IO #7 - Chap. 1-5+7 Flashcards
If a conductive part is connected to ground or to a conductive body that extends a ground connection it is ? .
Grounded
When electrical systems or equipment are grounded, the ground (Earth) is part of the electrical circuit. T/F
True
The frame of an automobile or airplane is not grounded. T/F
True
The conductive object directly connected to Earth through which grounding is established, is the ?.
Grounding Electrode
A(n) ? occurs when electrical current in a circuit returns through the equipment grounding conductor (EGC), through conductive material other than the electrical system ground (metal, water pipes, and so forth), through a person or through a combination of these ground return paths.
Ground Fault
An unintentional, electrically conducting connection between an ungrounded conductor of an electrical circuit and the normally non–current-carrying conductors, metallic enclosures, metallic raceways, metallic equipment, or Earth best defines which of the following?
Ground Fault
Not connected to ground or to a conductive body that extends the ground connection
Ungrounded
The frame of an automobile is typically the ? of the vehicle electrical system.
Negative side
What is the phase-to-ground voltage of a corner grounded 480-volt, 3-phase, 3-wire, delta-connected system?
480V
In a 60-cycle AC circuit, the voltage and current change amplitude and direction ? times per second.
120
Fuses and circuit breakers are required to be marked with all but which of the following ratings? Select one: a. Ampere interrupting current rating b. Normal current rating c. Resistance d. Voltage
c. Resistance
The ? of an electrical system is the maximum current a system is capable of delivering at any point on the wiring installation.
Available Fault Current
An unintentional conducting connection between two ungrounded conductors of a circuit is a ?.
Short Circuit
Inverse time operation of overcurrent devices means that the ? the current, the ? the device will react to the ground fault or short circuit event.
Higher / Faster
Which of the following organizations developed the formulas to determine insulated and bare conductor current withstand ratings?
Select one:
a. General Cable Company
b. Insulated Cable Engineers Association (ICEA)
c. International Association of Electrical Inspectors (IAEI)
d. International Code Council (ICC)
b. Insulated Cable Engineers Association (ICEA)
Which NEC table provides the minimum sizes for wire-type equipment grounding conductors?
250.122
Which of the following test instruments is commonly used to determine the integrity of conductor insulation?
Megohmmeter
Wire-type equipment grounding conductors expressed in Table 250.122 of the NEC are approximately ? of the circuit conductor size. Select one: a. 20% b. 25% c. 50% d. 100%
b. 25%
Applying an overcurrent device (fuse or circuit breaker) within its marked interrupting rating will ensure that the overcurrent device can safely open the circuit in a ground fault condition. T/F
True
A(n) ? is defined as a reliable conductor that ensures continuity and conductivity between metal parts required to be electrically connected.
Bonding conductor or Jumper
A grounded conductor of a system could be a ? conductor or a phase conductor.
Neutral
Which of the following is NOT permitted to be used to identify a grounded conductor? Select one: a. Bare conductor of Type SEU cable b. Gray c. Green d. White
c. Green
? of Article 250 specifically applies to grounding systems and circuits over 1,000 volts.
Part X
What is the largest size aluminum grounding electrode conductor required by the NEC?
250kcmil
