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What size resistor should I use to shorten a string of Christmas lights? Answered

I need to shorten a string of christmas lights from 20 lights to 3 lights.

The unaltered string ratings are  120volt,  .08 amps.

The bulbs/lamps are 6volt and .48 watts each.   It is interesting to me that 20 lights x 6volts = 120volts.
I'm sure that is not by coincidence but I'm not an engineer so I don't know how to use that information.

I need to know what size resistor I need to use.  This is way to confusing for me to follow.

If someone can help me out with a simple formula I would appreciate it as I need to work with
lights strings of many different lengths.  Please try and put your answer into laymens terms.




8 years ago

It's not coincidence, bulbs' voltage drop x number of bulbs. As for resistors, make a voltage divider, you can find a calculator here