A three-phase motor located 300 Ft from the power source. The conductors supplying power to the motor is 3/0 AWG copper. The motor full-load current is 60A. What is the voltage drop across the conductors when the motor is in operation?

Answer 1

To calculate the voltage drop across the conductors, we can use the formula:

Voltage Drop = (2 * Length * Current * Resistance) / (1000 * Cross-sectional Area)

Where:
Length = Distance from power source to motor = 300 ft
Current = Full-load current of the motor = 60 A
Resistance = Resistance value per 1000 ft of 3/0 AWG copper wire = 0.0490 Ω (obtained from wire size chart)
Cross-sectional Area = Area of 3/0 AWG copper wire = 0.1678 in² (obtained from wire size chart)

Now, let's calculate the voltage drop:

Voltage Drop = (2 * 300 * 60 * 0.0490) / (1000 * 0.1678)
Voltage Drop = 17.94 V

Therefore, the voltage drop across the conductors when the motor is in operation is approximately 17.94 volts.