CPT Electrical & Mechanical Fundamentals 2

Question 1

A motor nameplate reads 460V, 3-phase. What happens if this motor is connected to 230V, 3-phase?

Accepted Answer

Motor draws excessive current and overheats

Answer

Running a motor at half its rated voltage causes it to draw excessive current to maintain torque, leading to overheating and potential burnout.

Question 2

Which type of bearing is best suited for applications with high radial loads and moderate axial loads?

Accepted Answer

Tapered roller bearing

Answer

Tapered roller bearings are designed to handle both high radial loads and significant axial (thrust) loads simultaneously.

Question 3

What does the term 'power factor' describe in an AC electrical circuit?

Accepted Answer

The ratio of real power to apparent power

Answer

Power factor is the ratio of real (useful) power in watts to apparent power in volt-amperes, indicating how efficiently electrical power is being used.

Question 4

In a V-belt drive system, what is the consequence of excessive belt tension?

Accepted Answer

Premature bearing failure and belt wear

Answer

Excessive belt tension places extreme radial loads on shaft bearings, accelerating bearing wear while also shortening belt life.

Question 5

A single-phase 120V circuit has a resistance of 12 ohms. What is the current flow?

Accepted Answer

10 A

Answer

Using Ohm's Law: I = V/R = 120/12 = 10 amperes.

(CPT) Certified Production Technician Practice Test

(CPT) Certified Production Technician Practice Test

CPT Electrical & Mechanical Fundamentals 2