Two Minute Drill Number 31- Residential Improving your skill in code Look Up Increasing Speed Drill Copyright 2008 Ted "Smitty" Smith.

Directions Left click on the presentation ICON located at the bottom of the slide directory to the left of the this slide. Left click on the presentation ICON located at the bottom of the slide directory to the left of the this slide. Each slide will transition to the correct answer automatically in 2:00 minutes. The correct answer will transition in 15 seconds. Each slide will transition to the correct answer automatically in 2:00 minutes. The correct answer will transition in 15 seconds. As you progress through the slide show, the time for each question will be reduced. As you progress through the slide show, the time for each question will be reduced. This drill is primarily concerning residential installations. This drill is primarily concerning residential installations. Copyright 2008 Ted "Smitty" Smith

1. For other than single-family dwellings, spas and hot tubs are required to have a clearly labeled emergency shutoff or control switch provided. This switch shall be installed at a point readily accessible to the users and not less than _____ feet and within sight of the spa or hot tub. 1. For other than single-family dwellings, spas and hot tubs are required to have a clearly labeled emergency shutoff or control switch provided. This switch shall be installed at a point readily accessible to the users and not less than _____ feet and within sight of the spa or hot tub. a. 12 b. 10 c. 15 d. 5 Copyright 2008 Ted "Smitty" Smith

2. In a data-processing, room the disconnecting means for the data- processing equipment shall be _____. 2. In a data-processing, room the disconnecting means for the data- processing equipment shall be _____. a. Within sight of the equipment b. Near an exit door c. At the main disconnect d. Within 30 feet of the equipment Copyright 2008 Ted "Smitty" Smith

3. Type MI cable shall be supported at intervals not exceeding _____ feet. 3. Type MI cable shall be supported at intervals not exceeding _____ feet. a. 2 b. 4 c. 6 d. 10 Copyright 2008 Ted "Smitty" Smith

4. Then internal depth of an outlet box used only to splice conductors to a luminaire shall NOT be less than _____. 4. Then internal depth of an outlet box used only to splice conductors to a luminaire shall NOT be less than _____. a. ½ inch b. 15/16 inch c. ¾ inch d. 1 inch Copyright 2008 Ted "Smitty" Smith

5. Direct-buried conductors emerging from grades or covers up to at LEAST _____ above finished grade. 5. Direct-buried conductors emerging from grades or covers up to at LEAST _____ above finished grade. a. 8 feet b. 10 feet c. 12 feet d. 15 feet Copyright 2008 Ted "Smitty" Smith

6. What is the MINIMUM size equipment grounding conductor required by the NEC® for a branch-circuit protected by a 50-ampere rated circuit breaker? 6. What is the MINIMUM size equipment grounding conductor required by the NEC® for a branch-circuit protected by a 50-ampere rated circuit breaker? a. 12 AWG b. 10 AWG c. 8 AWG d. 6 AWG d. 6 AWG Copyright 2008 Ted "Smitty" Smith

7. Disregarding exceptions, all three-phase, 277/480 volt, wye-connected electrical services require ground-fault protection for each service disconnecting means when rated at LEAST _____ or more. 7. Disregarding exceptions, all three-phase, 277/480 volt, wye-connected electrical services require ground-fault protection for each service disconnecting means when rated at LEAST _____ or more. a. 400 amperes b. 600 amperes c. 1000 amperes d. 1500 amperes Copyright 2008 Ted "Smitty" Smith

8. Determine the conductor ampacity given the following related information: 8. Determine the conductor ampacity given the following related information: Conductors are size 500 kcmil copper Conductors are size 500 kcmil copper Conductor insulation is THWN Conductor insulation is THWN Eight current-carrying conductors are in the raceway Eight current-carrying conductors are in the raceway Ambient temperature is 125° Ambient temperature is 125° Conduit length is 75 feet Conduit length is 75 feet Installation is a wet location Installation is a wet location a. 178.2 amperes b. 199.5 amperes c. 294.6 amperes d. 380.0 amperes Copyright 2008 Ted "Smitty" Smith

8. aTbl. 310.16 8. aTbl. 310.16 TBL. 310.15(B)(2)(a) TBL. 310.15(B)(2)(a) #500 KCMIL THWN copper ampacity before de-rating = 380 amperes #500 KCMIL THWN copper ampacity before de-rating = 380 amperes 380 amperes X.67(temp. corr.) X.7(adj. factor) = 178.22 amperes 380 amperes X.67(temp. corr.) X.7(adj. factor) = 178.22 amperes Copyright 2008 Ted "Smitty" Smith

9. Flexible metal conduit (FMC) is permitted for use in wet locations ____. 9. Flexible metal conduit (FMC) is permitted for use in wet locations ____. a. When the conductors in the FMC have a temperature rating of 90° b. When the conductors contained within the FMC are approved for use in a wet location c. If the length of the FMC is not more than 6 feet d. Never Copyright 2008 Ted "Smitty" Smith

10. Given: a trade size ½-inch rigid metal conduit (RMC) is to be installed in a Class I location and a trade size ½ conduit seal is required. The MINIMUM thickness of the sealing compound shall NOT be less than _____. 10. Given: a trade size ½-inch rigid metal conduit (RMC) is to be installed in a Class I location and a trade size ½ conduit seal is required. The MINIMUM thickness of the sealing compound shall NOT be less than _____. a. 3/8 inch b. ½ inch c. 5/8 inch d. ¾ inch Copyright 2008 Ted "Smitty" Smith

11. Where a water pipe passes over an indoor motor control center, leak protection apparatus shall have a MINIMUM clearance of ____. 11. Where a water pipe passes over an indoor motor control center, leak protection apparatus shall have a MINIMUM clearance of ____. a. 6 feet to the protection apparatus b. 6 feet to the water pipe c. 6 ½ feet to the protection apparatus d. 6 ½ feet to the water pipe Copyright 2008 Ted "Smitty" Smith

12. Branch circuit grounded conductors that are not connected to an overcurrent device shall be permitted to be sized at LEAST _____ of the continuous and non-continuous load to be served. 12. Branch circuit grounded conductors that are not connected to an overcurrent device shall be permitted to be sized at LEAST _____ of the continuous and non-continuous load to be served. a. 100 percent b. 80 percent c. 75 percent d. 125 percent Copyright 2008 Ted "Smitty" Smith

13. The MAXIMUM standard rating of the initial non-time-delay fuse for the branch- circuit, short-circuit, and ground-fault protection of a 1 HP, three-phase, 208-volt, squirrel-cage AC motor shall be ______. 13. The MAXIMUM standard rating of the initial non-time-delay fuse for the branch- circuit, short-circuit, and ground-fault protection of a 1 HP, three-phase, 208-volt, squirrel-cage AC motor shall be ______. a. 6 amperes b. 10 amperes c. 15 amperes d. 20 amperes Copyright 2008 Ted "Smitty" Smith

13. cTbl. 430.250 13. cTbl. 430.250 Tbl. 430.52 Tbl. 430.52 430.52(C)(1), Ex. 1 430.52(C)(1), Ex. 1 FLC of motor – 406 amperes X 300% = 13.8 amperes FLC of motor – 406 amperes X 300% = 13.8 amperes *NOTE: The next standard size fuse with a rating of 15 amperes should be selected. *NOTE: The next standard size fuse with a rating of 15 amperes should be selected. Copyright 2008 Ted "Smitty" Smith

14. For Class III equipment that is not subject to overloading the MAXIMUM surface temperature under operating conditions shall NOT exceed _____. 14. For Class III equipment that is not subject to overloading the MAXIMUM surface temperature under operating conditions shall NOT exceed _____. a. 120°C b. 165°C c. 248°F d. 210°C Copyright 2008 Ted "Smitty" Smith

15. When a metal wire-way contains splices and taps, the conductors, splices and taps shall not fill the wire-way to more than _____ of its area at that point. 15. When a metal wire-way contains splices and taps, the conductors, splices and taps shall not fill the wire-way to more than _____ of its area at that point. a. 20 percent b. 30 percent c. 40 percent d. 75 percent Copyright 2008 Ted "Smitty" Smith

16. In an underground installed Schedule 40 PVC conduit system that consists of 50 feet in length between pulling points, what is the MAXIMUM number of bends this conduit run may have? 16. In an underground installed Schedule 40 PVC conduit system that consists of 50 feet in length between pulling points, what is the MAXIMUM number of bends this conduit run may have? a. Four 90° bends b. Six 90° bends c. Four 120° bends d. Two 90° bends Copyright 2008 Ted "Smitty" Smith

17. Grounding electrodes made of pipe or conduit shall not be smaller than _____ electrical trade size. 17. Grounding electrodes made of pipe or conduit shall not be smaller than _____ electrical trade size. a. ½ inch b. ¾ inch c. 1 inch d. 1 ½ inch Copyright 2008 Ted "Smitty" Smith

18. Liquid-tight flexible metallic conduit (LFMC) shall NOT be used _____. 18. Liquid-tight flexible metallic conduit (LFMC) shall NOT be used _____. a. In lengths in excess of 6 feet b. In concealed work c. In hazardous locations d. Where subject to physical damage Copyright 2008 Ted "Smitty" Smith

19. Determine the allowable ampacity of a size 3 AWG THHN copper conductor given the following: 19. Determine the allowable ampacity of a size 3 AWG THHN copper conductor given the following: Two current-carrying conductors are in the conduit. Two current-carrying conductors are in the conduit. The ambient temperature is 34°C. The ambient temperature is 34°C. The terminations are rated 60°C. The terminations are rated 60°C. a. 105.6 amperes b. 85 amperes c. 81.6 amperes d. 110 amperes Copyright 2008 Ted "Smitty" Smith

19. b110.14(C) 19. b110.14(C) 310.15(A)(2) 310.15(A)(2) Tbl. 310.16 Tbl. 310.16 3 AWG THHN ampacity before de-rating = 110 amperes (90°C Col.) 3 AWG THHN ampacity before de-rating = 110 amperes (90°C Col.) 110 amperes X.96(temp. correction) = 105.6 amperes 110 amperes X.96(temp. correction) = 105.6 amperes Size 3 AWG (60°C col.) = 85 amperes should be selected. Size 3 AWG (60°C col.) = 85 amperes should be selected. Copyright 2008 Ted "Smitty" Smith

20. When an overcurrent protective device for a surge-protective device is located at the service location it _____. 20. When an overcurrent protective device for a surge-protective device is located at the service location it _____. a. Is not to be counted a service disconnect. b. Shall be considered as a service disconnecting means c. Shall be more than 10 feet from the main disconnecting means d. Shall be prohibited Copyright 2008 Ted "Smitty" Smith

End of Drill Click the left mouse button to advance back to the first question. Each question will now be repeated without the timer to give you a chance to review it and find the answer. Click the left mouse button to advance back to the first question. Each question will now be repeated without the timer to give you a chance to review it and find the answer. Clicking the left mouse button will advance the slide to the answer and the code reference. Clicking the left mouse button will advance the slide to the answer and the code reference. Copyright 2008 Ted "Smitty" Smith