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Led driver

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Electriceye

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So I finally recieved, this LED driver.

I still hope to put my own together one day with resistors and voltage regulators and such...however I took the easy way out to get my project up quicker.

Soo do I go ahead attach white wireson this to standard 120v ? Does it matter which side goes to the polarized end ?

Also, can I only wire this to 3 LEDS ? Only utilizing it 30% ? Or will this overvolt my leds ?

View attachment 68738
 
Why are your leds connected in parallel?

I dont see any white wires?

It looks like 120V line goes to the two blue wires .

Red goes to anode of the first LED.

Blk goes to the cathode of the last LED, the three LEDs should be wired in series.

Why did you start a new thread when you already have one running on exactly the same topic???
 
Last edited:
Okay thanks, im concerned with which wire to go to the polarized end on my extension cord.


Thanks very much for pointing out that I am running these in parralell, I totally forgot!

Well, now I gotta go back to drawing board
 
Sure, as long as they are both rated for an If of 670mA. By the way, if you run 670mA through those leds without bolting them to a large heatsink, you will vaporize them.
 
Yeah all my leds are 700ma, but some use different VFS.

Thanks for the fair warning, and again about noticing my my parralel.

So far ive only seen my leds wired in parralel to a 0.7a 5.5V cell charger 2 leds of them how come they didnt vaporized if "1400ma" were supposto run thru them ?
 
The vaporizing comment is based on heat dissipation in high-power LEDs. Read the data sheet for the LEDs. At 3.4V @ .67A, the LED is dissipating 2.3W, so the LED needs a heat sink, meaning that it must be bolted to a fairly large chunk of aluminum, steel, or copper, not just left dangling on a couple of wires....
 
GOT it.

I am curious though to know exactly what is going on here, how many ma's are my LEDS running at in this scenario.

Power : 5.5V .7A LED 2x paralell: 2.6VF 700ma

This means that the LED only wants 2.6V but 1400mA right ? or

What happens ?
 
The power supply you bought is a constant-current driver. It will drive 670mA through whatever you connect out there (up to its compliance voltage). LEDs are intended to be driven with a constant-current (NOT DRIVEN WITH VOLTAGE), the forward voltage across the LED will be whatever it will be.

In your case if you hook up thee LEDs in series, the same current (670mA) flows in all the LEDs. If you mix different colors, the forward drop across the various LEDs will be different with each color. Even if you connected several LEDs of the same color in series, then there will be variations in the forward voltages. The forward voltage of any given LED changes with temperature of the chip, too.
 
GOT it.

I am curious though to know exactly what is going on here, how many ma's are my LEDS running at in this scenario.

Power : 5.5V .7A LED 2x paralell: 2.6VF 700ma

This means that the LED only wants 2.6V but 1400mA right ? or

What happens ?

Likely, you blow up the power supply (you grossly overloaded it), or the LEDs (no current limiting).

This connection indicates that you do not have a clue about what you are doing.
 
Okay so im a little scared now. I wired 10 3.6v 700ma devices to this power driver.

When I powered on, they were flashing and I heard a noise coming from the driver i think !?

Whats going on here ?
 
Depending on the architecture of the power supply, it's possible that it's going into a hiccup mode due to a short in your wiring. When a typical constant current driver detects an over current situation, it kills its output so the current ramps down and waits a fixed amount of time before turning back on again where the cycle will continue until the fault is cleared. This is done to prevent the power supply from self destructing. I would verify that none of your wiring going to the pads of the LEDs are shorted to the metal circuit board underneath.

The noise you hear is probably due to the magnetostriction of the inductor in the power supply. When a magnetic field is applied to an iron inductor core, the magnetic fields of its atoms align causing a very small elongation of the core. When the frequency of the magnetic field is in the audible range, you can hear it. This is the same reason why many transformers hum.
 
Thanks phalanx, perhaps that may be the case due to a poor soldering job/wire size too big. It makes sense.

I'll re wire the whole thing with smaller wire/less solder.
 
Okay im a little confused to be honest about this LED driver. Ive re-soldered them, using LED legs instead of wire (theyr thinner) easier to work with, 10 RED 2.6-2.8vf 700Ma devices in series. It failed to turn on, however there was a faint noise coming from driver.

When I tried again with 9 devices, half of them lit up, and blinked and made noise.

What am I doing wrong ? ? Does this driver need an exact amount of LEDS connnected to it to reach its "voltage" ? Ive tried so many variations now. View attachment 69198
 
Ive done 10x 3.6v LEDS, 10x and 9x 2.6-2.8LEDS ... cant find a winning combination here. View attachment 69199

Please help, im having a major electrical meltdown here...so much devices..so little time for holidays to get this all together!
 
Since the great hard drive crash of 2012 wiped out some posts in this thread, I'll have to repeat one of my responses.

I remember from your pictures that your wiring was incorrect. Each LED should only have 1 wire going in and 1 wire going out. The red output wire of your power supply should connect to the first "+" pad on the LED. The "-" pad of the first LED is then connected to the "+" pad of the second LED. This pattern repeats until you get to your last LED where its "-" pad is connected to the black output wire of your power supply.

As an example, here is a picture from one of my projects where if you look closely, you can see that each LED only has 1 wire in and 1 wire out:
**broken link removed**

And more pictures of the project:
**broken link removed**
**broken link removed**
 
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