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Discussion Starter #1 (Edited)
1. Is it possible to "fry" or ruin an LED light by running too much current or amperage through it, or connecting it backwards? [YES!]

2. If you cut off the small transformer box and wires from this "120v/AC" light, doesn't it become 12v/DC compatible? (that's what I did)
[YES, BUT WITH CAVEAT!]

I was 90% done with a set of 10 overhead LED round reccessed lights, and they had tested to work fine, but now I'm totally stuck!

I had already installed the wiring, ceiling panels, and had in 9 of my 10 lights. They worked. I thought that my 10th was just a dud. I ordered a replacement. But today when I turned on everything and hooked up the wiring to my 12v aux battery (there was a 100A fuse in between, basically meaningless here) There was some flickering, some lights came on fully, and now they all don't work.

However, I know that there is power (and ground) at each of the locations where I have lights, this was confirmed via a multimeter and by actually turning on an LED light strip I had on hand.



I had previously helped a friend with a conversion where we used some 12v LED circular ceiling lights - made by "Lighting Ever". They were great, and I wanted to do the same thing on my current conversion. The prior models weren't for sale any longer, so I bought these off Amazon and then cut off the little transformer/adapter box and assumed that Red=POS+ and Black=Neg-



Anyone have any ideas?
 

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LED lights are diodes so connecting them backwards positive to negative will mean they simply will not light. Are you sure you have wired them in parallel not in series? That is all the positive wires need to go back to the battery and not to the next bulb.
The transformer says 13 volts so they should work. Caution to other posters to buy lights intended for 12 volts unless you want to experiment. Many experiments end in failure so we know what doesn’t work.
 

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Some LED'S will burn out if the polarity is reversed (I know from past experiments) but as RD says, most just will not work. I have many LED strip lights from IKEA that run off a 110 vac power supply. I simply cut the low voltage plug off and wired them directly to my 12 vac house batteries after determining the polarity of the wires and they always have worked fine. I've discovered that some LED's I've bought don't even care about polarity and will work no mater how you connect them and keep in mind not all LED's are dimmable (although any I've bought from IKEA are.

Here is a good link that might shed some light (sorry) on LED's for you. http://led.linear1.org/category/led-basics/

And a good source for LED lighting https://www.superbrightleds.com/cat/led-strips-and-bars/
 

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Discussion Starter #4 (Edited)
My LED lights are wired in parallel (all the pos+ branch off from a single long wire, and all the Neg(-) connect to a single long wire)

It definitely sounds like it's easy to run too much current through LEDs and destroy them - I guess that's what I did.

I'm just baffled about why this is NOT happening with the prior models I used https://www.amazon.com/1-5-Inch-Lighting-Equivalent-Under-Cabinet-Downlight/dp/B00LE5J2BI/ref=pd_rhf_se_p_img_9?_encoding=UTF8&psc=1&refRID=DNHJTYSEM1DSMK6FNH6J#Ask

But it IS happening with my new ones: https://www.amazon.com/INHDBOX-Recessed-Ceiling-Downlight-3000-3500K/dp/B01FVRQVK4/ref=sr_1_3?ie=UTF8&qid=1492871743&sr=8-3&keywords=inhdbox+LED


Is everyone else wiring a resistor onto their LED lights or using an LED driver to limit the voltage and current?
 

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His LED driver output specifically says 13 VDC shouldn't t be a problem.
 

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The power supply says 13V but the description says 3 volts. If there is not a special wiring harness to feed these (series & parallel harness) then it looks like some are duds. I would suggest contacting the seller.

Also, I would try to connect 12V to one light that works, and one that doesn't to see how they behave when not part of a combined set. If I had bought these, I would have wired them the same way VanGuy did, based on the power supply labeling. The red and black (+ and -) are critical for most LEDs.
 

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His LED driver output specifically says 13 VDC shouldn't t be a problem.
Not trying to be nit picky, but the LED Driver says OutputDC 3 - 13V300ma. The only way to know for sure what it is really putting out is to put a small load on it and measure it with a meter. Probably without a load the voltage will be close to 13, but when you connect the LED, the voltage will drop way down.
 

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But he's not using the driver. It only supplies the voltage the lights need to work from AC by converting the AC to DC. He is only using 12 VDC. The only important thing is what voltage the lights were/are actually designed to run on (most likely maximum of 12-14 VDC as the driver is rated at 3-13 volts) I still think he simply has one bad light.

As I've stated before, I've used many of these LED's that all run off 110 VAC with a DC driver but actually run on straight 12 VDC with no problems at all. I've always connected several together in parallel on a single switch with no problems. Revering polarity is the biggest concern with this kind of light but even then I've bought many 12 VDC LED bulbs at automotive flea markets that simply have two leads on them and work without any regard to polarity at all.
 

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Discussion Starter #13
I definitely don't simply have one or 2 bd LEDs. I now tested them all using a 9v battery and they are basically are fried. I was running to much current, too many volts, or both.

Now I've got the two strings (6 lights, and 4 lights) each separate and I've got access to the "-" & "+" supply to each, so I'm looking to install an LED driver to limit the current (and/or voltage) to each strand.

Any suggestions or advice on a model of LED driver?

I'm still not really confident that the numbers listed on my built-in AC Driver (3-13v, 300mA) are what I need to use to calculate the 12v DC demands of the LEDs. I've emailed and called the manufacturer and retailer, with no reply.
 

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I suggest you cut your loss and trash them. Don't waste your time and money on this brand anymore. You should have no problem finding 12 VDC LED's online that will just work on 12 volts. You shouldn't need any kind of external driver at all - they should just work on 12 volts if that's what they are sold as. You should also be able to connect as many as you wish (in parallel) with no problems.

The link I posted a few days ago has many, many types and styles of LEDs and they are also available all over the web. It may very well be the ones you bought are not really 12 volt but the driver you have is only for running them from 110 VAC you shouldn't even need a driver to run them on 12 volts it should be built in or the LEDs should add up to 12 volts.

Sometimes things just don't work out as expected and then it's time to move on!

Good luck, you will solve your problem by going with another product.
 

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I'm dredging this thread looking for a little bit of similar but not identical help.

I have 8 of these.

I am trying to run them through this.

Wiring all checks out, at least in that the USB and cigarette lighter thingy will both charge any device I've tried. And each of the three switches on that plate are backlit (indicating that they are hot) and when I test them with my multimeter they do have juice.

But I can't get the LED lights to work. They have black and white leads, and white is ground. No problem, I've wired them accordingly, but they still won't light up.

Anyone care to point out the obvious that I must be missing?

Eventually I'll run 2 on one switch, 2 on the middle switch, and 4 on the third switch. But right now I can't even get one of them to light up.

Thanks in advance.
 

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Remember LEDs are diodes and will allow current (and light up) if the DC polarity is correct. Have you tried reversing polarity on one of the lights? It should light in one polarity and do nothing in the other. In my experience reversing polarity does not damage them but I’d test only one light just in case.
 

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Remember LEDs are diodes and will allow current (and light up) if the DC polarity is correct. Have you tried reversing polarity on one of the lights? It should light in one polarity and do nothing in the other. In my experience reversing polarity does not damage them but I’d test only one light just in case.
After reading this thread I did reverse polarity and still got nada. I've tried three lights now -- first properly wired, and then reversed. No light at all, regardless.
 

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Have you tried connecting them directly to a battery? I guess I would contact the seller.

RD is correct about the polarity but I did once burn a 12v LED out by reversing the polarity by mistake. Having said that, I have a lot of 12v LED's in my van (all from IKEA designed to run off 110 VAC). I simply cut off the plugs to the AC drivers, double checked the polarity and wired them directly into a 12 VDC circuit thru a mini 12 VDC switch. Every one has worked flawlessly. The last time I was at IKEA I did notice most of their LED lights now seem to be 24 VDC rather than 12 VDC, unfortunately for us.
 
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