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Old 07-30-2009, 02:38 PM   #2 (permalink)
JacobAziza
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Quote:
Originally Posted by Piwoslaw View Post
My question is: Should I put a resistor and/or diode in series with the relay coil? If so, what kind? Would the current be too big without a resistor?
Depends on the rating of the relay you get.

I have a "generic 12v auto relay" still in the package, its only 30A, which should be more than enough for a 55w headlight (30A x 12v = 360W) without a resistor. (unless standard headlight and relay ratings are different in...um...where ever you are)

Although I am not sure that it'll work in parallel, as it won't get full current and might not be enough to close the relay. On the other hand, in series it might dim the headlight, so...
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