Bridge rectifier wiring

[greg g]

I understand you can up grade lighting on snow blowers by using automotive type L E D auxiliary lamps.

I also understand that the wire that feeds my current dim lamp provides 10 to 14 volts of AC current.  Apparently LEDs don't like AC, and they flicker with the cycles.  Several sources say to put in a bridge rectifier to change the AC to DC.  I have looked at several schematics but I guess I am being more dense than usual.  There is a single wire coming out of the engine (5HP Tecumseh) most of the schematics show AC going into the recitifier from 2 sources, with one out put of DC to power the light.  I don't see where the other AC lead comes from.  

 

Can any body provide me with a simple schematic and some basic understanding of how to wire one up?

[TodFitch]

Wild a** guess: The metal in your snow blower is the other leg of the AC.

 

If so, then I think you might have a common ground issue if you use nothing more than a bridge rectifier as you are likely to want to have one side of the DC grounded too. If you put an isolation transformer on the input then you can have common grounds for both the AC and DC.

 

Probably just be easier to put in quartz-halogen bulbs.

[Ulu]

Yes, the wire from the generator goes to the (+) input of the rectifier. The other input wire of the rectifier (-) goes to a metal ground, but instead I'd run a separate ground wire from the body of the generator to the (-) input of the rectifier. And isolate the lights completely. Don't ground the lights, but use two wires from the output of the rectifier to each lamp.

 

Output polarization doesn't matter to normal lamps if they're not grounded, but some LEDs do need to be polarized and some do not. Look at the directions with the LED.

 

I use several 12v LEDs to light my aquariums, and you want to keep the water out of them. Some sealant on the housings might help.

 

Look up "wheatstone bridge full wave rectifier" for a diagram of what's inside the rectifier. It's just 4 diodes in a diamond pattern.

Edited December 23, 2014 by Ulu

[oldodge41]

Check this out Greg. 

http://www.snowblowerforum.com/forum/general-snowblower-discussion/6602-upgrading-your-snowblower-lights-led-lights.html