Mid-Term Exam Flashcards
A Class I circuit conductor shall have a minimum insulation rating of how many volts?
600 Volts
NEC Article 725 Class I Circuits - 725.41 - 725.49B
A metal water pipe that runs underground can serve as a grounding electrode if it is in direct contact with the earth for at LEAST _____ feet or more.
10FT
NEC Index - Grounding/Electrodes - 250 Part III - Grounding Electrode 250.30A4 - 250.52A1
A method for finding total resistance of a parallel circuit is the _____ formula.
All of the above.
?
An electric motor is running on 120 V. The current is measured to be 2A. How many OHMS of resistance is the motor?
60 OHMS
?
And electrical circuit has a voltage of 50 V and a resistant of 5 OHMS. What is the value of the current?
10A
?
An opposition to current flow that occurs in alternating current circuits is called ____.
A Current
?
Current that flows in only one direction is called Unidirectional. It is also referred to as _____ current.
Direct Current
?
Electron flow theory states that current flows from the most negative point in the current to the most positive point in the circuit. This is due to the fact that electrons are _____ particles.
Moving
?
Fire alarm cable must be protected by a metal raceway or rigid nonmetallic conduit up to what height from the floor?
7FT
?
Fire alarm circuits and equipment shall be grounded _____.
In accordance with Article 250.
?
For conductors not in enclosures or hoistways, Power limited fire alarm cable shall be separated from electric light and power, Class I and NPLFA cables Buy a minimum of _____.
2in
?
Given a parallel circuit with 3 resistors, each measuring 15 OHMS, what is the total resistance of the circuit?
5 OHMS
?
Given a series circuit with 3 resistors, each measuring 20 OHMS, what is the total resistance of the circuit?
60 OHMS
?
Grounding conductors for equipment shall be what color?
Green, Green Stripped with one or more Yellow stripes, or Bare/Copper.
(?)
If one of the parallel paths is broken, current will not continue to flow in any path.
False
?
In a parallel circuit, the total resistance is _____ value resistance.
Smaller than the smallest
?
In a series circuit the amperage at any point in the circuit is the same.
True
?
In order to have current flow, circuit must be _____.
Closed.
?
Non-power limited fire alarm cable shall have an insulation rating of not less than_____.
600 Volts.
?
Of the following cable types, which of the following may not be used as a power limited riser cable?
CL3
?
Opposition to current flow is called_____.
Resistance.
?
Power limit a fire alarm cable installed in hoistways shall be installed in_____.
Rigid Metal Conduit.
?
Power sources for power limited fire alarm circuits must be protected by an overcurrent device not rated at more than _____.
20 AMPS
?
The accessible portion of abandoned fire alarm cable must be _____.
Removed.
?
The AHJ has required you to remove the fire alarm cable installed above the drop ceiling because it is not appropriate for an environmental airspace. What type of cable should your supervisor order to replace the cable you are removing?
FPLP
?
The grounding electrode system may be any of the following except _____.
A fire sprinkler lateral at least 2 inches in diameter.
?
The sum of the currents through each path is equal to the total current that flows from the source.
True.
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