Article 240 Quiz

If the circuit's overcurrent device exceeds _____, the conductor ampacity shall have a rating not less than the rating of the overcurrent device. "800A, 1000A, 1200A, or 2000A"

800A

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, Close, Monitor or Record"

Open

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

True

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

True

Circuit breakers shall _____ all ungrounded conductors of the circuit both manually and automatically unless specifically permitted otherwise. a) open b)close c)isolate d)inhibit

a) open

A circuit breaker having an interrupting current rating of other than _____ shall have its interrupting rating marked on the circuit breaker. a)5,000A b)10,000A c)22,000A d)50,000A

a)5,000A

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. a)straight b)slash c)high d)low

a)straight

_____ shall not be located over the steps of a stairway. a)Disconnect switches b)Overcurrent devices c)Knife switches d)Transformers

b)Overcurrent devices

Plug fuses of the Edison-base type shall be used only _____. a)where over fusing is necessary b)as a replacement in existing installations c)as a replacement for Type S fuses d)if rated 50A and above

b)as a replacement in existing installations

Circuit breaker enclosures shall be permitted to be installed _____ where the circuit breaker is installed in accordance with 240.81 a)vertically b)horizontally c)face up d)face down

b)horizontally

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. a)straight b)slash c)high d)low

b)slash

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. a) 2ft b) 4 ft 6 in c) 5ft d) 6ft 7 in

d) 6ft 7 in

Fuses shall be marked with their _____. a) ampere and voltage rating b) interrupting rating where other than 10,000A c)name or trademark of the manufacturer d) all of these

d) all of these

Overcurrent protection shall not exceed _____. a) 15A for 14 AWG copper b) 20A for 12 AWG copper c) 30A for 10 AWG copper d) all of these

d) 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 _____. a)conductors being protected are not part of a branch circuit supplying more than one receptacle for cord-and-plug-connected portable loads b) ampacity of the conductors does not correspond with the standard ampere rating of a fuse or circuit breaker c)next higher standard rating selected does not exceed 800A d)all of these

d) all of these

Overcurrent devices are not permitted to be located in the bathrooms of _____. a)dwelling units b)dormitories c)guest rooms or guest suites of hotels or motels d)all of these

d)all of these

Overcurrent devices shall not be located _____. a)where exposed to physical damage b)near easily ignitible materials, such as in clothes closets c)in bathrooms of dwelling units d)all of these

d)all of these