Security Installation Formulas Redux
Fire Away: an International Fire Code Refresher
All Answers relate to NFPA 70, 2017 Edition
1. When determining box fill volume allowance, what is the required cu. in. of an 18AWG conductor?
A. 1.5
B. 1.75
C. 2.0
D. 2.25
2. Power over Ethernet (PoE) standard allows voltages up to what maximum?
A. 12
B. 24
C. 48
D. 96
3. Cable certified as Limited-Power (LP) by UL ______.
A. carries a certain load without exceeding the max. temperature rating of the cable
B. lists the maximum voltage permitted
C. cannot exceed 600 volts
D. cannot carry loads that exceed 600mA unless otherwise marked
4. According to the NEC 725.144, conductors that carry power must be ______. (Select all that apply.)
A. copper
B. aluminum
C. gold
D. silver
5. Conductor ampacity reduction is required when ______ or more current-carrying conductors are bundled.
A. 2
B. 3
C. 4
D. 5
6. The cross-sectional area of a conductor is expressed in circular mils. What is the circular mils (cmils) of a 16AWG wire?
A. 1650
B. 2580
C. 3200
D. 4275
7. The resistance of a conductor is ______ proportional to the length.
A. inversely
B. directly
C. relationally
D. reverse
8. “Temperature coefficient” relates to the ______ of a conductor.
A. voltage
B. wattage
C. current
D. resistance
9. The NEC lists dimensions in both American standard and Metric. What is the metric conversion for 1 inch? (select any that are correct.)
A. 0.254 meters
B. 2.54 centimeters
C. 25.4 millimeters
D. 2.54 millimeters
10. The total resistance in a parallel circuit is always ______.
A. the sum of all the resistors
B. less than the smallest resistor
C. equal to the highest resistor in the circuit
D. based on the voltage of the circuit
11. Voltage is always cumulative across each of the parallel resistors.
A. True
B. False
12. Voltage source is equal to the sum of voltage drops of all resistors.
A. True
B. False
13. Raceways that do not exceed ______ may be filled to 60 percent of their total cross-sectional area.
A. 24 in.
B. 6 ft.
C. 10 ft. (standard length of a single stick of conduit)
D. 30 meters
14. What is the cross-sectional area of a nipple that is trade size 2 EMT?
A. 1.456 in.
B. 2.013 in.
C. 4.74 in.
D. 3.2 in.
Feedback: NEC Chapter 9, Note 4
15. The maximum number of conductors permitted in a wireway is limited to ______ percent of the cross-sectional area of the wireway.
A. 20
B. 31
C. 40
D. 53
Feedback: NEC 376.22(A)
Post-Quiz Extra: Can you identify?
Given the information on the diagram, determine the volts, amps and resistance.
Click here to see the answer.
Use #2 as answer
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