LED buckpuck vs drivers

[TheFishMan65]

I don't think that is true if I remember what I read. The royal blues give almost the same amount of PAR IIRC. Someone (taqpol maybe) did a par study and the royal blue had almost as much par as cool whites I think they compared XR-E to XR-E.

[EDIT]
Yes taqpol, go down to post 73

 

[AngelAddict]

Oh Well, I know I've read That the XP-G are a lot stronger then the XR-E and a 40/60 is 14k, I want more blue so I went with 35/65. Regardless I needed to order more. But I'm excited, just dropped $23 0 on little LEDs but Hopefully it will be well worth it! I'm just really scared about soldering and messing one up. Maybe I should have ordered extra? Oh well too late now. Now I need to finalize my driver, wire, solder, solder station and heatsink size (thinking 12x12).

 

[g8gxp]

The blue is actually the more important one. your 2:1 ratio of blue to white is good though. I have mine at 1:1 and to get the color i want i run the whites at 30% and the blues at 70%.

 

[AngelAddict]

Sounds good to me, I'd love to run the lights at 100%, I probably will until I hook up the dimming feature.

So it sounds like I should get the ELN-60-48D meanwell drivers right? I'm about to order them now. What size heat sink should I use for 37 LEDs? The tank is a 20" cube. I think I'm also going to order 6 blue 6 white XR-Es and make a practice light for my 24g AP before I make the bigger light.

 

[stugray]

Laverda,

"have run two strings of 14 in parallel on the ELN-60-48D with out any problem. Granted I have not run them for weeks, months, or years yet. "

WHICH Leds are you running like this?

Stu

 

[AngelAddict]

Ugh the more I read, the more discouraged I get. I honestly do feel like I'm in over my head! I don't know how to wire up this pot or testing with the meter! I think there's just too much info/too many different ways, if things were clear cut and dry it'd be a lot easier. My mind needs a break, I really want to learn this and accomplish making this light, so I'll study some more later!! I need a"how to understand and build an LED light for dummies" book!

 

[Zimster]

What areas in wiring and testing are you having trouble with?? We all should be able to help you make it a little more clear cut.

 

[AngelAddict]

Well the only thing I have ordered is my LEDs so far, I still need to get a lot of equipment. The biggest question I have left to order is the pot. Where do I get it and What one? Once I get everything, I will have tons of questions on what to do! I'm more of a visual learner, pictures are truly worth a 1000 words. I've been bookmarking every helpful page. I understand the pot,but don't know exactly how to wire it up. Also I don't know What I'll need to test before using my light, I know I'll news to put it in series at the end of my string,but the whole adjusting to 700-1000MA and fine tuning everything is still a bit beyond me. Thanks for the help, I appreciate everyone's time.

 

[HeneryH]

The voltage and current adjustment pots are internal to the ELN. You just take the covers off, turn then both down to 0, power it up, then adjust the pots to get you your desired Vf and I.

For the dimmer, I would just start with a 9v battery. You can get 9v batt clips at RatShack real cheap. I got everything working first with the 9V then moved on to the dimmer controller. Remember though if using a 9v to tune current accordingly.

 

[HeneryH]

For tuning, you want to calculate your max brightness current. The diagram below is for the ELN-60-24 parallel but ELN-60-48 serial is very similar. Serial is even more simple. Just choose the highest current you want to run through the string.

For that current, look up the forward voltage for your specific LEDs. The pic shows the curves for the Cree XPG and XPE LEDs.

Set your V accordingly choosing the Vf * the number of LEDs in serial.

For instance, XPG running at 833mA is about 3.2v. I run 7 LEDs in each string so my V is set to 22.4v

 

[g8gxp]

don't worry, I was as confused as you were when i started. I know jack sh** about electronics but was able to get it all done. Once you get the parts in and can physically see what people are talking about it will make much more sense. When you can open the driver and actually see what is being described and the wires you have to manipulate, solder, etc.etc. it will fall into place.

 

[AngelAddict]

Hen, thanks for the pics. I don't want to use the 9v battery even temporarily, I want to get it right the first time and be done with it. So if I am understanding this right, the driver has a certain V and I. I hook up a pot to this line and dial the driver down to zero (or dial down first then hook up the pot, if it matters). Then I adjust V and I with the pot? So how do I actually dim the lights? What do I want to have for V and I? The ELN-60-48 is 1000MA so dial it to about 900MA which is roughly 3.3v and at 12 leds thats 49.2v but how do I run 13/14 XP-Gs on a single strand? I'd have to dial the current down to about 500MA according to that chart?

g8gxp, yeah I really need to get the driver and pot infront of me. I hope it all works out, I not only want to make this light, but understand what I am doing and exactly is going on, how it works etc.


So what pot should I buy? Can someone please provide a link so I can order it and get a better idea of what I am dealing with? Thanks!

 

[HeneryH]

AngelAddict,

Regarding the pots and how to adjust:
The adjustment pots are built into the ELN, you just get a small screwdriver and adjust them on the board. You don't need to buy anything. (Unless you are talking about a pot to tune down your 10v dimmer source maybe. btw a pot is short for potentiometer which is just an adjustable resistor.)

Dial both down, power up and set your dimmer to +10v. Set your voltage by adjusting the internal pot up until the voltage gets to your desired value (we'll talk calculating it next).

You'll need to pop off a wire now to get your meter serially in-line with the driver to measure current. Ramp the current to the desired value.

Done.

Regarding the calculation:
If your max-current target is 1A which is the max of the driver (and a good starting point if you ask me). The resulting Vf is about 3.3v. Taking the available 48v/3.3v = 14.545454. Round down and you can get 14 LEDs in the string running at 1A. You'd then set your Vf to 3.3v * 14 = 46.2v.


Innards of the driver:

The pots are shown below next to the V and I text overlays. They are hard to see but they are just plastic philips screw adjustments.

 

[AngelAddict]

Whoops for some reason I was thinking 40v not 48v. OK well it makes sense for the most part, bit I really need to see it to understand it. I will get the drive (ELN-60-48) but what else do I need to make it dimmable? A potentiometer? What else? Where can I get one? I'll buy it now so I can understand this better. Thanks for taking the time and patience to explain this to me.

 

[AngelAddict]

What's arduino and what is it used for?

 

[TheFishMan65]

An arduino is a microcontroller that can be used to dim the drivers to simulate dawn and dusk. It can also do things (with even more extra hardware) to measure temperature, keep track of time, measure PH, etc.

Dimming for now a potentiometer and a 10V regulated power supply. Unless you are ordering electrical parts from non specialty stops it probably no worth shipping just get the potentiometer at radio shack IMHO.

 

[HeneryH]

What's arduino and what is it used for?

It is a DIY computer board and development kit for people who want to make their own DIY controller. Think of an Apex or RKE slapped together with bare circuit boards, duct tape and wire-nuts

just kidding guys... they can look pretty


edit - whoops sorry, duplicate answer. didn't see the response on the next page before I posted.

 

[AngelAddict]

Sounds good, I may look into one later but for now I'll Just get the potentiometer and a 10v wallwart and call it a day. Just pick that up at radioshack? I was trying to avoid that place!

 

[TheFishMan65]

I tend to avoid it too, but sometimes because of shipping it is cheaper if you only one or two items. But you do need to watch the quality Make sure the 10V is regulated.

 

[AngelAddict]

The wallwart has to be regulated, will it say that on it?