Conductors with _____ marked on the insulation are NOT approved for use in a
wet location. ~CORRECT ANSWER~✓✓THHN
conductors with THHN insulation are approved for use in dry and damp
locations only and conductors with THWN, THHW, and THW insulation are
recognized for use in dry and wet locations.
Given: A one-family dwelling unit with a demand load of 200 amperes is
supplied with a 120/240 volt, single-phase, electrical system from the local utility
company. What is the MINIMUM size aluminum THW conductors required for
use as service-entrance conductors for this residence? ~CORRECT
ANSWER~✓✓4/0 AWG
one-family dwelling 120/240 volt, single-phase, service-entrance conductors to
be sized at an ampacity of not less than 83% of the service rating. Therefore, 200
amperes x 83% = 166 amperes; size 4/0 AWG THW aluminum conductors with
an allowable ampacity of 180 amperes should be selected for this dwelling.
Where a 150 kVA, single-phase transformer having a secondary voltage of
120/240 is installed at a multi-family dwelling, the full-load current rating, in
amperes, of the secondary is _____. ~CORRECT ANSWER~✓✓625 amperes
,To find the full-load current rating of the single-phase transformer apply the
single-phase current formula as shown:I = (150 kVA x 1000) / 240 volts =
15,000/240 = 625 amperes
Which one of the following listed circuit breakers is NOT a standard ampere
rating? ~CORRECT ANSWER~✓✓75 amperes
the standard ampere ratings for fuses and circuit breakers. A circuit breaker with
an ampere rating of 75 amperes is not a standard ampere rating.
The MINIMUM length of free conductor to be left at each junction box for the
purpose of splicing conductors, or making connections to illuminares or devices
shall be _____ . ~CORRECT ANSWER~✓✓6 inches
free conductor is to be left at each junction box for splices or the connection of
luminaires or devices. The intent of this rule is to ensure enough conductor slack
for the terminal connections or splices to be made easily.
In general, overhead service-drop conductors shall NOT be smaller than _____.
~CORRECT ANSWER~✓✓8 AWG copper
overhead service-drop conductors to be not smaller than 8 AWG copper or 6
AWG aluminum or copper-clad aluminum. Do not get service-drop conductors,
the overhead conductors between the utility electric supply system and the
service point, confused with the service-entrance conductors, the conductors
from the service point from the utility company to the service disconnecting
means.
, When a galvanized eye-bolt is to be used as the point of attachment for an
electrical service, the NEC requires the eye-bolt to be installed NOT less than
_____ above finished grade. ~CORRECT ANSWER~✓✓10 ft.
provide adequate vertical clearance of the conductors and prevent physical
damage to the conductors and prevent persons from making accidental contact
with the conductors which may create a shock hazard or electrocution. In no case
shall the point of attachment of the service-drop conductors to be less than 10 ft.
above finished grade.
Why is electrical continuity required for metallic conduit? ~CORRECT
ANSWER~✓✓To establish an effective ground-fault path and facilitate the
operation of the over-current protective device.
Electrical continuity is required for metallic conduit to establish an effective
ground-fault path and facilitate the operation of the overcurrent protective
device.
In dwelling units, receptacle outlets installed for countertop surfaces, must be
located above, but NOT more than _____ above the countertop or work surface.
~CORRECT ANSWER~✓✓20 inches
receptacle outlets installed for countertop or work surfaces in dwelling units may
be located on or above, but not more than 20 in. above the countertop or work
surface. The intent of this rule is to eliminate the use of unsightly extension cords
(which reduces the amount of usable countertop space) on the countertop or
work surface to supply cord-and-plug connected appliances. Also, receptacles
wet location. ~CORRECT ANSWER~✓✓THHN
conductors with THHN insulation are approved for use in dry and damp
locations only and conductors with THWN, THHW, and THW insulation are
recognized for use in dry and wet locations.
Given: A one-family dwelling unit with a demand load of 200 amperes is
supplied with a 120/240 volt, single-phase, electrical system from the local utility
company. What is the MINIMUM size aluminum THW conductors required for
use as service-entrance conductors for this residence? ~CORRECT
ANSWER~✓✓4/0 AWG
one-family dwelling 120/240 volt, single-phase, service-entrance conductors to
be sized at an ampacity of not less than 83% of the service rating. Therefore, 200
amperes x 83% = 166 amperes; size 4/0 AWG THW aluminum conductors with
an allowable ampacity of 180 amperes should be selected for this dwelling.
Where a 150 kVA, single-phase transformer having a secondary voltage of
120/240 is installed at a multi-family dwelling, the full-load current rating, in
amperes, of the secondary is _____. ~CORRECT ANSWER~✓✓625 amperes
,To find the full-load current rating of the single-phase transformer apply the
single-phase current formula as shown:I = (150 kVA x 1000) / 240 volts =
15,000/240 = 625 amperes
Which one of the following listed circuit breakers is NOT a standard ampere
rating? ~CORRECT ANSWER~✓✓75 amperes
the standard ampere ratings for fuses and circuit breakers. A circuit breaker with
an ampere rating of 75 amperes is not a standard ampere rating.
The MINIMUM length of free conductor to be left at each junction box for the
purpose of splicing conductors, or making connections to illuminares or devices
shall be _____ . ~CORRECT ANSWER~✓✓6 inches
free conductor is to be left at each junction box for splices or the connection of
luminaires or devices. The intent of this rule is to ensure enough conductor slack
for the terminal connections or splices to be made easily.
In general, overhead service-drop conductors shall NOT be smaller than _____.
~CORRECT ANSWER~✓✓8 AWG copper
overhead service-drop conductors to be not smaller than 8 AWG copper or 6
AWG aluminum or copper-clad aluminum. Do not get service-drop conductors,
the overhead conductors between the utility electric supply system and the
service point, confused with the service-entrance conductors, the conductors
from the service point from the utility company to the service disconnecting
means.
, When a galvanized eye-bolt is to be used as the point of attachment for an
electrical service, the NEC requires the eye-bolt to be installed NOT less than
_____ above finished grade. ~CORRECT ANSWER~✓✓10 ft.
provide adequate vertical clearance of the conductors and prevent physical
damage to the conductors and prevent persons from making accidental contact
with the conductors which may create a shock hazard or electrocution. In no case
shall the point of attachment of the service-drop conductors to be less than 10 ft.
above finished grade.
Why is electrical continuity required for metallic conduit? ~CORRECT
ANSWER~✓✓To establish an effective ground-fault path and facilitate the
operation of the over-current protective device.
Electrical continuity is required for metallic conduit to establish an effective
ground-fault path and facilitate the operation of the overcurrent protective
device.
In dwelling units, receptacle outlets installed for countertop surfaces, must be
located above, but NOT more than _____ above the countertop or work surface.
~CORRECT ANSWER~✓✓20 inches
receptacle outlets installed for countertop or work surfaces in dwelling units may
be located on or above, but not more than 20 in. above the countertop or work
surface. The intent of this rule is to eliminate the use of unsightly extension cords
(which reduces the amount of usable countertop space) on the countertop or
work surface to supply cord-and-plug connected appliances. Also, receptacles
