EIAT and NEIEP Test Motor Controls

Question 1

What is the primary purpose of a magnetic motor starter?

Accepted Answer

To automatically start and stop a motor while providing overload protection

Answer

A magnetic motor starter combines a contactor for switching with an overload relay for protection, allowing automatic control of a motor.

Question 2

What does NEMA stand for in the context of motor controls?

Accepted Answer

National Electrical Manufacturers Association

Answer

NEMA stands for National Electrical Manufacturers Association, the body that sets standards for motor starters, enclosures, and other electrical equipment.

Question 3

In a motor control circuit, a normally open (NO) contact is one that:

Accepted Answer

Allows current to flow only when the device is energized or actuated

Answer

A normally open contact has an open circuit in its de-energized (normal) state and only closes to allow current when the coil is energized or the device is actuated.

Question 4

What is the function of a thermal overload relay in a motor starter?

Accepted Answer

To disconnect the motor if it draws excessive current for an extended period

Answer

A thermal overload relay protects the motor from damage by opening the control circuit if the motor draws more current than its rated ampacity for too long.

Question 5

In a 3-wire control circuit, the purpose of the holding (seal-in) contact is to:

Accepted Answer

Maintain the motor starter coil energized after the start button is released

Answer

The holding contact (a NO auxiliary contact wired in parallel with the start button) seals in the circuit so the motor continues to run after the momentary start button is released.

EIAT and NEIEP Test Practice Test

EIAT and NEIEP Test Practice Test

EIAT and NEIEP Test Motor Controls