I'm not understanding something very basic here.(adsbygoogle = window.adsbygoogle || []).push({});

I know what voltage drop is. At least I thought I did.

Here is a question:

Assume you have a power supply in a control panel of a building. 500 feet away is the load device. When doing voltage drop calculations for the wire (500 feet each way) am I to add up the sum of the voltage drop along all 1000 feet of wire - or just 500 feet? All the voltage drop calculators and formulas I have seen only ask you for the distance from the power supply to the load (1/2 the total wire length). Then they go on to say how the voltage drop of the wire is calculated on that distance only (power supply to load device). What I am not understanding is what about the voltage drop on the return wire (the other 500 feet). Why is that voltage drop not included in the total voltage drop of the circuit? Or is it?

Lee

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# Voltage Drop Question - Building Wiring

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