Conductors and Cables Module Nine
Which of the following represents the largest wire size? a. 50 b. 10 c. 4 d. 4/0
4/0
The NEC specifies a minimum of ___________ for connections made to wiring devices or for splices. a. 4" b. 6" c. 8" d. 10"
6"
A conductor's operating temperature is not determined by ___________. a. ambient temperature b. current flow c. current flow in bundled conductors d. the number of conductor strands
the number of conductor strands.
Polyethylene is used primarily for insulation of _________________. a. high-voltage conductors b. control and communications wiring c. THHN wiring d. XHHW wiring
control and communications wiring
The designation for one thousand circular mils is _________________.
square inches
In some cases, fixture wires may be used as a substitute for branch circuit conductors. a. True b. False
False
The maximum size solid wire that should be terminated in pull boxes and disconnects is ________. a. No. 6 b. No. 8 c. No. 10 d. No. 12
No. 8
All of the following help to determine how good a material will be for the construction of wire except ___________________. a. availability b. cost c. conductivity d. molecular weight
molecular weight
A(n) ___________________ is a piston-like plug that is attached to a string or rope for pulling through conduit using a power fishing system.
mouse
Composed of foam rubber, a(n) ________ fits inside a piece of conduit and is propelled by compressed air or vacuumed through the conduit run, pulling a line or tape.
mouse
To prevent unwanted ground loops, instrumentation cable shielding is, ___________. a. not grounded at both ends of the wire b. grounded at both ends of the wire c. floated on both ends d. always ungrounded
not grounded at both ends of the wire.
A pulling line is usually made of ___________. a. stranded wire b. wire rope c. steel tape d. nylon or other synthetic material
nylon or other synthetic material
Some jackets have a(n) _________________________ that allows the jacket to be peeled back without the use of a knife or cable cutter.
nylon rip cord
Type USE cable can be used for __________. a. aboveground installation only b. underground installation within a special PVC pipeline c. underground installation including direct burial d. indoor applications only
underground installation including direct burial.
What are the colors of insulation on the conductors for a three-conductor NM cable? a. One white or gray, one red, and one black b. Two white or gray and one red c. One white or gray, one red, one black, and a grounding conductor d. One green, one white or gray, one blue, and a grounding conductor
One white or gray, one red, one black, and a grounding conductor
What does the letter R stand for with regard to insulation coding?
Rubber
A conductor's size refers to the cross-sectional area of both the current-carrying wire and the insulation. a. True b. False
True
During a pull, cable may be attached to the pulling rope using a(n) _______________.
wire grip
Compact stranding is used ______________. a. when installing larger conduit sizes b. when decreasing the ampacity of an existing service c. with aluminum conductors d. in corrosive environments
with aluminum conductors
Type MV cable is suitable for _____________________________. a. use in wet locations b. use in dry locations c. direct burial d. all of the above
all of the above
A conductor's ____________________ is the current the conductor can carry continuously without exceeding its temperature rating.
ampacity
On a cable puller, the _____________ is the part on which the pulling rope is wrapped and pulled.
capstan
Type NMC cable is suitable for all of the following except __________. a. dry locations b. damp locations c. corrosive locations d. embedding in concrete
embedding in concrete
A(n) __________ is a manually operated device that is used to pull a wire through conduit.
fish tape
Polyethylene (PE) is used primarily for ___________. a. the manufacture of TW and THW insulation b. insulation of control and communication wiring c. high-voltage cables d. high-temperature insulation
insulation of control and communication wiring.
True or False? All current-carrying conductors (including the grounded conductor) must be insulated when used on the inside of buildings.
True
True or False? NEC Table 310.15(B)(16) covers conductors rated up to 2,000V where not more than three conductors are installed in a raceway or cable.
True
True or False? Type NMC is suitable for direct burial.
True
What letter must be included in the marking of a conductor if it is to be used in a wet, outdoor application? a. D b. O c. I d. W
W
When conductors are installed where the ambient temperature is above _______________ the conductor ampacity must be reduced proportionally with the increase in temperature. a. 25 degrees Celsius b. 30 degrees Celsius c. 45 degrees Celsius d. 60 degrees Celsius
30 degrees Celsius
The difference between AC cable and MC cable is _____________. a. AC cable has a maximum of four conductors; MC has a maximum of six b. AC cable has a bonding strip; the MC ground is its metal cladding c. AC cable has fire-retardant wraps on individual conductors; MC cable does not d. AC cable is sized from 10 AWG to 4/0; MC is sized from 18 AWG to 2,000 kcmil
AC cable has fire-retardant wraps on individual conductors; MC cable does not
____________________ is the maximum current in amperes a conductor can carry continuously under the conditions of use without exceeding its temperature rating.
Ampacity
True or False? Polyethylene is the base material used for the manufacture of TW and THW insulation.
False
When feeding conductors into long runs of conduit, it is important to apply lubricant to the conductors only, and not to the conduit. a. True b. False
False
A type of thermoset insulation is ________. a. RHW b. THW c. THHW d. PVC
RHW
What service conductor may be bare, green, or green with a yellow stripe? a. The grounding conductor of a multi-conductor cable b. The neutral conductor of a multi-conductor cable c. The ungrounded conductor of a multi-conductor cable d. The high leg of a four-wire, delta-connected secondary
The grounding conductor of a multi-conductor cable.
A(n) __________________ is a circle which has a diameter of 1 mil.
circular mil
Type UF cable ____________________. a. is commonly called Romex b. is suitable for direct burial c. is commonly referred to as BX d. consists of five conductors
is suitable for direct burial.
The ampacity ratings of conductors can be found in _________. a. NEC Chapter 1 b. NEC Articles 348 through 352 c. NEC 310.15(B)(16) through 310.15(B)(21) d. NEC Chapter 9
NEC 310.15(B)(16) through 310.15(B)(21)
To determine the ampacity of copper conductors where conductors are used as a single conductor in free air at ambient temperatures of 30 degrees celsius, use__________. a. NEC Table 310.15(B)(16) b. NEC Table 310.15(B)(17) c. NEC Table 310.15(B)(18) d. NEC Table 310.15(B)(19)
NEC Table 310.15(B)(17)