300 LED Build

[Hans Dorn]

Short them by connecting them together?

Exactly.

 

How to max them if shorting works

 

-Dave

Just leave them open (disconnected)

[d9hp]

Short them by connecting them together?

 

How to max them if shorting works

 

-Dave

 

Yes, that's how to short them.

 

Max is just leave them untouched / open / unconnected / just sitting there useless.

[doctaq]

then if that works just connect a pot between the two dim wires to dim

[DaveFason]

I know cant wait to leave work

 

For adjusting, what type of POT should I look for?

 

-Dave

[d9hp]

I know cant wait to leave work

 

For adjusting, what type of POT should I look for?

 

-Dave

 

Well that depends on how high you want to run these things. I honestly think a 10kΩ may work just fine but I would be concerned with not having very much resolution down on the lower end. So you turn it just a tiny tiny bit and it changes the output like 25-50%. I think they make multiturn 10k that would work. I said 1k earlier but I thought about needing a bit more resistance to run them at full blast (open circuiting the ADJ)

 

Let me look for something.

 

EDIT:

 

http://search.digikey.com/scripts/DkSearch...me=SP534-10K-ND

 

That's ideal but it's outrageous! $13 trim pot?! That's nuts.

 

Note the 3600˚ rotation though! Talk about resolution!

[d9hp]

$3 cheaper:

http://search.digikey.com/scripts/DkSearch...3590S-2-103L-ND

 

Still not really ideal.

[nibor]

You could wire a toggle switch in series with the pot. Flick the switch to the "no dimming" position to open the circuit and let it run full blast.

[DaveFason]

Ok I am back!

 

After testing I still have the same thing. Nada. When I hooked my multi-meter to the LED outputs on the HLG and it wont read anything? When I had the wires off it read a solid 42v.

 

Bad soldering but it was a quick fix to see if this would work.

 

I tried with no pot and shorting them and still nothing.

 

After inspecting the strings I found two DOA's also. The odd thing is I tested them with a LPC-700 in a series and they still fire. I thought that they would not fire if in a series. The first one is the first in the series and the other is the second. Hmmm

 

Any other thoughts? I swear I'm about to go with a bunch of LPC drivers!

 

-Dave

[d9hp]

After testing I still have the same thing. Nada. When I hooked my multi-meter to the LED outputs on the HLG and it wont read anything? When I had the wires off it read a solid 42v.

 

After inspecting the strings I found two DOA's also. The odd thing is I tested them with a LPC-700 in a series and they still fire. I thought that they would not fire if in a series. The first one is the first in the series and the other is the second. Hmmm

 

You mean the V+ and V- lines are reading 0V?

 

When you fire them up with the LPC the dead LEDs are firing or the rest of the string works fine?

 

If they are dead due to a short, they would fire just fine though normally failures result in opens.

 

Hmm. This is tough. I definitely want to see this thing fire!

 

Can you tell me what V+ V- read and what ADJ+ and ADJ- are (voltages) when you try and fire the system. And what all is happening at that point?

 

Does it flicker or anything?

 

Can you disconnect the LED strings and fire up the driver? It should definitely output 42V at that point. Can you check the fuses again?

 

-Dustin

[redfishsc]

The situation is definitely beyond my area of knowledge.

 

 

At a glance though...... if the HLG is giving you a full 42v with no load (just like the 60-48's do) but it won't fire the LEDs, is it possible that your parallel strands are over the voltage rating?

 

 

In other words, how many LEDs do you have in each string? At 42v output, you should be able (theoretically) to run 11-12 LEDs per string, and however many total strings you want to divide up the current.

 

 

If you have 12 LEDs per string (or more) then it's possible that the HLG isn't capable of putting out enough voltage, and it just senses the overload and shuts down.

 

 

Keep in mind an LPC is a 48v driver, not a 42v, so it will light up a string of 12 LEDs just fine.

 

 

 

I noticed earlier in your post that your wiring schematic showed 6 LEDs. I don't know if that's actually how you have it wired up or if 6 was just a convenient number, but if you are running 6, make sure that the HLG can deliver that LOW of a voltage.

[Hans Dorn]

It's 11 LEDs per string I guess. Should be OK with 42V...

[Zeadon]

read post #46

 

ok that explains the 1.5" between the leds in each cluster, but im talking about why you chose to leave several inches between each cluster of leds.

 

rather than spreading them evenly across the entire span of the fixture?

[DaveFason]

I have 9 strings with 11 LED's each.

 

So I now have the following.

16 gauge wires from my driver to the terminals, then the fuses, then resistors and then 24 gauge from the terminals to the LED's. They are now only around 5' from the terminals to LED's.

 

When I had the drivers wires disconnected from the terminals I could get a solid reading of 42v ( dead on ). When I tried to hook the multimeter to the same spot with the wires connected to the terminals I did not get a reading? Should I try an test it on the resistor and see what I get? Am I testing it on the wrong spot?

 

I am now keeping the adjusting wires disconnected. I found that I need a much more adjustable pot to get it to work correctly. The data sheet it says keeping the ADJ wires disconnected it is 100% and shorting them is ~50%. This still had no effect on getting them to fire.

 

After trying multiple things I went back to test the strings of LED's with a Meanwell LPC-700. I two strings with one LED that would not fire and the rest were fine. The odd thing is the series of LED's will still fire even with the one not working. I thought if one LED in the series did not work they all would not work.

First string : D = Dead G = Good

D-G-G-G-G-G-G-G-G-G-G

Second String :

G-D-G-G-G-G-G-G-G-G-G

Could the two LED's that wont fire change anything? Of course I'll be swapping them out.

 

If it came down to it is there a problem running a high number of LPC drivers like there is with the ELN? I need to finish this VERY soon and if I have to I may have to run a high number of LPC's ONLY if it is safe.

 

Thanks again guys.

 

-Dave

[DaveFason]

All the fuses are good to go too.

 

-Dave

[Hans Dorn]

How many of the HLG did you hook up when you tested?

[DaveFason]

Just one.

 

-Dave

[Hans Dorn]

Try another one, at minimum output.

 

Maybe the one you tested didn't like the 9V connected to the adj pins.

[evilc66]

Dave, LEDs have two failure modes; open and closed. Open is the one that we come across most often, and will kill the entire string. Closed failures is a short across the diode (rather than the bond wires breaking), keeping the LED from working, but still completing the circuit.

[DaveFason]

Clive - Thanks for the break down.

 

I will try another driver. My mind is melting.

 

If I HAVE to would running a high number Of LPC drivers be ok?

 

-Dave

[evilc66]

Tough to say. The LPC drivers don't list the PFC, so you can't tell what the inrush current is for each driver.

[blasterman]

Maybe the one you tested didn't like the 9V connected to the adj pins.

 

I was waiting for somebody else to mention it, but it was my concern as well.

[DaveFason]

Just tried a different driver. Nothing still.

 

Argh!

[d9hp]

Dave,

 

Remove the two strings with the burned (shorted) LEDs in them. Even at full blast it would only be about 700mA through the remaining 7 strings. This shouldn't be an issue.

 

I don't imagine this will help but SOMETHING isn't working when all these things are being fired simultaneously but work fine individually. It HAS to be something. The driver doesn't sound like it's the issue.

 

Have you tried that?

 

-Dustin

[d9hp]

When I had the drivers wires disconnected from the terminals I could get a solid reading of 42v ( dead on ). When I tried to hook the multimeter to the same spot with the wires connected to the terminals I did not get a reading?

 

When you say you did not get a reading, do you mean you got 0V? This is an important part of the resolution.

 

Also, how are these LEDs mounted? Have you tested the two 'non-functioning' LEDs for continuity with the heatsink? Just put the probe on the heatsink and on both solder joints. You could just measure the resistance (Ω on the meter) and if it's <100Ω or so that's an issue.

[DaveFason]

I think I need to trade you frags to come help me this Sunday

 

-Dave