1) Low voltage (high voltage drop) in a home can be caused by ____. a) Low voltage (high voltage drop) in a home can be caused by ____. b) a circuit that is too long c) poor connections at the terminals d) all of the above 2) What's the largest size solid conductor generally permitted to be installed in a raceway? a) 10 AWG b) 8 AWG c) 6 AWG d) None of the above 3) What determines the ampacity of a wire? a) size b) length c) its temperature rating d) none of the above 4) What unit of measurement is used for the diameter of wires? a) inches or millimeters b) A mil (thousandth of an inch) c) US NEC Table 310.15B d) NM, AC or ACT types. 5) What are the colors of the conductors in 3-wire nonmetallic-sheathed cable? a) Black, Red, and White b) Black, Red, and Purple c) White, Green and Yellow d) None of the above 6) What's the difference between Type AC and ACT armored cable? a) AC is 5x times bigger than ACT b) Type ACT cable features thermoplastic insulation c) AC is cooper and ACT is aluminum wire is used d) There is no difference 7) Ampacity means: a) 8 AWG conductors when installed in raceway b) the diameter of conductors that usually give in a unit called a mil. c) the maximum current that a conductor can carry continuously without exceeding its temperature rating. d) none of the above 8) Conductors must be _____ against overcurrent by fuses or circuit breakers rated NOT more than the ampacity of the conductors. a) connected b) protected c) overheated d) carry e) all of the above 9) Aluminum conductors have a ____ resistance compared to a copper conductor of the same size. When considering voltage drop, a conductor's resistance is a key ingredient. a) lower b) higher c) almost the same d) 2x times e) zero 10) What does this picture represent? a) showing line-to-line and line to neutral laods. b) incorrect electrical wiring done by a new technician that eventually has to be fixed c) typical knob-and-tube wiring from the 1930s. 11) What's the voltage rating of conductors in Type NMC cable? a) 600 Volts or less b) 600 Volts or more c) 220 Volts or less d) 24 Volts or less 12) Most electricians still refer to nonmetallic sheathed cable as ____? a) 2 conductors cable b) Romex c) UL 719 cable d) jacket cable 13) The suffix __ means that the conductors have 90 °C insulation a) A b) B c) C d) TW 14) What's the formula for calculating voltage drop? a) V = I * R b) E = MC^2 / V * I * R c) VD = (2 * K * I * L)/CMA d) VD = (K * I * L)/CMA * 2 15) Nonmetallic-sheathed cable is: a) a factory assembly of 8 conductors enclosed in low voltage cable b) a factory assembly of two or more insulated conductors enclosed within an overall nonmetallic jacket. c) 6 AWG cooper conductor covered intermediate metal conduit d) none of the above 16) NM-B, NMC-B and NMS-B are: a) three types of branch circuits b) three types of neutral conductors c) three types of requirements for raceways and cable installation d) three types of nonmetallic-sheathed cable 17) Identify this a) PVC cable b) Armored cable wire c) Fiber optic cable d) Shielded twisted pair Cat.6 18) Service-entrance cable is: a) a cable that installed parallel to framing members or furring strips. b) a single conductor or multiconductor assembly provided with or without an overall covering, primarily used for services. c) a cable that uses for circuits rated 100 amp or more, or marked for conductor size 14 through 1 AWG. d) all of the above

MTA quiz1 class 2

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