CEA CEA Motor Controls and Control Circuits Questions and Answers

Question 1

What is the primary purpose of a magnetic motor starter?

Accepted Answer

To provide remote switching and overload protection for a motor

Answer

To convert AC to DC power

Answer

To increase motor speed above nameplate rating

Answer

To reduce the motor's power factor

Question 2

In a three-phase motor control circuit, what is the function of the overload relay heater element?

Accepted Answer

It senses excess current and trips the control circuit to stop the motor

Answer

It heats the motor windings to prevent condensation

Answer

It boosts voltage during startup

Answer

It balances the three-phase load

Question 3

Which type of motor starter reduces inrush current during startup by applying reduced voltage?

Accepted Answer

Reduced-voltage starter

Answer

Full-voltage (across-the-line) starter

Answer

Reversing starter

Answer

Multi-speed starter

Question 4

In a control circuit, what does a normally open (NO) contact do when the coil is energized?

Accepted Answer

It closes to complete the circuit

Answer

It remains open

Answer

It opens the power circuit

Answer

It reverses motor rotation

Question 5

What is a 'seal-in' or 'holding' contact in a motor control circuit?

Accepted Answer

An auxiliary contact wired in parallel with the start button to maintain the circuit after the button is released

Answer

A contact that locks out the panel door

Answer

A contact that seals moisture out of the enclosure

Answer

A contact used only in reversing starters

Question 6

According to NEMA standards, what does a NEMA 12 enclosure protect against?

Accepted Answer

Dust, dirt, and dripping non-corrosive liquids for indoor use

Answer

Submersion in water

Answer

Explosive gases and dust

Answer

Outdoor rain and sleet