Free ETO Electrical Systems Operation & Maintenance Questions and Answers

Question 1

What is the primary function of a circuit breaker in electrical systems?

Accepted Answer

To protect circuits from overload

Answer

A circuit breaker's primary function is to protect electrical circuits from damage caused by overcurrent or short circuits. When an overload or fault occurs, the circuit breaker automatically trips, interrupting the flow of electricity. This prevents overheating of wires, potential fires, and damage to electrical appliances.

Question 2

Which component is used to step down voltage in electrical distribution systems?

Accepted Answer

Transformer

Answer

A transformer is an electrical device that uses electromagnetic induction to change AC voltage levels, either stepping it up or stepping it down. In electrical distribution systems, step-down transformers are commonly used to reduce high transmission voltages to lower, safer voltages suitable for residential and commercial use.

Question 3

What is the typical purpose of a grounding system in electrical equipment?

Accepted Answer

To prevent electrical shock

Answer

The typical purpose of a grounding system in electrical equipment is to provide a safe path for fault currents to flow directly to the earth. In the event of an electrical fault, grounding prevents dangerous voltage buildup on equipment enclosures, thereby protecting personnel from severe electrical shock. It acts as a critical safety measure.

Question 4

Which device is used to measure electrical current?

Accepted Answer

Ammeter

Answer

An ammeter is a specific electrical measuring instrument designed to measure the flow of electrical current in amperes. It is connected in series within a circuit to accurately determine the magnitude of the current passing through that part of the circuit. Other devices like voltmeters measure voltage, and ohmmeters measure resistance.

Question 5

What is the primary role of an electrical relay?

Accepted Answer

To switch circuits using a low power signal

Answer

An electrical relay is an electromechanical switch that uses a low-power electrical signal to control a higher-power circuit. It works by using an electromagnet to open or close contacts, allowing a small current to switch a much larger current or voltage. This enables remote control and protection in various electrical systems.

ETO - Electro-Technical Officer Practice Test

ETO - Electro-Technical Officer Practice Test

Free ETO Electrical Systems Operation & Maintenance Questions and Answers