RESIDENTIAL ELECTRICIAN FINAL EXAM REVIEWS

RESIDENTIAL ELECTRICIAN FINAL EXAM REVIEWS Ferrous metal enclosures for grounding electrode conductors shall be _____. a) electrically continuous b) electrically isolated c) not permitted d) rigid metal conduit (RMC) only - CORRECT ANSWER-A: electrically continuous Ref: 250.64(E) Unless listed for the control of other loads, general use dimmer switches shall only be used to control _____. a) switched receptacles for cord-connected incandescent luminaires b) permanently installed incandescent luminaires c) ceiling fans with luminaires d) holiday decorative lighting - CORRECT ANSWER-B: permanently installed incandescent luminaires Ref: 404.14(E) All 125-volt, single-phase, 15- and 20-ampere receptacles installed in residential garages shall be _____. I) protected by a listed arc-fault interrupter II) provided with ground-fault circuit-interrupter protection a) I only b) II only c) both I and II d) neither I nor II - CORRECT ANSWER-B: II only Ref: 210.8(A)(2); 210.12(B) The MAXIMUM allowable ampacity of size 18 AWG fixture wire is _____ amperes. a) 12 b) 10 c) 8 d) 6 - CORRECT ANSWER-D: 6 Ref: Tbl. 402.5 A receptacle outlet installed for a gas or electric clothes dryer in the laundry room of a dwelling unit must be installed within at LEAST _____ feet of the intended location of the dryer. a) 6 b) 4 c) 10 d) 3 - CORRECT ANSWER-A: 6 Ref: 210.50(C) Which of the following listed conductors are required to have overcurrent protection on a residential electric service? a) grounding conductors b) bonding conductors c) identified conductors d) ungrounded conductors - CORRECT ANSWER-D: ungrounded conductors Ref: 290.9 Given: a 40-gallon electric water heater has a nameplate rating of 4,500 watts at 240 volts. What is the MAXIMUM standard size circuit breaker the NEC permits to protect the water heater? a) 20 amperes b) 25 amperes c) 30 amperes d) 45 amperes - CORRECT ANSWER-C: 30 amperes Ref: 422.11(E)(3); 240.6(A); Current Formula Sol: I = P/E I = 4500 va / 240 volts I = 18.75 amps x 150 percent I = 28.1 amperes If a cable or raceway enters an enclosure such as a meter base, above uninsulated live parts in a wet location, the fittings used to connect the enclosure must be _____ for wet locations. a) identified b) marked c) suitable d) listed - CORRECT ANSWER-D: listed Ref: 312.2(A) In general, the power supply cord to a mobile home shall have a MAXIMUM rating of _____. a) 50 amperes b) 60 amperes c) 100 amperes d) 125 amperes - CORRECT ANSWER-A: 50 amperes Ref: 550.10(A) A 150 kVA, single-phase transformer having a secondary voltage of 120/240 is to be installed at a multi-family dwelling. The current available at the secondary is _____ amperes. a) 329 b) 421 c) 625 d) 729 - CORRECT ANSWER-C: 625 Sol: I = P/E I = 150,000 va / 240 volts