stage that changes. Although individual component values vary, the structure is the same. Manufactuers do not make their schematics public, so without having one of these in hand to tear about and eyeball to figure out the exact structure, I can't be sure. Regardless, here is a rundown of how an SMPS works in most cases...
Power enters the unit and passes through a line filter. It then goes through a set of diodes to rectify the AC to DC, and through a bank of filtering capacitors. What results is filtered DC power to run the rest of the supply. It is these capacitors that cause high current inrush.
However, the caps are not doing a "charge then fire." The capacitors charge fully at startup and almost never leave full charge until the supply loses power. The only time you'd see a "charge then fire" is on older SMPS designs that use a switch to toggle between 115 and 230v, something commonly found on old computer power supplies, but nothing modern uses that design anymore.
So... I don't understand how a rectifier/filter design, a design that has been out for decades, is going to cause these types of issues.
Correction. I was wrong in my thinking of the pulses being drawn from the main by the capacitors. It actually happens in the rectifying stage just before the capacitors.

Input rectifier stage
kground-position: initial initial; background-repeat: initial initial; ">

AC, half-wave and full-wave rectified signals.
If the SMPS has an AC input, then the first stage is to convert the input to DC. This is called rectification. The rectifier circuit can be configured as a voltage doubler by the addition of a switch operated either manually or automatically. This is a feature of larger supplies to permit operation from nominally 120 V or 240 V supplies. The rectifier produces an unregulated DC voltage which is then sent to a large filter capacitor. The current drawn from the mains supply by this rectifier circuit occurs in short pulses around the AC voltage peaks. These pulses have significant high frequency energy which reduces the power factor. Special control techniques can be employed by the following SMPS to force the average input current to follow the sinusoidal shape of the AC input voltage thus the designer should try correcting the power factor. An SMPS with a DC input does not require this stage. An SMPS designed for AC input can often be run from a DC supply (for 230 V AC this would be 330 V DC), as the DC passes through the rectifier stage unchanged. It's however advisable to consult the manual before trying this, though most supplies are quite capable of such operation even though nothing is mentioned in the documentation. However, this type of use may be harmful to the rectifier stage as it will only use half of diodes in the rectifier for the full load. This may result in overheating of these components, and cause them to fail prematurely. [sup][3][/sup]
So if that's true of SMPS's that do not use PFC that they can produce a significant high frequency. Then would I be wrong in thinking that the more you use, the higher the frequency could be?
Edit: I wanted to add here that there has been quite a number of folks who have tried to throw a kilowatt meter on their rigs built with the eln's. And the over all theme of what is being seen is that the readings are way higher than what they should be. I think the average is that guys are seeing their meters saying that the rigs are operating at twice the wattage of what they should be. And it's been suggested that it is due to the kilowatt meters inability to interpret the correct signal through the horrid harmonics being produced. And this has begged the question that if a K-O-W meter cannot read the fixture right, then what does that say about the houses meter at the main?

 

[scsinet]

I see what you are talking about, but I think confusion exists as to whether or not this is really a problem.
Consider the top (regular sine wave) and the bottom (full wave) that you posted.
If you take the bottom half of the original AC waves, and flip them over, that forms what you see in the full wave graph. That's all the rectifiers are doing, is taking the negative swing and flipping it over. In the end, from the wall outlet, the same AC waveform is being fed in.
There are two types of power supplies in this world that produce DC (well... two for all practical purposes), linear and switching.
Both of them, at different points in the circuit, do the exact same thing... rectify sine wave AC, filter it through capacitors, and put out DC. Linear supplies have been around for a hundred years, using tube rectifiers (and Tungar rectifiers before that) before silicon recifiers came to be... that's how far they go back. Practically everything in the home that uses electronics of any form uses this same sort of arrangement at one stage or another in it's power supply. Almost every wall-wart (wall adapter) uses it too.
Regardless, for the rest of your post you need to look back at my comments on real-vs-apparent power. KWH meters read current differently than multimeters or other devices such as the kill-o-watt. Manufacturers also usually rate their supplies by apparent rather than real power to make their specs look "more efficient."
In other words, I'd take exception with those that feel that their power supplies are "drawing more than they should." They are drawing exactly what they should when the power factor calculations are understood. They are drawing more than the nameplate says they should, but that's not because of the power supplies, it's because of misleading manufacturer ratings.
Now then, power factor calculations are normally not a big deal for most residential users because most things that have skewed power factor ratings are not present in sufficient draws and sufficient quantities in the home to make anyone care... lets face it, most people never even look at the nameplate specs on anything they have. In industry however, the discrepency between real and apparent power can amount to huge amounts of money lost. The difference between real power drawn and apparent power amounts to billed electricity that produces no work. In other words... wasted power.
As long as you know somewhere-abouts what the power factor is (in the absence of ratings, 0.7 will suffice), you can accurately calculate what your home's circuit is capable of carrying and what the supplies will actually draw, and make sure you don't go over, that's about the best you can do, or use power factor corrected supplies. PFC correction circuits tie into the supply, there isn't anything that can be slapped between the wall outlet and the plug to "fix" the issue externally.

 

[2quills]

Quote:
Originally Posted by SCSInet http:///forum/thread/386777/led-s-are-the-best/60#post_3405277
I see what you are talking about, but I think confusion exists as to whether or not this is really a problem.
Consider the top (regular sine wave) and the bottom (full wave) that you posted.
If you take the bottom half of the original AC waves, and flip them over, that forms what you see in the full wave graph. That's all the rectifiers are doing, is taking the negative swing and flipping it over. In the end, from the wall outlet, the same AC waveform is being fed in.
There are two types of power supplies in this world that produce DC (well... two for all practical purposes), linear and switching.
Both of them, at different points in the circuit, do the exact same thing... rectify sine wave AC, filter it through capacitors, and put out DC. Linear supplies have been around for a hundred years, using tube rectifiers (and Tungar rectifiers before that) before silicon recifiers came to be... that's how far they go back. Practically everything in the home that uses electronics of any form uses this same sort of arrangement at one stage or another in it's power supply. Almost every wall-wart (wall adapter) uses it too.
Regardless, for the rest of your post you need to look back at my comments on real-vs-apparent power. KWH meters read current differently than multimeters or other devices such as the kill-o-watt. Manufacturers also usually rate their supplies by apparent rather than real power to make their specs look "more efficient."
In other words, I'd take exception with those that feel that their power supplies are "drawing more than they should." They are drawing exactly what they should when the power factor calculations are understood. They are drawing more than the nameplate says they should, but that's not because of the power supplies, it's because of misleading manufacturer ratings.
Now then, power factor calculations are normally not a big deal for most residential users because most things that have skewed power factor ratings are not present in sufficient draws and sufficient quantities in the home to make anyone care... lets face it, most people never even look at the nameplate specs on anything they have. In industry however, the discrepency between real and apparent power can amount to huge amounts of money lost. The difference between real power drawn and apparent power amounts to billed electricity that produces no work. In other words... wasted power.
As long as you know somewhere-abouts what the power factor is (in the absence of ratings, 0.7 will suffice), you can accurately calculate what your home's circuit is capable of carrying and what the supplies will actually draw, and make sure you don't go over, that's about the best you can do, or use power factor corrected supplies. PFC correction circuits tie into the supply, there isn't anything that can be slapped between the wall outlet and the plug to "fix" the issue externally.
Correct, the confusion (at least for me) lies in whether or not it does or does not become a problem. And it could be because of my ability or inability to comprehend how frequencies interact with each other. Lower frequency signals produce a longer wave and higher signals are produced in a shorter/more frequent wave form.

And that's really my question, or what I'm trying to understand. The previously posted wave form was an example of a single SMPS. And what I'm trying to wrap my mind around is what happens when you start throwing more SMPS's on the same circuit, does that effect the wave form or would it stay the same? And if it did effect it, then at what point does it become sufficient enough to be problem? I would think there has to be a limit. Because when I read information from articles such as this http://www.cpccorp.com/harmonic.htm#What problems do harmonics create? it makes me wonder. But its like you said, with the absence of actual numbers then the best we could do really is make educated guesses without real world testing.
I could just be over thinking this whole thing. And if it wasn't for the fact that people who seemed to me more informed in these areas than I bringing it up then I probably would have never given it a second thought. I appreciate your input here and helping me figure it out.
Harmonics and Inrush current aside, I do hear what you're saying about actual and apparent power. I thought about that today and had wondered if what some of those guys with their kilowatt meters are actually seeing is not actually a result of harmonic frequencies distorting readings, but rather the result of the actual power being consumed by the leds and the drivers. It would be a myth to think that just because I build a fixture utilizing 100 - 3 watt leds that the fixture would actually only be using 300 watts max at peak power. The reality is, is that this simply just isn't the case. So I harken back to your question of whether or not folks realize just how inefficient builds utilizing a bunch of drivers actually is.
It would stand to reason that if I wanted to build a fixture and was only given lets say two ways to do it (even though there's more) and one being more efficient than the other, then which one would I chose? I could build a fixture that was going to use 120 led's. I could build it using 2 larger (higher efficiency) power supplies or I could also build it out of 10 smaller (less efficient) ones. Even though the larger driver utilizes a little more energy than a smaller driver on it's own, the shear number of smaller drivers vs a lower number of larger ones begins to actually work against one of the key factors that I was intending to build the fixture for. And that would be a more cost effective and energy efficient solution to say...running halides.
It's all in an effort to better understand the technology and help us move forward in the diy led revolution as safer and wiser individuals.

 

[242bats]

the new drivers just got here. looks like i got some work to do.
now if i am looking at this right, all i need to do is run my groups of the LED's that i have in series of 14 then 13 and so on and so on and then parallel the groups???

 

[2quills]

Remember that your parallel strings have to have an equal number on each string for the corresponding driver. So you can do strings of 13 on one driver and 14 on the other but you can't do both on the same driver. For simplicities sake, would you mind posting up the info again. Which leds exactly are you using and how many do you have of each color?

 

[acrylic51]

Agree what LEDs are you using???? Corey did you ever post up the thread from RC so he could read the way to test and balance his strings? I know you probably mentioned the utube video as well?

 

[242bats]

Quote:
Originally Posted by 2Quills http:///forum/thread/386777/led-s-are-the-best/60#post_3405384
Remember that your parallel strings have to have an equal number on each string for the corresponding driver. So you can do strings of 13 on one driver and 14 on the other but you can't do both on the same driver. For simplicities sake, would you mind posting up the info again. Which leds exactly are you using and how many do you have of each color?
the LEDs that i am running are XP-G R5 cool white and the XP-E royal blue there are 54 of each
thank for all the help
david

 

[2quills]

Well you have a couple of options.
Driver A.) 4 strings of 14 leds = 56
Driver B.) 4 strings of 13 leds = 52
Total = 108 leds But you'd have to move 4 of one color onto the other driver. I would move 4 blues to the driver for the whites since the xp-g's use less voltage.
Or
Driver A.) 4 strings of 13 leds = 52
Driver B.) 4 strings of 13 leds = 52
Total = 104 So you would have to drop 4 leds in this case.
Either way, I really wouldn't run more than 13 leds per string of the xp-e blues. Since they require slightly more voltage. Keep it at 13 on those and you should be fine. The xp-g's you can do strings of 14 safely since they require slightly less voltage.

 

[acrylic51]

On the money Corey...had to go back and look at my notes, what I had worked out on the XP-G's.....I'd personally opt for option 2 though.

 

[242bats]

Quote:
Originally Posted by 2Quills http:///forum/thread/386777/led-s-are-the-best/60#post_3405396
Well you have a couple of options.
Driver A.) 4 strings of 14 leds = 56
Driver B.) 4 strings of 13 leds = 52
Total = 108 leds But you'd have to move 4 of one color onto the other driver. I would move 4 blues to the driver for the whites since the xp-g's use less voltage.
Or
Driver A.) 4 strings of 13 leds = 52
Driver B.) 4 strings of 13 leds = 52
Total = 104 So you would have to drop 4 leds in this case.
Either way, I really wouldn't run more than 13 leds per string of the xp-e blues. Since they require slightly more voltage. Keep it at 13 on those and you should be fine. The xp-g's you can do strings of 14 safely since they require slightly less voltage.
i think i will go with the first option, just a bit of work to do but that is OK!!
there is one more thing about this new driver, there is not a way to make ajustment on the driver? is that output now ajusted at the controler only and not on the driver and the controler??
thanks
david