| 1. | In Class 1, Division 1 locations, conduit seals shall be placed a maximum
of ______inches from an enclosures containing arc producing equipment. | |
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| a) | 12
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| b) | 18
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| c) | 24
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| d) | 30
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| 2. | What length is required for the pullbox in the diagram below? The box is used with 480 volt conductors
that are not spliced. |
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| a) | 32 inches
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| b) | 24 inches
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| c) | 48 inches
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| d) | any length
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| 3. | What is the load that can be used for the service calculation for
a dwelling unit when the Range has a nameplate rating of 13 KW? |
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| a) | 13 kw
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| b) | 8.4 kw
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| c) | 8 kw
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| d) | none of the above
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| 4. | What size
copper equipment grounding conductor is required for a circuit protected with a 50 ampere circuit breaker? |
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| a) | No. 12 copper
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| b) | No. 10 copper
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| c) | No. 8 copper
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| 5. | What is the highest voltage
permitted for a Class 1 power limited circuit? |
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| a) | 1,000 volts
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| b) | 30 volts
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| c) | 24 volts
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| d) | None of the above
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| 6. | What is the missing voltage in the sketch below? |
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| a) | 120 volts
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| b) | 120 volt's
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| c) | 1200 volts
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| d) | 12,000 volts
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| 7. | What
is the minimum size 10 feet long Rigid Metal conduit
required for the following 9 conductors?
4 THWN #12 CU, 2 RHW (covered) #8 CU, 3 RHW (covered) #6 CU |
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| a) | 1 1/2 inch
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| b) |
2 inch
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| c) |
1 1/4 inch
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| d) | None of the above
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| 8. | What is the efficiency of a motor which draws 4.5 kilowatts from the line and delivers 5 horsepower? |
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| a) | 80 percent
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| b) | 83 percent
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| c) | 90 percent
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| 9. | Power Factor can be defined as: |
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| a) | True Power divided by Apparent Power
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| b) | Apparent Power divided by True Power
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| c) | Apparent Power divided by volts x amperes
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| 10. | What is the power factor for a three phase system operating when the
wattmeter reads 6,000 watts, the voltmeter reads 208 volts, and the ammeter
reads 20 amperes? |
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| a) | .90 or 90 percent
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| b) | 1.04 or 104 percent
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| c) | .83 or 83 percent
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| 11. | What is the power factor
for a 8000 watt load connected to a 240 volt AC single-phase circuit if the current is 36 amperes? |
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| a) | .8 or 80 percent
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| b) | .93 or 93 percent
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| c) | 1.0 or 100 percent
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| 12. | For the figure below if No. 4 or larger conductors are installed
in the raceways dimension X shall be ____inches minimum. The box is used
for splices and doe not have the cubic inch dimensions marked on it. |
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| a) | 18 inches
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| b) | 16 inches
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| c) | 24 inches
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| 13. | For the 4-way Switch, which is the correct hookup? |
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| a) | D to T, E to R, F to T, G to S
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| b) | D to S, E to R, F to T, G to W
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| c) | D to R, E to T, F to S, G to W
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| 14. | | A dwelling has a floor area of 2200 sq. ft., exclusive
of an unfinished cellar not adaptable for future use, unfinished attic,
and open porches. Appliances are a 12-kW range and a 5.5-kW, 240-V dryer.
Assume range and dryer kW ratings equivalent to kVA ratings in accordance
with Sections 220-18 and 220-19.Computed Load [see Section 220-10] | | | | Fill in the following information: | | | | General Lighting Load: _____ sq. ft. at __ VA per sq.
ft. =_______ VA Minimum | | | | Number of Branch Circuits Required: | General Lighting Load: ______ VA / 120 V = ___ A
General Lighting Load: ______ VA / 120 V = ___ A
This requires______ 15-A, 2-wire or______ 20-A, 2-wire circuits
Small Appliance Load: _____ 2-wire, 20-A circuits
Laundry Load :One 2-wire, 20-A circuitOne additional bathroom 20 ampere circuit is also required. | | | | Minimum Size Feeder Required : | General Lighting _______ VA
Small Appliance ______ VA
Laundry ______ VA
Total 11100 VA
______ VA at 100% 3000 VA
_______ VA - 3000 VA =______ VA at _____% is ______ VA
Net Load _______ VA
Range ______ VA
Dryer________ VA
Net Computed Load _______ VA
Net Computed Load for 120/240-V, 3-wire, single-phase service or feeder
________ VA / 240 V = ______ A
Net computed load exceeds 10 kVA. Would require service
conductors to be _____ A.
| | Calculation for Neutral for Feeder and Service: |
Lighting and Small Appliance Net Load _____ VA
Range: _____ VA at 70% is 5600 VA
Dryer : _______ VA at 70% is ______ VA
Total ________ VA | | Computed Load for Neutral: | __________ VA / 240 V = ______ A | | |
What is the final computed load for the neutral in the above load calculation? |
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| a) | 65.9
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| b) | 63.7
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| c) | 100
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| d) | 111
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| 15. | The correct hookup for the 3-way switch below is: |
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| a) | A to X, B to Z, C to Y
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| b) | A to Y, B to X, C to Z
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| c) | A to Z, B to Y, C to X
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| d) | A to Z, B to X, C to Y
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| 16. | Connect the delta wound 480 volt motor leads for the high voltage windings in the diagram below. |
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| a) | 9-7, 4-6, 8-9, 5-4
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| b) | 4-7, 5-8, 6-9
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| c) | 4-9, 6-8, 5-7
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| 17. | Find the correct size ventilated cable tray for the diagram below. |
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| a) | 6 inches
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| b) | 12 inches
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| c) | 18 inches
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| d) | 24 inches
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| 18. | Find the voltage across the 5 ampere load after the neutral is opened. Both loads are resistive and the power factor is 1.0. |
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| a) | 180 volts
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| b) | 120 volts
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| c) | 0 volts
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| 19. | Find the size of inverse time circuit breaker required for the feeder
protecting the following polyphase induction motors. These motors are Design
B and have a Service Factor of 1.15 and are individually protected with inverse
time circuit breakers. |
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| a) | 150 ampere
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| b) | 175 ampere
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| c) | 200 ampere
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| 20. | How many cubic inches is required for the following box? All conductors are No. 14 and there are no internal clamps. |
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| a) | 12 cubic inches
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| b) | 16 cubic inches
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| c) | 18 cubic inches
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| d) | 20 cubic inches
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