B&G Chptr 2. 3,4,5

Auxiliary grounding electrodes can be connected to the _____.

equipment grounding conductor. 250.54

Bare aluminum or copper-clad aluminum grounding electrode conductors shall not be used where in direct contact with _____ or where subject to corrosive conditions.

masonry or the earth. 250.64(A)

Swimming pool structures and structural _____ [680.26(B)(1) and (B)(2)] shall not be used as a grounding electrode.

reinforcing steel. 250.52(B)(3)

Grounding electrodes of bare or electrically conductive coated iron or steel plates shall be at least _____ in. thick.

1/4. 250.52(A)(7)

Ground rod electrodes shall be installed so that at least _____ of the length is in contact with the soil.

8 ft. 250.53(G)

Two or more grounding electrodes bonded together are considered a single grounding electrode system.

True. 250.53(b) and 250.58

A grounding electrode conductor shall be permitted to be run to any convenient grounding electrode available in the grounding electrode system where the other electrode(s), if any, is connected by bonding jumpers that are installed in accordance with 250.53(C).

True. 250.64(F)(1)

Concrete-encased electrodes of _____ shall not be required to be part of the grounding electrode system where the steel reinforcing bars or rods aren't accessible for use without disturbing the concrete.

existing buildings or structures. 250.50 Ex

Buildings or structures supplied by multiple services or feeders shall use the same _____ to ground enclosures and equipment in or on that building.

grounding electrode system. 250.58

Grounding electrode conductors and grounding electrode bonding jumpers in contact with _____ shall not be required to comply with 300.5, but shall be buried or otherwise protected if subject to physical damage.

the earth. 250.64(B)(4)

Where the resistance-to-ground of 25 ohms or less is not achieved for a single rod electrode, _____.

the single rod electrode shall be supplemented by one additional electrode. 250.53(A)(2) Ex

If a building or structure is supplied by a service or feeder with _____ or more disconnecting means in separate enclosures, the grounding electrode connections shall be made in accordance with 250.64(D)(1), 250.64(D)(2), or 250.64(D)(3).

two. 250.64(D)

Bonding jumper(s) from grounding electrode(s) shall be permitted to be connected to an aluminum or copper busbar not less than _____ and of sufficient length to accommodate the number of terminations necessary for the installation in accordance with 250.64(F).

1/4 in. thick × 2 in. wide. 250.64(F)(3)

In order for a metal underground water pipe to be used as a grounding electrode, it shall be in direct contact with the earth for _____.

10 ft or more. 250.52(A)(1)

One or more metal in-ground support structure(s) in direct contact with the earth vertically for _____ ft or more, with or without concrete en-casement is permitted to be a grounding electrode in accordance with 250.52.

10. 250.52(A)(2)

What size copper grounding electrode conductor is required for a service that has three sets of 600 kcmil copper conductors per phase?

3/0 AWG. 250.66 and Table 250.66

When a ground ring is used as a grounding electrode, it shall be installed at a depth below the earth's surface of not less than _____.

30 in. 250.53(F)

Where rock bottom is encountered when driving a ground rod at an angle up to 45 degrees, the electrode can be buried in a trench that is at least _____ deep.

30 in. 250.53(G)

Grounding electrodes of the rod type less than _____ in diameter shall be listed.

5/8 in. 250.52(A)(5)(b)

Where the supplemental electrode is a rod, that portion of the bonding jumper that is the sole connection to the supplemental grounding electrode shall not be required to be larger than _____ AWG copper wire.

6. 250.53(E)

Grounding electrode conductors _____ AWG and larger that are not exposed to physical damage can be run along the surface of the building construction without metal covering or protection.

6. 250.64(B)(1)

Grounding electrode conductors smaller than _____ AWG shall be protected in rigid metal conduit, IMC, PVC conduit, electrical metallic tubing, or cable armor.

6. 250.64(B)(3)

If the grounding electrode conductor or bonding jumper connected to a single or multiple rod, pipe, or plate electrode(s), or any combination thereof, as described in 250.52(A)(5) or (A)(7), does not extend on to other types of electrodes that require a larger size conductor, the grounding electrode conductor shall not be required to be larger than _____ AWG copper wire.

6. 250.66(A)

The grounding electrode used for grounding strike termination devices of a lightning protection system can be used as a grounding electrode system for the buildings or structures.

False. 250.60

An encased or buried connection to a concrete-encased, driven, or buried grounding electrode shall be accessible.

False. 250.68(A) Ex 1

The connection of the grounding electrode conductor to a buried grounding electrode (driven ground rod) shall be made with a listed terminal device that is accessible.

False. 250.68(A) Ex 1

Where more than one concrete-encased electrode is present at a building or structure, it shall be permitted to bond to only one into the grounding electrode system.

True. 250.52(A)(3)

Reinforcing bars for use as a concrete-encased electrode can be bonded together by the usual steel tie wires or other effective means.

True. 250.52(A)(3)(1)

When installing auxiliary electrodes, the earth shall not be used as an effective ground-fault current path.

True. 250.54

Grounding electrode conductors that are not subject to physical damage can be run exposed along the surface of the building construction if securely fastened to the surface on which they are carried.

True. 250.64(B)

Ferrous metal raceways and enclosures for grounding electrode conductors shall be electrically continuous from the point of attachment to cabinets or equipment to the grounding electrode.

True. 250.64(E)(1)

Exothermic or irreversible compression connections, together with the mechanical means used to attach to fireproofed structural metal, shall not be required to be accessible.

True. 250.68(A) Ex 2

When an underground metal water piping system is used as a grounding electrode, bonding shall be provided around insulated joints and around any equipment that is likely to be disconnected for repairs or replacement.

True. 250.68(B)

Local metal underground systems or structures such as _____ are permitted to serve as grounding electrodes.

all of these. 250.52(A)(8)

Where conditions of maintenance and supervision ensure only qualified persons service the installation in _____ buildings, the entire length of the metal water piping system can be used for grounding purposes, provided the entire length, other than short sections passing through walls, floors, or ceilings, is exposed.

all of these. 250.68(C)(1) Ex

Grounding electrode conductors shall be installed in one continuous length without a splice or joint, unless spliced by _____.

any of these. 250.64(C)(1) and (2)

The grounding conductor connection to the grounding electrode shall be made by _____.

any of these. 250.70 and 250.8

Where practicable, rod, pipe, and plate electrodes shall be installed _____.

below permanent moisture level. 250.53(A)(1)

Ferrous metal raceways and enclosures for grounding electrode conductors shall be bonded at each end of the raceway or enclosure to the grounding electrode or grounding electrode conductor to create a(n) _____ parallel path.

electrically. 250.64(E)(1)

A bare 4 AWG copper conductor installed horizontally near the bottom or vertically, and within that portion of a concrete foundation or footing that is in direct contact with the earth, can be used as a grounding electrode when the conductor is at least _____ ft in length.

20. 250.52(A)(3)

The largest size grounding electrode conductor required is _____ copper.

3/0 AWG. 250.66 and Table 250.66

In an ac system, if the size of the grounding electrode conductor or bonding jumper connected to a concrete-encased electrode does not extend on to other types of electrodes that require a larger size of conductor, the grounding electrode conductor shall not be required to be larger than _____ AWG copper.

4. 250.66(B)

An electrode encased by at least 2 in. of concrete, located horizontally near the bottom or vertically and within that portion of a concrete foundation or footing that is in direct contact with the earth, shall be permitted as a grounding electrode when it consists of _____.

a or b. 250.52(A)(3)

Where used outside, aluminum or copper-clad aluminum grounding electrode conductors shall not be terminated within _____ in. of the earth.

18. 250.64(A)

A buried iron or steel plate used as a grounding electrode shall expose not less than _____ sq ft of surface area to exterior soil.

2. 250.52(A)(7)

The metal structural frame of a building shall be permitted to be used as a conductor to interconnect electrodes that are part of the grounding electrode system, or as a grounding electrode conductor. Hold-down bolts securing the structural steel column that are connected to a concrete-encased electrode that complies with 250.52(A)(3) and is located in the support footing or foundation shall be permitted to connect the metal structural frame of a building or structure to the concrete encased grounding electrode.

True. 250.68(C)(2)

Interior metal water piping that is electrically continuous with a metal underground water pipe electrode and is located more than _____ ft from the point of entrance to the building shall not be used as a conductor to interconnect electrodes of the grounding electrode system.

5. 250.68(C)(1)