424.4
Plug fuses and fuseholders can be used in circuits supplied by a system having a grounded neutral point and having no conductor at over ___ volts to ground.
150
What size copper grounding electrode conductor is required for a 1500 kcmil copper service conductor?
3/0 AWG
Inverse time circuit breakers that have an interrupting rating other than ___ amperes, shall have the interrupting rating indicated on the breaker.
5,000
Electrodes of steel or iron shall have a diameter of at least ___.
5/8"
The largest standard rating for an inverse time circuit breaker is ___ amperes.
6000
Which of the following is a standard size fuse?
601
Which of the following is not a true statement per the National Electrical Code?
Under certain conditions, equipment grounding conductors shall be required to be larger than the circuit conductors supplying the equipment
To ensure effective continuity between enclosures, ___ shall be removed from the conduit threads.
enamel
A ___ is used to connect the grounding electrode to the equipment or to the grounded conductor at the service equipment.
grounding electrode conductor
Plug fuses of the Edison-base type shall be used ___.
only as a replacement in existing installations
A 600-amp main breaker service panelboard is fed with four parallel sets of 1/0 kcmil copper. What is the smallest copper grounding electrode conductor that can be installed to the steel structure?
1/0 AWG
Where used outside, aluminum or copper-clad aluminum grounding conductors shall not be terminated within ___ inches of earth.
18
A two-pole circuit breaker that may be used for protecting a 3 phase, corner-grounded delta circuit shall be marked ___.
1Ø 143Ø
When an electrical service is required to have a grounded conductor present, what is the smallest grounded conductor permitted for an electric service using 1000 kcmil copper ungrounded conductors?
2/0 copper
A grounding ring encircling the building, in direct contact with the earth, must consist of at least ___ feet of bare copper conductor not smaller than 2 AWG.
20
A single, made grounding electrode shall have a maximum resistance to ground of ___ ohms.
25
An equipment bonding jumper on the supply side of the service must not be smaller than the sizes shown in Table ___.
250.102(C)(1)
A dwelling has a 225-ampere service that is fed with THW copper conductors. The minimum size copper grounding electrode conductor to the metal water pipe is ___ AWG.
4
A single family dwelling has a 200-amp, 120/240-volt, single-phase, main service panel and is being fed with 2/0 AWG THW copper ungrounded service entrance conductors in rigid metal conduit. The minimum allowable size of the MBJ for this service entrance conduit is ___.
4 AWG
Given: A metal underground water pipe is used as a grounding electrode and used to bond other electrodes together. The grounding electrode conductor is connected to the water pipe on the interior of the building. The connection of the grounding electrode conductor to the interior water pipe shall be made a maximum of ___ feet from the point where the water pipe enters the building.
5
Where more than one grounding electrode is used, each electrode of one grounding system (including that used for air terminals) shall not be less than ___ feet from any other electrode of another grounding system.
6
A single electrode consisting of a ___ which does not have a resistance to ground of 25 ohms or less shall be augmented by one additional electrode.I. rod II. pipe III. plate
I, II or III
A grounding electrode conductor shall not be required for a system that supplies a ___ circuit and is derived from a transformer not more than 1000 VA. I. Class 1 II. Class 2 III. Class 3
I, II, and II
Circuit breakers shall be marked with their ampere rating in a manner that will be ___ after installation. I. accessible II. durable III. visible
II & III only
Overcurrent devices shall be enclosed in ___. I. cabinets II. cutout boxes
either I or II
A current-limiting overcurrent protective device is a device that will ___ the current flowing in the faulted circuit.
reduce
Given: You have tenant spaces in a mall; each occupant shall have access to the main disconnecting means, except where ___.
the service and maintenance are provided by the building management
