#1
Which organization develops the National Electrical Code (NEC)?
National Fire Protection Association (NFPA)
ExplanationNFPA develops the NEC to establish electrical safety standards.
#2
What is the primary purpose of the NEC?
To ensure electrical safety for people and property
ExplanationNEC's primary purpose is ensuring safety through electrical standards.
#3
What does the term 'ground fault' refer to in electrical systems?
An unintentional connection between an electrical conductor and the ground
ExplanationA ground fault is an unintentional connection to ground.
#4
Which of the following is an essential component of an electrical grounding system?
Grounding electrode
ExplanationA grounding electrode is a vital part of electrical grounding.
#5
What is the minimum clearance requirement above a roof for electrical service conductors?
18 inches
ExplanationNEC requires a minimum 18-inch clearance above roofs for service conductors.
#6
Which NEC article covers requirements for electrical installations in hazardous locations?
Article 500
ExplanationArticle 500 in NEC specifies requirements for hazardous location installations.
#7
What is the maximum number of conductors allowed in a conduit, as per NEC guidelines?
6
ExplanationNEC permits a maximum of 6 conductors in a conduit.
#8
Which of the following is NOT covered by the NEC?
Telecommunication systems
ExplanationNEC does not cover standards for telecommunication systems.
#9
What is the purpose of Article 100 in the NEC?
Defines important terms used throughout the code
ExplanationArticle 100 in NEC defines crucial terms for code interpretation.
#10
What is the typical voltage threshold for defining 'low voltage' in electrical systems?
Below 50 volts
ExplanationLow voltage in electrical systems is typically below 50 volts.
#11
In the NEC, what is the function of Article 250?
Rules for grounding and bonding
ExplanationArticle 250 in NEC provides rules for grounding and bonding.
#12
What is the purpose of an arc fault circuit interrupter (AFCI)?
To detect and mitigate the risk of electrical arcs
ExplanationAFCI's purpose is detecting and mitigating the risk of electrical arcs.
#13
What is the minimum height requirement for switches and receptacles above the floor according to the NEC?
18 inches
ExplanationNEC mandates a minimum height of 18 inches for switches and receptacles above the floor.
#14
What is the purpose of bonding jumpers in electrical installations?
To connect metal parts to ensure electrical continuity
ExplanationBonding jumpers connect metal parts for electrical continuity in installations.
#15
Which NEC section covers overcurrent protection?
Article 240
ExplanationArticle 240 of NEC addresses overcurrent protection requirements.
#16
What is the primary purpose of a GFCI (Ground Fault Circuit Interrupter)?
To detect ground faults and shut off power
ExplanationGFCI's main purpose is detecting ground faults and cutting off power.
#17
What is the function of a surge protective device (SPD) in an electrical system?
To protect against transient voltage spikes
ExplanationSPD's function is protecting against transient voltage spikes in electrical systems.
#18
What is the primary function of a tamper-resistant receptacle?
To prevent electrical shock from insertion of foreign objects
ExplanationTamper-resistant receptacles prevent electrical shock from foreign object insertion.
#19
What is the purpose of a line reactor in an electrical system?
To mitigate harmonics and improve power quality
ExplanationA line reactor's purpose is mitigating harmonics and enhancing power quality.