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Ralph Mowery Ralph Mowery is offline
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Default Power cable thickness q:


"John Smith" wrote in message
...
What kind of cable should I use to connect seven 50 W light. The cable
draw power
from a 10A supply.

One thing I do not understand is that I have to use pretty thick wire but
table
lamps have thin cables. What's the story here?


The size of the wire will depend on how far your lights are from the power
source.

In simple terms there are low voltage/high current circuits and high
voltage/low current circuits. The larger the current , the bigger the wire
will need to be to carry the same ammount of power. If the wire is not big
enough or too long for the size , the voltage will drop in the wire and the
light will not be as bright.

A 50 watt light operating on 120 volts will take about .4 amps and you can
run small wire a long distance. The same light operating on 12 volts will
about 4 amps. That is a 10 times differance so the wire will need to be
much larger.