Commercial grade LED voltage question

[Robbie]

So I just cleaned out a box of old sample crap from my work that has been under my desk for years and in there I found a few LED light fixtures from HERA. There is 1 puck light (3 LED), 2 long flexible stick lights, and 1 shorter rigid stick light. HERA makes great lights and their quality is very high! So I'm hoping I can use these in the trailer. I have 2 transformers with them also. Now I'm guessing that the transformer is to convert the 100-120 AC current down to 12V DC current? On the pigtail of the transformers where the lights plug into it says 6-24VDC max. 3A. Now I'm assuming this means you can plug anything DC that has a voltage of 6-24 volts, correct? I've looked all over the lights and no voltage rating. Only 0.35A current and 1Wx3 LED. And HERA's website doesn't have this info listed... That I could see anyway.

Does anyone know if I could wire these lights directly to my 12v system and use them in my benroy? Of course they would be wired through the fuse block. What size fuse to use? And could I run them all on the same circuit?

Robbie

*Here is a link to the puck light fixture...
http://www.lbutampa.com/Lighting-Fixtur ... -0LFS0-WW/

[LWW]

I'm at that point on my build for lights to and I'd be interested in this also. I even thought I might buy one and cut the transformer off and put 12v to it to see what happens. Larryw

[Robbie]

Ya I think I'm gonna try that with this one. I figure it was free and if it doesn't go in the trailer I probably wouldn't use it anyway. I would have to cut the connector off to wire it into my system anyways. I just don't know which lead is + and which one is -. One wire has a red stripe on it, I'm guessing for the hot or + lead?

[Forrest747]

the red stripe is positive, take a pair of 9 volt batteries and connect one set of terminals together and then tough the wires on the pucks. will give you 18v plus verify which wire is the positive.

[Robbie]

Hmm. Connect them together + to + and - to -? Or opposite? I forget which way will double the voltage. I was also thinking of just disconnecting my car battery terminals and touching the ends of the wire to the terminal tops. Is that a bad idea?

[GuitarPhotog]

the red stripe is positive, take a pair of 9 volt batteries and connect one set of terminals together and then tough the wires on the pucks. will give you 18v plus verify which wire is the positive.

Hooking five 9 V batteries together in series like that gets you 45 V, not 18, and exceeds the input rating of the LEDs. You can blow out the current limiting circuit in the LEDs by exceeding the rated input voltage by that much. javascript:emoticon(':oops:')

Your LEDs draw 0.35A of current, which at 12V is 4.2 watts.

You can hook your LEDs to your 12 V teardrop battery, but the one thing Forest got right is that you'll have to figure out which is the positive wire on the LEDs.

<Chas>

[Robbie]

Ok thats some good news. Could I just use a single 9V battery to determine which wire is for sure the positive? Is that enough voltage to get some light output if its right?

[Forrest747]

Yeah the 5 batteries like that will give you 45 volts. Its the only picture I could find on google that explained my thoughts. Just 2 will do it. We also used the neighborhood kid to see if the batteries were any good. Just lick them my son told him. He hasn't been over to the house since we saw him crying and running from the house I used one battery to just get a dim reading to see if they work and what positive wire was which.

[bdosborn]

Can you get a voltmeter and check the output voltage of the transformer? Its pretty easy to build a power supply for the LED using a chip like this:

12V Power Supply

Bruce

[jb]

i'm building my teardrop with 2 led spots. i don't use the transformator but just some wires from my 12v teardrop battery. and to see whats + or - : just try. mine didn't break when i did it wrong and when i changes the + and - my leds light up
the positive thing about using led in your caravan is that is don't use a lot of energy and mosquito's don't come for this kind of light. the reason is that there is no UV in led lights