Mike Holt Article 240

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Outside secondary conductors can be of unlimited length without overcurrent protection at the point they receive their supply if the conductors _____.

all of these

Overcurrent devices are not permitted to be located in the bathrooms of _____.

all of these

Overcurrent devices shall not be located _____.

all of these

Overcurrent protection shall not exceed _____.

all of these

Tap conductors not over 25 ft in length shall be permitted, providing the _____.

all of these

The next higher standard rating overcurrent device above the ampacity of the ungrounded conductors being protected shall be permitted to be used, provided the _____.

all of these

The standard ampere ratings for fuses include(s) _____.

all of these

Plug fuses of the Edison-base type shall be used only _____.

as a replacement in existing installations

Fuseholders for cartridge fuses shall be so designed that it is difficult to put a fuse of any given class into a fuseholder that is designed for a _____ lower or a _____ higher than that of the class to which the fuse belongs.

current, voltage

A circuit breaker with a slash rating, such as 120/240V or 480Y/277V, shall be permitted to be applied in a solidly grounded circuit where the nominal voltage of any conductor to ground _____ the lower of the two values of the circuit breaker's voltage rating and the nominal voltage between any two conductors _____ the higher value of the circuit breaker's voltage rating.

does not exceed

Reconditioned circuit breakers shall be listed as “reconditioned†and the original listing mark shall be _____.

removed

When taps are not over 10 ft in length for field installations, and they leave the enclosure or vault in which the tap is made, the ampacity of the tap conductors cannot be less than _____ the rating of the device protecting the feeder.

1/10

Circuit breakers and switches containing fuses shall be readily accessible and installed so the center of the grip of the operating handle of the switch or circuit breaker, when in its highest position, is not more than _____ above the floor or working platform.

6 ft 7 in.

If the circuit's overcurrent device exceeds _____, the conductor ampacity shall have a rating not less than the rating of the overcurrent device.

800A

_____ shall not be located over the steps of a stairway.

Overcurrent devices

Circuit breakers used to switch 120V and 277V fluorescent lighting circuits shall be listed and marked _____.

SWD or HID

Feeder taps are permitted to be located at any point on the load side of the feeder overcurrent protective device.

True

The arc energy reduction protection system shall be performance tested when first installed by _____ in accordance with the manufacturer.

a qualified person(s)

Fuses shall be marked with their _____.

all of these

Only _____ circuit breakers shall be permitted to be reconditioned.

all of these

Outside feeder tap conductors can be of unlimited length without overcurrent protection at the point they receive their supply if the tap conductors _____.

all of these

For adjustable-trip circuit breakers, restricted access is defined as _____.

any of these

Cartridge fuses in circuits of _____, and all fuses in circuits over 150 volts to ground, shall be provided with a disconnecting means on their supply side so that each circuit containing fuses can be independently disconnected from the source of power.

any voltage

Where a method to reduce clearing time for fuses rated 1,200A or greater is required in accordance with 240.67(B), the _____ reduction system shall be performance tested when first installed on site.

arc energy

Conductor overload protection shall not be required where the interruption of the _____ would create a hazard, such as in a material-handling magnet circuit or fire pump circuit. However, short-circuit protection is required.

circuit

A device that, when interrupting currents in its current-limiting range, reduces the current flowing in the faulted circuit to a magnitude substantially less than that obtainable in the same circuit if the device were replaced with a solid conductor having comparable impedance, is a(an) "_____ protective device."

current-limiting overcurrent

Circuit breaker enclosures shall be permitted to be installed _____ where the circuit breaker is installed in accordance with 240.81

horizontally

Supplementary overcurrent protection _____.

may be used to protect internal circuits of equipment

A conductor, other than a service conductor, that has overcurrent protection ahead of its point of supply that exceeds the ampacity permitted for similar conductors is known as a _____.

tap conductor

Ground-fault protection of equipment shall be provided for solidly grounded wye electrical systems of more than 150 volts-to-ground, but not exceeding 1,000V phase-to-phase for each individual device used as a building or structure main disconnecting means rated _____ or more, unless specifically exempted.

1,000A

The general requirements for overcurrent protection and overcurrent protective devices not more than 1,000V, nominal are provided in Article _____.

240

Plug fuses of the Edison-base type shall have a maximum rating of _____.

30A

A circuit breaker having an interrupting current rating of other than _____ shall have its interrupting rating marked on the circuit breaker.

5,000A

Conductors supplied under the tap rules are allowed to supply another conductor using the tap rules.

False

Molded-case circuit breakers are permitted to be reconditioned.

False

Circuit breakers used to switch high-intensity discharge lighting circuits shall be listed and marked as _____.

HID

Single-pole breakers with identified handle ties can be used to protect each ungrounded conductor for line-to-line connected loads.

True

Supplementary overcurrent devices used in luminaires or appliances are not required to be readily accessible.

True

Where the circuit breaker handles are operated vertically, the "up" position of the handle shall be the "_____" position.

on

Circuit breakers shall _____ all ungrounded conductors of the circuit both manually and automatically unless specifically permitted otherwise.

open

Overcurrent protection for conductors and equipment is provided to _____ the circuit if the current reaches a value that will cause an excessive or dangerous temperature in conductors or conductor insulation.

open

A circuit breaker with a _____ rating, such as 120/240V or 277/480V can be used on a solidly grounded circuit where the nominal voltage of any conductor to ground does not exceed the lower of the two values, and the nominal voltage between any two conductors does not exceed the higher value.

slash

A circuit breaker with a _____ voltage rating, such as 240V or 480V, can be used where the nominal voltage between any two conductors does not exceed the circuit breaker voltage rating.

straight


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