Wiring Methods
Metal conduit installed in indoor wet locations must have. MINIMUM airspace clearance of ........,between the conduit and the wall or supporting surface.
1/4 300.6(D)
Where direct-burial conductors emerge from below grade and extend up a pole, the conductors must be protected by raceways up to a height of 8 feet above finished grade and in no case shall the protection be required to exceed........below finished grade.
18 inches 300.5(D)(1)
When electrical wiring passes through fire-resident-rated walls,partitions,floors, or ceilings, openings around the electrical penetrations shall be
Firestopped 300.21
The reason the NEC requires all phase conductors of an AC electrical system to be in the same ferrous metal raceway is to reduce.......
Inductive heat 300.20(A)
A........ shall be used at the end of a conduit that terminates underground where the conductors emerges as a direct burial wiring method.
Bushings 300.5(H)
In general,when conductors of different insulation rating are installed in a common raceway and the voltage is 600 volts or less, the NEC mandates:
The maximum operating voltage not to exceed the insulation rating of the lowest insulation rating of any conductor in the raceway. 300.3(C)(1)
An underground run of conduit or direct buried cables in or under an airport runway, tarmac or concourse shall be buried a Minimum depth of
1 1/2 feet Tbl. 300.5, Col. 1-5
Where an electrical metallic tubing (EMT) is installed in exposed or concealed locations under metal- corrugated sheet metal roofing decking,a distance of at LEAST......, must be maintained from the nearest surface of the roof decking to the EMT.
1 1/2 inch 3004(E)
In general. When installing Type NM cable through bored holes in wooden studs, the holes shall be bored so that the edge of the holes is NOT less than ........ From the outside edge of the wooden stud.
1 1/4 inches 300.4(A)(1)
In general, cables or raceways shall be permitted to be laid in notches in wood studs where the cable or raceway at those points is protected against nails or screws by a steel plate at LEAST........, thick.
1/16 inches Tbl. 300.4(A)(2)
Given: type UF cable is to be used for direct burial residential branch-circuits of 120 volts. The conductors are GFCI protected and over current protection is rated 20 amperes; the cables so not cross under any driveways or concrete. What is the minimum permitted burial depth of the cable
12 inches
What is the Minimum burial depth of intermediate metal conduit (IMC) containing conductors of 600 volts or less,under a residential gravel driveway, where GFCI protection is not provided
12 inches
Underground service conductors that are not encased in concrete and that are buried 18 inches or more below grade shall have their location identified by a warning ribbon placed at LEAST......,above the underground installation
12 inches 300.5(D)(3)
In general, direct-burial cables of 13,000 volts must be buried at a depth of NOT less than ........
30 inches Tbl. 300.50
Where raceways contain conductors of less than 600 volts and where insulated conductors of size........or larger enter a box or cabinet, the conductors must be provided with an insulating bushing. (No Exceptions)
6 AWG 300.4(G)
At LEAST.......of free conductor,measured from the point in the box where it emerges from its raceway or cable sheath,shall be left at each outlet box,switch box,and junction box for splices or to connect to fixtures and devices
6 inches 300.14
Where a vertical raceway contains three (3) size 3/0 AWG copper conductors, the conductors shall be supported at the top and at intervals NOT greater than ........
80 feet Tbl. 300.19(A)
In general, conductors in raceways must be ........ between outlet boxes and there shall be no splice or tap within a raceway itself
Continuous 300.13(A)
A metal box or terminal fitting having separately bushed holes for each conductor,shall be used whenever is made from conduit to
Knob and tube wiring
All metallic switchgear rated for 600 volts shall be provided with a grounding busbar for the purpose of connecting the.....
Metallic shield of cables 300.40
Which of the following circuits are prohibited for the grounded conductor to be dependent upon receptacle devices for continuity?
Multiwire branch-circuits 300.13(B)
Wiring in ducts of commercial cooking equipment shall be
Prohibited 300.22(A)
Underground direct-burial service entrance conductors shall be.......
Protected from damage due to ground movement using "S" loops 300.5(J) & FPN
Where conduit is installed on the exterior wall of a building,the interior of these raceways shall be considered to be a ........,
Wet location 300.9
Where conductors carrying alternating current are installed in ferrous metal raceways,...,,,
all phases conductors, the grounded conductor and equipment grounding conductors shall be grouped together 300.20(A)