Article 250

Listed FMC can be used as the equipment grounding conductor if the conduit does not exceed trade size _____.

1 1/4

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

1/2 >WRONG<

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 >WRONG<

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

10 ft.

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. (2 1/2 ft.)

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

5/8

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

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

8 ft

An equipment grounding conductor shall be identified by _____.

A continuous outer finish that is green with one or more yellow stripes, or just green, or bare copper

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

Below permanent moisture level

True or False: Listed liquidtight flexible metal conduit (LFMC) is acceptable as an equipment grounding conductor when it terminates in listed fittings and is protected by an overcurrent device rated 60A or less for trade sizes 3/8 through 1/2.

False

_____ shall not be used as grounding electrodes.

Metal underground gas piping systems and aluminum

The NEC requires the installation of an equipment grounding conductor of the wire type in _____.

Nothing

Equipment grounding conductors, grounding electrode conductors, and bonding jumpers shall be connected by _____.

Terminal bars, exothermic welding, listed pressure connectors, etc.

True or False: A wire-type equipment grounding conductor is permitted to be used as a grounding electrode conductor if it meets all of the requirements of Parts II, III, and VI of Article 250.

True

True or False: Equipment grounding conductors for feeder taps are not required to be larger than the tap conductors.

True

True or False: Equipment grounding conductors of the wire type shall not be required to be larger than the circuit conductors.

True

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

True

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 _____.

at least 20ft of 1/2 in or larger steel reinforcing bars or rods, or at least 20 ft. of bare copper conductor of 4 AWG or larger

Equipment grounding conductors for motor branch circuits shall be sized in accordance with Table 250.122, based on the rating of the _____ device.

branch-circuit short-circuit and ground-fault protective

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

If circuit conductors are installed in parallel in the same raceway or cable tray, a single wire-type conductor shall be permitted as the equipment grounding conductor and sized in accordance with 250.122, based on the overcurrent protective device for the _____.

feeder or branch circuit

The upper end of a ground rod electrode shall be _____ ground level unless the above ground end and the grounding electrode conductor attachment are protected against physical damage.

flush with or below

Conductors with the color _____ insulation shall not be used for ungrounded or grounded conductors.

green or green with yellow stripes

Ground clamps and fittings that are exposed to physical damage shall be enclosed in _____ or equivalent protective covering.

metal or wood

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

piping systems, underground metal well casing that are not bonded to a metal water pipe, underground tanks

Where a metal underground water pipe is used as a grounding electrode, the continuity of the grounding path or the bonding connection to interior piping shall not rely on _____ and similar equipment.

water meters or filtering devices

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.

Except as provided in 250.122(F)(2)(b) for raceway or cable tray installations, the equipment grounding conductor in each multiconductor cable shall be sized in accordance with 250.122 based on the _____.

Rating of the feeder overcurrent protection device

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

True

True or False: Where circuit conductors are installed in parallel in multiple raceways or cables and include an EGC of the wire type, the equipment grounding conductor shall be installed in parallel in each raceway or cable, sized in compliance with 250.122 based on the overcurrent protective device for the feeder or branch circuit.

True

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

True

Exposed normally noncurrent-carrying metal parts of fixed equipment likely to become energized shall be connected to the equipment grounding conductor where located _____.

in wet or damp locations and not isolated, in electrical contact with metal, and within 8 ft. vertically or 5 ft. horizontally of ground or grounded metal objects and subject to contact by persons

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

reinforcing steel or equipotential planes >WROng<

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

Type MC cable provides an effective ground-fault current path and is recognized by the NEC as an equipment grounding conductor when _____.

it contains an insulated or uninsulated equipment grounding conductor in compliance with 250.118(1) or the combined metallic sheath and uninsulated equipment grounding/bonding conductor of interlocked metal tape-type MC cable is listed and identified as an equipment grounding conductor >WRONG<

When a single equipment grounding conductor is used for multiple circuits in the same raceway, cable, or cable tray, the single equipment grounding conductor shall be sized according to the _____.

largest overcurrent protection device

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

need supplemental electrode

A conductor installed on the supply side of a service or within a service equipment enclosure, or for a separately derived system, to ensure the required electrical conductivity between metal parts required to be electrically connected is known as the "_____."

supply-side bonding jumper

A ground ring encircling the building or structure can be used as a grounding electrode when the _____.

the ring is in direct contact with the earth, its a bare copper conductor not smaller than 2 AWG, and the ring consists of at least 20ft of bare copper conductor

Grounding and bonding connection devices that depend solely on _____ shall not be used.

solder

True or False: The armor of Type AC cable is recognized by the NEC as an equipment grounding conductor.

True

Listed FMC and LFMC shall contain an equipment grounding conductor if the raceway is installed for the reason of _____.

Flexibility after installation or minimizing transmission of vibration from equipment

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

Listed FMC can be used as the equipment grounding conductor if the length in any ground return path does not exceed 6 ft and the circuit conductors contained in the conduit are protected by overcurrent devices rated at _____ or less.

20A

When ungrounded circuit conductors are increased in size to account for voltage drop, the wire-type equipment grounding conductor shall be proportionately increased in size according to the increase in size of the ungrounded conductors using their _____.

circular mil area

_____ on equipment to be grounded shall be removed from contact surfaces to ensure good electrical continuity.

lacquer, paint, enamel, etc.

If multiconductor cables are installed in parallel in the same raceway, auxiliary gutter, or cable tray, _____ equipment grounding conductor(s) that is(are) sized in accordance with 250.122 shall be permitted in combination with the equipment grounding conductors provided within the multiconductor cables and shall all be connected together.

one