Deck 27: Service-Entrance Equipment

Question 1

What are service lateral conductors?

Answer 1

If installed by the electric utility, the conductors installed between the pad-mounted transformer and the meter are called service lateral conductors.

Question 2

Using an electric rate of $0.07824 per kWh, calculate the cost of running ten 100W lamps for six hours.

Answer 2

Cost = watts × hours used × cost per kWh/1000
10 lamps at 100W = 1,000W
46.9¢

Question 3

A panelboard must not be installed in a(n) ____________________.

Answer 3

bathroom

Question 4

If extra support is not to be provided, the mast service conduit must be at least ____ in. in diameter.

A) 1
B) 1-1/2
C) 2
D) 2-1/2

Question 5

When using a metal water pipe as a grounding electrode, a(n) ____________________ is required.

Question 6

A main service disconnect shall not be installed in a ____.

A) bedroom
B) laundry room
C) garage
D) bathroom

Question 7

Under no circumstances shall the service entrance conductors be less than ____ ft. above finished grade.

A) 6
B) 8
C) 10
D) 12

Question 8

A working space not less than ____ in. wide and 3 ft deep must be provided in front of electrical equipment, such as panelboards A and B in this residence.

A) 16
B) 24
C) 30
D) 36

Question 9

NEC 300.4(F) states that if ____ AWG or larger ungrounded circuit conductors enter a cabinet, box enclosure or raceway, an insulating bushing or equivalent must be used.

A) 4
B) 6
C) 8
D) 10

Question 10

____________________ conductors are permitted to be attached to and supported by the service mast.

Question 11

For a one-family residence, the minimum size main service disconnecting means is ____ three-wire.

A) 30-ampere
B) 60-ampere
C) 100-ampere
D) 150-ampere

Question 12

A 4 AWG bare copper conductor at least 20 ft (6.0 m) long installed identically to the steel reinforcing rod is also permitted as a concrete-encased grounding electrode. This is often referred to as a(n) ____________________ ground.

Question 13

For typical residential wiring, the grounding electrode conductor is run between the ____________________ neutral/ground terminal bar and the grounding electrode system.

Question 14

An exterior raceway containing service entrance conductors must be ____________________ and arranged to drain.

Question 15

Bonding at service-entrance equipment is very important because service-entrance conductors do not have ____________________ at their line side, other than the electric utility company's primary transformer fuses.

Question 16

It is extremely important that a disconnect or panelboard used as service equipment be marked "____________________."

Question 17

NEC ____________________ provides rules for working space around electrical equipment.

Question 18

Ground clamps used for bonding and grounding must be ____.

A) approved
B) copper
C) steel
D) listed for the purpose

Question 19

Ground rods must be at least ____ ft. in length

A) 6
B) 8
C) 10
D) 12

Question 20

What is a service drop?