UNEC 225

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The point of attachment of overhead premises wiring to a building shall in no case be less than _____ ft above finished grade.

10

Open individual conductors shall not be smaller than _____ AWG copper for spans up to 50 ft in length and _____ AWG copper for a longer span, unless supported by a messenger wire.

10, 8

Overhead feeder conductors shall have a minimum _____ ft vertical clearance over residential property and driveways, as well as those commercial areas not subject to truck traffic, where the voltage does not exceed 300 volts-to-ground.

12

The minimum clearance for overhead feeder conductors that pass over track rails of railroads is _____ ft.

24.5

Outside branch circuits and feeders shall not be installed beneath openings through which materials may be moved, and shall not be installed where they will obstruct entrance to these buildings' openings.

True

The type of disconnecting means specified in 225.31 shall be comprised of a circuit breaker, molded case switch, general-use switch, snap switch, or other approved means.

True

Raceways entering from outside shall be sealed with a product identified for use with the _____ insulation.

a or b

Underground raceways entering a _____ from outside shall be sealed.

a or b

Raceways on exteriors of buildings or other structures shall be arranged to drain and shall be _____ for use in wet locations.

b or c

Overhead feeder and/or branch-circuit conductors shall not be attached to a mast where the connection is _____ a weatherhead or the end of the conduit and a coupling where the coupling is located above the last point of securement to the building or other structure, or where the coupling is located above the building or other structure.

between

The two to six disconnects for a disconnecting means for a building supplied by a feeder shall be _____.

grouped

The disconnecting means for a building supplied by a feeder shall be installed at a(n) _____ location.

readily accessible

There shall be no more than _____ switches or circuit breakers to serve as the disconnecting means for a building supplied by a feeder.

six

In a multiple-occupancy building, each occupant shall have access to his or her own _____.

supply disconnecting means

The requirement for maintaining a 3-foot vertical clearance from the edge of the roof shall not apply to the final feeder conductor span where the conductors are attached to _____.

the side of a building

A building disconnecting means that supplies only limited loads of a single branch circuit shall have a rating of not less than _____.

15A

The minimum clearance for overhead feeder conductors not exceeding 1,000V that pass over commercial areas subject to truck traffic is _____ ft.

18

The vertical clearance of final spans of overhead conductors above or within _____ ft measured horizontally of platforms, projections, or surfaces that will permit personal contact shall be maintained in accordance with 225.18.

3

Overhead feeder conductors installed over roofs shall have a vertical clearance of not less than _____ above the roof surface, unless otherwise permitted by an exception.

8 ft 6 in.

If a set of 120/240V overhead feeder conductors terminates at a through-the-roof raceway or approved support, with not more than 6 ft of these conductors, 4 ft horizontally, passing over the roof overhang, the minimum clearance above the roof for these conductors is not less than _____.

18 in.

The disconnecting means for a building supplied by a feeder shall plainly indicate whether it is in the _____ position.

open or closed

Where a mast is used for overhead branch-circuit or feeder conductor support, it shall have adequate strength or be supported by braces or guys to safely withstand the strain imposed by the conductors.

True

A building or structure shall be supplied by a maximum of _____ feeder(s) or branch circuit(s), unless specifically permitted otherwise.

one

Vegetation such as trees shall not be used for support of _____.

overhead conductor spans

When the disconnecting means for a building supplied by a feeder is a power-operable switch or circuit breaker, it shall be able to be opened by hand in the event of a _____.

power failure

Where documented safe switching procedures are established and maintained and the installation is monitored by _____ individuals, the disconnecting means for a building supplied by a feeder can be located elsewhere on the premises.

qualified

For installations consisting of not more than two 2-wire branch circuits, the building disconnecting means shall have a rating of not less than _____.

30A


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