Why are the power lines on the poles so small in gauge but for example my 200 amp service has a much thicker wire going into the panel. ?
In: Engineering
You spec the gauge of wires based on the current they will carry and you spec the insulation based on the voltage (and environment). The higher the current, the thicker the wire and the higher the voltage, the thicker the insulation.
Ohm’s Law tells us that there is an inverse relationship between voltage and current for the same power. If you double voltage (again, for the same power), you halve the current.
The lines going from pole transformer to pole transformer are going to be in the 7-14-ish kilovolt range. This means that for a 24 kW load at 7.2 kV, you’d only be drawing about 3.3A. However, for the service drop from the pole transformer to the house, that same 24 kW load would require 200A.
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