Question

The voltage drop percentage for a panel feeder with a noncontinuous load of 180A, using 3/0 THWN copper conductors at 480V, three-phase, and a length of 248' is a. 1.23% b. 1.28% c. 1.42% d. 2.03%

Answer 1

To find the voltage drop percentage for a panel feeder with a noncontinuous load, use the formula Voltage Drop Percentage = (Voltage Drop / Voltage Supply)× 100. Calculate the voltage drop using Ohm's Law, then substitute the values into the formula to find the percentage.

Step-by-step explanation:

The voltage drop percentage for a panel feeder with a noncontinuous load can be calculated using Ohm's Law and the formula:

Voltage Drop Percentage = (Voltage Drop / Voltage Supply) ×100

First, calculate the voltage drop:

Voltage Drop = (Current × Length × Resistance) / 1000

Given: Current = 180A, Length = 248', Resistance = Resistance of 3/0 THWN copper conductor

Resistance values for copper conductors can be found in NEC Table 9.

Once the voltage drop is calculated, substitute the values into the formula to find the voltage drop percentage.