| 1. |
A branch circuit with two or more outlets must be rated at:
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a)
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The same as the overcurrent device rating
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b)
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15, 20, 30, 40, or 50 amperes
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c)
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15, 20, 25, 30, 40, 50
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| 2. |
The circuit shown in the sketch below has a rating of:
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a)
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30 amperes
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b)
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20 amperes
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c)
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Cannot be determined
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| 3. |
Section 210-19(a) requires that conductors have an ampacity not less than the maximum load to be served and there are no exceptions to this rule.
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a)
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True
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b)
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False
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| 4. |
If branch circuit conductors supply only a continuous load then the allowable ampacity of the conductors before any derating factors are applied shall be based on 125 per cent of the continuous load.
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a)
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True
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b)
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False
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| 5. |
What is the allowable ampacity of a No. 12 copper conductor with Type XHHW-2 insulation where there are only 3 current carrying conductors in a raceway and the ambient temperature is 30 degrees C.?
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a)
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25 amperes
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b)
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30 amperes
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c)
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20 amperes
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| 6. |
The load is 20 amperes continuous and 10 amperes noncontinnous. What load shall be used to select the conductor size before the application of any derating factors?
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a)
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30 amperes
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b)
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35 amperes
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c)
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24 amperes
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| 7. |
In the preceding question if there is no additional information given what size THWN copper conductor shall be used?
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a)
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No. 10
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b)
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No. 8
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| 8. |
The rating of the overcurrent device for a load of 20 amperes continuous load and 10 amperes noncontinuous load shall not be less than:
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a)
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35 amperes
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b)
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30 amperes
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| 9. |
In the proceeding question if the circuit supplies two or more outlets then the circuit rating cannot be less than:
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a)
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40 amperes.
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b)
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35 amperes
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| 10. |
The number 8 THWN copper conductor has a 60 degree ampacity of 40 amperes and can be protected using a 40 ampere circuit breaker.
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a)
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True
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b)
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False
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| 11. |
If we have 20 amperes continuous load and 10 amperes noncontinuous load and there are 4 current carrying conductors in a raceway what size XHHW-2 copper conductor is required?
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a)
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No. 10
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b)
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No. 8
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c)
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No. 6
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| 12. |
Given the following:
1. 40 amperes continuous load.
2. 60 amperes noncontinuous load.
3. 4 current carrying conductors in a raceway.
4. Ambient temperature is 100 degrees F.
5. Terminations and equipment are rated for 75 degrees C.
6. THHN conductor insulation with copper conductors.
7. This circuit is to supply an individual piece of equipment.
What is the correct size conductor and overcurrent protective device for this circuit?
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a)
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No. 1 using a 110 ampere circuit breaker.
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b)
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No. 2 with a 125 ampere circuit breaker
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| 13. |
In the sketch below there are 4 copper No. 12 XHHW-2 current carrying conductors in a raceway longer than 24 inches. What is the ampacity of these conductors if the ambient temperature is 30 degrees C.?
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a)
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30 amperes
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b)
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24amperes
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c)
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25 amperes
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| 14. |
In the last question if the raceway were a nipple no longer than 24 inches what would the ampacity be?
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a)
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24 amperes
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b)
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30 amperes
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c)
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20 amperes
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| 15. |
If the nipple were in an environment where the ambient was 40 degrees C. (104 degrees F.) what would the ambient temperature be?
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a)
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27.3 amperes
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b)
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30 amperes
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c)
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20 amperes
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| 16. |
Although the ampacity may be determined to be more than 20 amperes for an XHHW-2 No. 12 conductor, can the overcurrent protection be more than 20 amperes if there are no specific rules to allow this?
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a)
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No
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b)
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Yes
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| 17. |
What is the ampacity of a No 12 copper conductor with a 60 degree insulation in a 60 degree ambient environment?
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a)
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0 amperes
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b)
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20 amperes
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| 18. |
There are 3-current carrying conductors in each of the 1/2 inch conduits shown below. The conductors are No. 10 to limit the voltage drop. The rating of the circuits is:
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a)
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30 amperes
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b)
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20 amperes
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| 19. |
Although there is no derating of the conductors in the above sketch, there is a continuous load. Therefore, the rating of the overcurrent devices must be 125 per cent of the continuous load. Therefore the load on the 20 ampere circuit breakers is limited to 80 per cent of 20 amperes or ____ amperes.
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a)
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20 amperes
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b)
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16 amperes
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| 20. |
The sketch below shows is the same as the previous sketch except all the conductors leave the panel in the same conduit. The conductors are No. 10 copper with THHN insulation. The load for each branch circuit is limited to how many amperes, and the derated ampacity of the No. 10 conductors is how many amperes?
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a)
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20 and 24 amperes
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b)
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16 and 24 amperes.
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