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Old 03-15-2009, 11:26 PM
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cityevader cityevader is offline
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Join Date: May 2008
Location: Santa Cruiz, CA
Posts: 170
Default Re: 12 volt fog lamp as headlight

Originally Posted by Prasinos View Post
so im trying to move to leds and i burned out the first set of 4. Has anyone put enough capacitors on the bike to actually measure the voltage coming off of a motor? i was hooking up two pairs series wired 3.5 volt leds, so unless i did something seriously wrong, the peak voltage should be greater than 8 volts according to the tolerance ranges. So is there something i don't know about leds or does my engine put out more than 7.5 volts like the manual sais?
I used to be smart enough to tell you what you need. But like Norman said, the output is AC voltage, not DC. This is why lights flicker because it actually turns on and off very rapidly as voltage reverses polarity. And LEDs are polarity sensitive, and intolerant of overcurrent. 6 volts would be max capacity. You'd need a diode wired in series to prevent reverse polarity as well as a resistor in series to drop the voltage down. The exact resistor value is.....shoot, where is that formula?
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