NEC EXAM 3 QUESTIONS AND ANSWERS
All single-phase, 15-or 20-ampere branch-circuits supplying outlets or devices installed
in residential kitchens or similar rooms shall be protected by a listed arc-fault interrupter
of the same___________ type. - Answers -Combination
Article 210.12(A), 70-64
Unless listed for the controls of other loads, general-use dimmer switches shall only be
used to control __________ - Answers -Permanently installed incandescent luminaires
Article 210.50(C), 70-68
Which of the following listed conductors are required to have over-current protection on
a residential electric service? - Answers -Ungrounded conductors
Article 230.90, 70-95
Where a 40-gallon storage-type electric water heater has a nameplate rating of 4,500
watts @ 240 volts, what is the MAXIMUM standard size circuit breaker the NEC permits
to protect the water heater? - Answers -28.1 amperes = 30 amperes
I = P/E = 4,500 VA/240 V = 18.75 amperes x 150% = 28.1 amperes
Article 422.11(E)(3), 70-287, Table 240.6(A), 70-100
Receptacle outlets installed in or on floors of dwelling units shall not be counted as part
of the required number of receptacle outlets, if they are MORE than__________ from
the wall. - Answers -18 inches
Article 210.52(A)(3), 70-68
Disregarding exceptions, the power supply cord to a mobile home shall have a
MAXIMUM rating of ___________ - Answers -50 amperes
Article 550.10(A), 70-473
A 150 kVA, single-phase transformer having a secondary voltage of 120/240 is to be
installed at a multifamily dwelling. The current available at the transformer secondary
is___________ - Answers -625 amperes
I = 150,000VA/240 V = 625 amperes
When the heating, air-conditioning, or refrigeration equipment is installed on the roof of
an apartment complex, a 125-volt, 15- or 20-ampere rated receptacle
All single-phase, 15-or 20-ampere branch-circuits supplying outlets or devices installed
in residential kitchens or similar rooms shall be protected by a listed arc-fault interrupter
of the same___________ type. - Answers -Combination
Article 210.12(A), 70-64
Unless listed for the controls of other loads, general-use dimmer switches shall only be
used to control __________ - Answers -Permanently installed incandescent luminaires
Article 210.50(C), 70-68
Which of the following listed conductors are required to have over-current protection on
a residential electric service? - Answers -Ungrounded conductors
Article 230.90, 70-95
Where a 40-gallon storage-type electric water heater has a nameplate rating of 4,500
watts @ 240 volts, what is the MAXIMUM standard size circuit breaker the NEC permits
to protect the water heater? - Answers -28.1 amperes = 30 amperes
I = P/E = 4,500 VA/240 V = 18.75 amperes x 150% = 28.1 amperes
Article 422.11(E)(3), 70-287, Table 240.6(A), 70-100
Receptacle outlets installed in or on floors of dwelling units shall not be counted as part
of the required number of receptacle outlets, if they are MORE than__________ from
the wall. - Answers -18 inches
Article 210.52(A)(3), 70-68
Disregarding exceptions, the power supply cord to a mobile home shall have a
MAXIMUM rating of ___________ - Answers -50 amperes
Article 550.10(A), 70-473
A 150 kVA, single-phase transformer having a secondary voltage of 120/240 is to be
installed at a multifamily dwelling. The current available at the transformer secondary
is___________ - Answers -625 amperes
I = 150,000VA/240 V = 625 amperes
When the heating, air-conditioning, or refrigeration equipment is installed on the roof of
an apartment complex, a 125-volt, 15- or 20-ampere rated receptacle
