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Q & A: wiring for bulbs

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Most recent answer: 06/21/2013
I have a motorcycle 78 with a 6V battery. I purchased a set of tail light only to find out it has 12V bulb..My Question. If I switch out the 12V bulb to 6V, and left the original wire. Will Everything be OK?
- Michael (age 23)
Long Beach, CA, LA

It might not be. For a particular brightness of standard bulb, you'll need some particular power, say 6 W for example. Since power=current*voltage, you need higher current for the low-voltage bulb. In that example it would use 1 A, instead of 0.5 A for the the 12V bulb. It's possible that the wires will have trouble handling the higher current and might overheat, although they may well have enough extra capacity to handle it. If you can find a bright enough 6V LED bulb that fits, it will have such high efficiency that its current draw will be even lower than the 12 V regular bulb.

Mike W. 

(published on 06/21/2013)

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