TN LLE Motors and Motor Circuits 2

Question 1

Per NEC Table 430.248, what is the full-load current of a 5 HP, single-phase, 230V motor?

Accepted Answer

28 amperes

Answer

NEC Table 430.248 lists the full-load current of a 5 HP, single-phase, 230V motor at 28 amperes.

Question 2

Per NEC 430.22, what is the minimum conductor ampacity for a single motor branch circuit?

Accepted Answer

125% of motor FLC

Answer

NEC 430.22(A) requires branch-circuit conductors supplying a single motor to have an ampacity of not less than 125% of the motor full-load current from the applicable table.

Question 3

What is the maximum size inverse-time circuit breaker permitted for branch-circuit protection of a single-phase motor per NEC 430.52?

Accepted Answer

250% of FLC

Answer

NEC Table 430.52 permits inverse-time circuit breakers up to 250% of the motor FLC for standard motor branch-circuit short-circuit and ground-fault protection.

Question 4

Per NEC 430.32, what is the maximum overload protection for a motor with a service factor of 1.15 or greater?

Accepted Answer

125% of nameplate current

Answer

NEC 430.32(A)(1) limits overload protection to 125% of the motor nameplate full-load current for motors with a service factor of 1.15 or greater.

Question 5

Per NEC 430.102, a motor disconnecting means must be located where relative to the motor?

Accepted Answer

Within sight from the motor location and the controller

Answer

NEC 430.102(A) and (B) require the motor disconnect to be within sight from the controller location, and 430.102(B) requires a disconnect within sight from the motor.

TN LLE - Tennessee Limited Licensed Electrician Practice Test

TN LLE - Tennessee Limited Licensed Electrician Practice Test

TN LLE Motors and Motor Circuits 2