Question

Which of the following list full load currents for three phase motors with a known winding type, horsepower, and voltage

A) 50HP, 460V, Wye-Delta winding - 60 A
B) 20HP, 230V, Delta winding - 50 A
C) 30HP, 575V, Wye winding - 40 A
D) 10HP, 480V, Delta winding - 15 A"

Answer 1

The correct answer is A) 50HP, 460V, Wye-Delta winding - 60 A.

Step-by-step explanation:

The correct answer is A) 50HP, 460V, Wye-Delta winding - 60 A.

For a three-phase motor with a known winding type, horsepower, and voltage, we can use the formula I = (sqrt(3) * P) / (V * EFF), where I is the full load current, P is the power in HP, V is the voltage, and EFF is the efficiency of the motor. In this case, for option A, we have:

I = (sqrt(3) * 50) / (460 * EFF)

If we assume an efficiency of 90% for the motor, we can calculate the full load current:

I = (sqrt(3) * 50) / (460 * 0.9) = 60 A

Therefore, the correct answer is A) 50HP, 460V, Wye-Delta winding - 60 A.