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Christmas Lights Run 250 feet from house to a tree near road. There is an outlet. Extension cord. Split to many extension cords then split to many lights. Also split after first EC to a few extension cords going to two wreathes. The lights are LEDs and it says 90 stands take less than 2 amps. We have had amp issues before but want to know if the distance of extension cord itself takes amps? Or does it just supply the one/two amps?
 

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Christmas Lights Run 250 feet from house to a tree near road. There is an outlet. Extension cord. Split to many extension cords then split to many lights. Also split after first EC to a few extension cords going to two wreathes. The lights are LEDs and it says 90 stands take less than 2 amps. We have had amp issues before but want to know if the distance of extension cord itself takes amps? Or does it just supply the one/two amps?
There will be a small loss of Volts not amps,
( Lower volts make amps rise )
But if you use a good size cord (thick as poss')
and if the load is low, like only 2 amps
then the loss will be very small
not enough to worry too much about.
 

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There will be a small loss of Volts not amps,
( Lower volts make amps rise )
Only for a motor load, because motors are weird. Resistive loads like lights, heaters, and almost everything else follow Ohm's law: I=V/R. Lower voltage results in lower current.
 
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Just to give you an idea of how minimal the voltage loss is with LEDs.

1000 ft of #16 wire (typical light duty extension cord) has about 2.5 ohms of resistance. So 2 amps of current would result in 2 * 2.5 = 5 volts lost in the resistance of the extension cord, leaving a nominal 120 - 5 = 115 Volts available to the LEDs.
 

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I think the general concensis is -
Running a load of 2 amps over 250 ft
will not be a problem.

The only time it becomes a problem is with bigger loads,
So if your getting up around 10 amps or so,
A thicker power lead would be required.

A good rule of thumb is for long runs of cable
you should double the current rating,
So instead of using a cord rated for 10 amps
use a cord rated at 20 amps.

And to be technially correct leads dont eat up amps,
instead they eat up volts.
 
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