Cable, Raceway, and Enclosure Requirements Flashcards
All building wiring must be enclosed in a cable, conduit, wireway, or raceway.
TRUE
-conductors are snaked through conduit or tubing, are laid in a
wireway, or are contained in cables, and
-secured to structural framing.
During installation
must be exercised in placing conductors, as conductors and
insulation can be easily damaged.
Care
_______ that are run through a raceway must have sufficient
_________ to prevent overheating.
Conductors, open -air space
The number of current-carrying conductors
that can run through a raceway is _________ by
______.
limited, code
A __________ found in a
raceway Is any ungrounded conductor or
grounded conductor.
current-carrying conductor
___________ (bare or green
colored) and _______ are not current carrying and are not counted.
Equipment grounding, shared neutral conductors
Rigid conduit and tubing
- rigid metal and nonmetallic conduit
- IMC
- EMT
- ENT
are favorite raceway materials used to protect conductors in all
types of buildings.
Rigid conduit and tubing
it is available in ________, therefore, must be _______ to
accommodate changes in direction.
Ridgid conduit and tubing, straight lengths, bent
bends must be made no smaller than the minimum radius
specified by code, about _________ the conduit diameter.
6 to 8 times
conduit and tubing can have up to _________ or the
equivalent ________ in one run.
four 90° bends, 360° total
In runs requiring more bends, a __________ is added in the run
assist in pulling conductors and to allow access.
Pull box
- flexible metal conduit
- liquid tight flexible metal
- nonmetallic conduit
Flexible conduit
offers the advantage of easier installation and can be
salvaged easily when circuits are rearranged.
Flexible conduit
It is used where mechanical protection is needed and
easy relocation of equipment is desired.
It can have up to four 90° bends or the equivalent (360°
total) in one run.
Flexible conduit
_________ should be supported to prevent _______ against structure and to
avoid _______ its end fittings.
Conduit, wearing away, stressing
______ and ______ must be supported within _____
of a box or other connection and at intervals of ______
(about 3 m).
Rigid conduit, tubing, 3 ft, 10 ft
can be used as the
grounding conductor.
Continuous, metal conduit
must be supported every _______ (1.35
m) and within _____ (300 mm) of a box, except up to _______ (about 1 m) is allowed at usage points where
flexibility is required (e.g., a pump motor or air
conditioner condensing unit) and 6 ft (about 2 m) sy Ps
between a recessed light fixture and a box.
Flexible conduit, 4 to 6 in, 12 in, 36
in,
___ and ___ can be used as grounding
conductor if it is continuous and_ properly
bonded.
IMC, EMT
It is required for flexible conduit.
lt can be bare or insulated.
Grounding conductor
Cannot be use as the grounding conductor.
Rigid nonmetallic conduit and tubing (ENT)
Manufactured from __________ that have
very high rates of ___________ (over 6 in
for a 100°F temperature change per 100 ft/over
300 mm in a 50°C temperature change per 30
mM).
Rigid nonmetallic conduit and tubing (ENT), thermoplastics, thermal expansion
Permitted in single- and multifamily dwelling units and some other buildings.
Nonmetallic-sheathed cable (NM and NMC)
____ and _____ must be supported every 4-6(1.35 m) and within 12 in (300
Mm) of a box.
NM, NMC
ls for use in dry, indoor applications.
Armored cable (AC)
Bends are limited to no less than five times the diameter.
Armored cable (AC)
________ and _______ should be installed away from locations where
building occupants might use it as a handhold or footstep.
Conduit, cable
_________ should be provided at the lowest point in a conduit run.
Drain holes
________ and ________ should be carefully removed to prevent
damage to conductor insulation.
Drilling, culling burrs
cannot be embedded in masonry, concrete, or plaster.
Armored cable (AC)
All ____________ must be made in a _______ such as
panelboard, junction, or device box, fixture, or appliance.
electrical connections, protective enclosure
All electrical connections must be made in a protective enclosure such as
___________________________________
panelboard, junction, or device box, fixture, or appliance.
Every switch, outlet, and connection must be contained in an __________
and every lighting fixture must be mounted in a _______.
electrical box, box
Every ______________ must be contained in an electrical box
and every _________ must be mounted in a box.
switch, outlet, and connection, lighting fixture
All wirings must begin or terminate at a ________ or in a box that is
housing switch, luminaire connection, receptacle, conductor junction, or
some similar terminal fitting.
panelboard
______________ must be mounted so that the blank cover plate is visible and
readily accessible.
Junction boxes
There are requirements that specify that a
certain type of electrical box be installed for a
specific purpose.
FALSE
Normally installed overhead for lightning
installation.
Octagon and round boxes for lighting outlets
The ______ and ________ of conductors to be installed in a box influences
selection of type of box and box size.
size, number
the more conductors and/or the conductor size, the bigger the box must
be.
TRUE
The capacity of a box, in cubic inches, is determined by its ____________
length, width,
and depth.
conductor that runs through the box is counted as two
conductor and each conductor that terminates in the box counts as one.
FALSE
________ and _____ that do not leave
the box, such as an _________ wire, are
not counted.
Fixture wires, conductors, internal grounding
One conductor is deducted for one or more
grounding conductors that enter the box.
TRUE
Conductors in an electrical box must have
sufficient open air space to prevent
overheating.
TRUE
