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What is the formula for calculating the voltage drop across the cable?

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βˆ™ 2010-06-01 15:12:29

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The formula for a simple DC voltage drop across a cable is:

VDrop = Vmeasured at the input of cable - Vmeasured at the output of cable

This formula may seem simplistic however keep in mind that the sensitivity, accuracy and resolution of measuring instrument instrument is what is really important.

If you know the DC current flowing through the cable and the impedance of the cable then you can use Ohm's law. Vdrop = I R where Vdrop is the voltage drop across the cable in volts I is the current flowing through the cable in amperes R is the resistance of the cable in ohms.


Calculation of the voltage drop is given by the formula below

Voltage Drop (Volt) = [(mV/Am)/1000] * I * l

Where mV/Am = millivolt drop per meter per ampere of the cable

(this information is given in the table based on IEE Wiring Regulation)

I = Current in the cable (in Ampere)

l = Distance of cable (in Metre)

See related links below

2010-06-01 15:12:29
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