Applied Grounding and bonding level 1: lesson 5

? is/are defined as the conductors and equipment for delivering electric energy from the serving utility to the wiring system of the premises served.

Select one:

a. service :)

b. service conductors x

c. service-entrance conductors x

d. service equipment x

Where a system is grounded, the service must be supplied with a(n) ? conductor.

Select one:

a. bonding x

b. equipment grounding x

c. grounded :)

d. neutral x

What is the minimum-size aluminum or copper-clad aluminum main bonding jumper (wire-type) for a service if the largest ungrounded service conductor is 500 kcmil copper?

Select one:

a. 3 AWG

b. 2 AWG

c. 1/0 AWG

d. 3/0 AWG

Feedback

Your answer is correct.

The correct answer is: 3/0 AWG

The grounded conductor of a service must always be a neutral conductor.

Select one:

True

False

Feedback

The correct answer is 'False'.

Where the utility transformer supplying a service is located outside the building, a grounding connection is not required to be made outside a building or structure served by a grounded electrical service.

False

A grounding electrode connection is required to be made at a(n) ? location anywhere from the load end of the overhead service conductors, service drop, underground service conductors, or service lateral up to and including the terminal or bus to which the grounded conductor is connected in the service disconnecting means.

accessible

A meter socket enclosure sealed by the utility makes the enclosure inaccessible, by definition.

false

Which of the following is not one of the four conductors in the grounding and bonding scheme for a service supplied by a grounded system?

Select one:

a. Equipment grounding conductor

b. Grounded conductor

c. Grounding electrode conductor

d. Main bonding jumper

e. System bonding jumper

The correct answer is: System bonding jumper

Where a service is supplied by an ungrounded system, the grounded conductor is required to be routed to the service disconnecting means enclosure and bonded to it.

False

Where a service is supplied by a grounded system, the grounded conductor is required to be routed to the service disconnecting means enclosure and bonded to it.

true

The grounded conductor is required to be routed to the service equipment along with its associated ungrounded service conductors.

true

The main bonding jumper in a service disconnecting means enclosure can be in which of the following forms?

Select one:

a. Bus

b. Green screw

c. Wire

d. Any of the above

The correct answer is: Any of the above

If a service disconnecting means is made up of six disconnects in separate enclosures grouped in the same location, how many main bonding jumpers will be required for the service?

Select one:

a. 1

b. 2

c. 4

d. 6

6

Where the service disconnecting means is made up of two to six disconnects that are compartmentalized in a single listed service equipment assembly, how many main bonding jumpers are required within the listed assembly?

Select one:

a. 1

b. 6

c. As many as the number of service disconnects

d. None; a main bonding jumper is not required in a listed assembly

1

If a main bonding jumper is a wire type, what NEC table is used to size it?

Select one:

a. Table 8, Chapter 9

b. Table 250.66

c. Table 250.102(C)(1)

d. Table 250.122

Table 250.102(C)(1)

The grounded neutral conductor serves which two purposes for a grounded service?I. Carries the maximum load of the ungrounded conductors suppliedII. Carries the maximum unbalanced return neutral loadIII. Connects the system directly to earthIV. Provides a conductive path to the grounding electrode systemV. Serves as an effective ground-fault current path in ground fault conditions

Select one:

a. I. and II.

b. II. and III.

c. II. and V.

d. III. and IV.

: II. and V.

If a main bonding jumper is a screw, the screw is always required to be identified using the color green.

true

The ? is a conductor connected to the neutral point of a system that is intended to carry current under normal conditions.

Select one:

a. equipment grounding conductor

b. grounding electrode conductor

c. main bonding jumper

d. neutral conductor

neutral conductor

For a grounded service, the ? is the intentionally constructed, low-impedance, effective ground-fault current path addressed in 250.4(A).

Select one:

a. equipment grounding conductor

b. grounded conductor

c. system bonding jumper

d. ungrounded conductor

grounded conductor

Which of the following characteristics are required for ungrounded conductors installed in parallel?I. Must be not smaller than 1/0 AWG (generally)II. Must be the same colorIII. Must be the same conductor materialIV. Must be the same insulation typeV. Must be the same lengthVI. Must be the same sizeVII. Must be terminated in the same manner

Select one:

a. I., III., and IV.

b. I., III., IV., V., VI., and VII.

c. All of the above

d. None of the above

I., III., IV., V., VI., and VII.

Grounding connections to the grounded conductor are generally not permitted on the load side of the service equipment enclosure.

true

A grounded conductor (often the neutral) larger than 6 AWG is required to be identified by which of the following methods?

Select one:

a. A bare conductor that is part of a listed service-entrance cable assembly

b. A continuous white or gray outer finish

c. A distinctive white or gray marking at terminations that encircles the conductor

d. Three continuous white or gray stripes along its entire length on other than green insulation

e. Any of the above

any of the above

The service disconnecting means used for a grounded supply system is required to be listed as suitable for use as service equipment.

true

Service equipment that is listed as suitable for use only as service equipment always includes a main bonding jumper.

false

The NEC requires that a(n) ? be provided in the grounded conductor for service equipment.

Select one:

a. circuit breaker

b. disconnecting means

c. fuse

d. overload device

disconnecting means

If a service switchboard is supplied from an ungrounded 240-volt system, which of the following markings are required on the switchboard?

Select one:

a. Caution: Ungrounded System

b. Caution: Ungrounded System Operating 240 Volts Between Conductors

c. System Is Ungrounded 240 Volts

d. Ungrounded System

e. Any of the above

Caution: Ungrounded System Operating 240 Volts Between Conductors

The NEC generally requires all metal enclosures and raceways for service conductors to be grounded except for metal components such as metal elbows in a run of nonmetallic service raceway that are isolated from contact by persons by not less than ? of cover to any part of the elbow.

a. 6"

b. 18"

c. 24"

d. 36"

18"

Ground detectors are required to be installed on services supplied by ungrounded systems, and the ground detection sensing equipment must be connected as close as practicable to the service or source.

true

If the size of the largest ungrounded service conductor for a service is 3,600 kcmil (six 600 kcmil conductors in parallel per phase), what is the minimum-size copper wire-type main bonding jumper required?

Select one:

a. 3/0 copper

b. 300 kcmil copper

c. 400 kcmil copper

d. 500 kcmil copper

Note: Review sizing methods for the 12.5% rule when the size of the largest ungrounded service conductor exceeds the values in Table 250.102(C)(1). Use of Table 8, Chapter 9 should be reviewed.

3600 x 12.5% = 450 kcmil

Take that value to Table 8 in the left column and find that the minimum kcmil required is 450 (larger than 400 kcmil), then round up to 500 kcmil copper.

The correct answer is: 500 kcmil copper

Because in-ground swimming pools provide an excellent grounding connection to the earth, when they are installed on a property, they are required to be included in, and bonded to, the grounding electrode system installed for a building or structure served.

false

Where the utility transformer supplying the service is located outside the building or structure served, at least one additional grounding connection shall be made from the grounded service conductor to a grounding electrode at which of the following locations?

Select one:

a. At the transformer

b. Elsewhere outside the building

c. Inside the building nearest the point of entrance of the service conductors

d. Either a. or b.

Either a. or b.

Which of the following materials are permitted for use as main and system bonding jumpers?

Select one:

a. Aluminum

b. Copper

c. Copper-clad aluminum

d. All of the above

All of the above