How to wire automotive LEDs, and which LED for brakes

FredM

Enlightened
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Mar 7, 2005
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666
Location
Houston, TX
I need to rewire my farm trailer and was thinking of using LEDs. The reason is these trailers are always breaking their lights because of livestock breaking them directly and from the fact that much work is done around them.

I was wondering:

In my experience autos have around 12.5V when shutoff and 13.8 volts when running. How do I wire the LEDs to use this? 4 LEDs in series? DO i need a driver? There has to be a common solution.

I would like to go with red/orange LED incase i break the lens so I was wondering where can I buy the high output version I need? I would prefer to buy bright ones like a Rebel or something.

Can a aluminum disk provide the needed heatsinking? Has anyone ever done this totally custom? I do not know how I am supposed to have brake lights brighter than tail lights.
 
I think you should look for some dedicated LED trailer lights. I think that would be much easier.
 
probably much more expensive though. I have a lathe so can make my own heatsinks. The only real cost would be emitters.
 
It will be easier and less costly to buy ready-made LED lamps for your trailer. The other advantage is that the end result will be street legal.
 
Try taking a look at whelen.com

Specifically the TIR3 and LIN3, I have the TIR3 on the back of my motorcycle and they are quite bright and solid.
 
I need to rewire my farm trailer and was thinking of using LEDs. The reason is these trailers are always breaking their lights because of livestock breaking them directly and from the fact that much work is done around them.

Maybe if you started out with readymade truck/tractor lights and built a wire or plexi cage for each one to keep the stock off it? Or can you countersink them into the frame? You can form plexi by cutting a piece, putting it in the oven, heat to around 400 degrees, sqeeze into a form when you pull it out.

DO i need a driver? There has to be a common solution.

The thing to watch for is to protect them from being overdriven.

Can a aluminum disk provide the needed heatsinking?

Yes.

Has anyone ever done this totally custom?

Yes.

I do not know how I am supposed to have brake lights brighter than tail lights.

Twice as many LEDs light up?
 
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to get different brightness either adjust the output of the driver to less or put a resistor on the parking light input so it is dimmer while the brake lights are full power.
 
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