LED Lighting - Technical help!!

[Paul]

After some pointers to make sure I'm not going mad....

Calling

@Nedreud
@lukewells
And other Similar tecchies..

So - Picked up some Freebie LED lights, just needed to pick up a controller and remote...
So since i have two 5m lengths of RGB i picked up, dual controller (12v in, r/g/b out), and instead of being rated at 4A per colour, it;s only rated at 2A... not enough for two strings....

However thought i would crack it open and take a look anyhow...





So there are three 13N03LA (specs attached)power transistors, which as far as i can tell from the specs can drive up to 40A...
So - They are being driven by the rest of the cct which is just a trigger (on/off - takes next to no current and doesnt change dependant - so why couldnt i draw 6A from each?!!?!
The only reason i can see is because of the cabling... that can be easily rectified!!

In fact, looking at the bottom of the board, the 12v is permanently connected to the output, so it'll be a comparative voltage will probably control the lights... i.e.
12v 12v = no light,
12v 0v = full light

Almost like a switched neutral/negative type thing...

Any thoughts chaps before I shove lots of amps through it and see if it'll work

Paul

 

[Paul]

Common anode - thats it something like this...

 

[Nedreud]

Hi Paul, as you point the transistors are man enough for the job. They'll handle 30A up to 25V. At first I suspected the limitation in the overall circuit might be the surface mount current limiting resistors, in the middle marked 471. But these look as though they're connected to the Pin 1 (the gate) so aren't part of the power circuit for the LEDs, just the control signal. And thinking about it those strips of LEDs usually have the current limiting resistors built-in (mine do) so that there's the right resistance regardless of what length you trim it down to. The 78L05 is only a 100mA 5V regulator for the logic ICs.

I'd be tempted to get it out of it's stuffy little box, man up the output wiring and you're good to go. Obviously don't try running 30A per channel, but if your strips are 4-6A I think you'll be fine. The main thing is to make sure whatever 12V PSU you plug in to power it can deliver the juice. No piddly little 500mA Radio Shack multi-voltage adapters please

 

[Paul]

Oh it'll be connected to 2x VERY large leisure batteries

Thx for the second opinion @Nedreud

 

[Nedreud]

Leisure batteries? Code for car batteries that don't live in a car. Probably more like truck batteries. Cable of delivery WAY more current at 12V than anything you can plug into the mains Should be able to crank out 120A for at least 10 seconds!