Voltage drop is defined as the amount of voltage loss that occurs through all or part of a circuit due to impedance.
Excessive voltage drop in a circuit can cause lights to flicker or burn dimly, heaters to heat poorly, and motors to run hotter than normal and burn out.
Formula to calculate voltage drop.
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The resistivity value at 25 Celsius degree °C is 0.017 for copper and 0.0265 for aluminum.
Example:
Calculate the voltage drop of a copper wire of length 10 units , if the current passing through it is 20A , and its cross section area is 5 Square units.
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Therefore, the voltage drop is 0.68 Volts.