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Discussion Starter · #1 ·
I have a practice test with no answer key. Can you guys help me out?
1. The amount of fault current at the service depends upon what?

2.the maximum overcurrent protection for the primary of. 240v transformer with a primary current of 40 Amps is how many amps?

3. A dry type transformer may be located in a suspended ceiling space where it is not readily accessible if the voltage is 600 volts or less and has a maximum rating of how many kva?

4. Where overhead service drop conductors of a 120/240 volt service pass over a roof that has a slope of 6:12 and the roof is not an overhanging roof the minimum clearance from the roof to the overhead conductors is how many feet?

5. Where the footing steel serves as the only grounding electrode for a building does the code require a maximum resistance in ohms for this concrete encased electrode? If so how many ohms?

6.for a residential service calculation heat pump loads are required to be calculated at what percent of be nameplate rating when used without any supplemental electric heating?

7. When a combination of transformers and utilization equipment are supplied by a feeder over 600 volts the conductor ampacity shall not be less than the sum of the name plate ratings of the transformers and the equipment that will be operated simultaneously at what percent?

8. Size 14 branch tap conductors are allowed to be tapped from a 20a circuit under what conditions if any at all?

9. The maximum total rating of fastened in place utilization equipment permitted on a 20 a branch circuit that also serves lighting is how many amps?

10. The ECG required on an air conditioning compressor fed with a 6 awg cu conductor and a 60 amp breaker is what?

11. The purpose of using an insulated grounding conductor connected to an isolated grounding receptacle is?

12. The maximum overcurrent device permitted to protect circuit conductors having an ampacity of 55 from an overload short is how many amp?

13. Where flexible cord is attached to the building ceiling with a suitable tension take up device the maximum length of cord between device and supply point is how many feet?

14. Minimum cover requirements for underground RMC with under 600v located in a commercial parking lot shall
Be how many inches?

15. This one I just need to know where the table is to convert awg to cross sectional area in inches

16. Nm cable must be secured within how many inches of a single gang box with no internal clamps?

17. What is the minimum wiring space in inches required between the bottom of a switchboard and non insulated bus bars?

18. Are class 2 remote control cables permitted to be strapped or otherwise attached to raceways as support? If so under what conditions?

19. 3/8inch fmc may be used as unsupported tap connections to light fixtures provided the length does not exceed how many feet?

20. For a hermetic refrigerant motor compressor with a rated load current of 20 amps where the branch circuit protection is sufficient for the starting current the maximum permitted rating for the branch circuit protective device is how many amps?

21. Equipment shall be installed and used in accordance with instructions included on the manufacturers suggested instructions? True or false

22. The rated load current for an air conditioner compressor is 30 amps. A 50 amp breaker will not hold the starting current. The maximum size breaker permitted for branch circuit protection is how
Many amps?

23. A motor controller is tapped from the load side of the motor short circuit protective device. The control circuit conductors are 14 awg thwn copper. The conductors require only short circuit protection and do
Not extend beyond the motor control equipment enclosure. What is the maximum over current protection permitted for this
Motor control circuit?

24. Branch circuit conductors that serve a 3 phase 230 volt 15 hp induction type motor shall have an allowable ampacity of atleast how many amps?

25. A wound motor no code letter 2 hp single phase 115 v motor has branch circuit conductors that are protected by a non time delay fuse.
What is the maximum rating for the branch circuit short circuit?

26. When the design and operation of the generator will prevent overloading the conductors shall be not less than?

27. What is the maximum operational setting of an adjustable inverse time breaker protecting a 10 hp 208 volt 3 phase squirrel cage motor branch circuit?

28. The inverse time circuit breaker shall be rated at a maximum of what percent of the rated load?

29. The maximum overload protection device rating responsive to motor current permitted by the nec for a 25 hp 208 volt 3 phase induction type motor marked with a temperature rise of 50 degrees C is how many amps?

30. For a branch circuit that serves a short time duty 15 minute rated motor that has a nameplate current rating of 25 amps the thwn conductors shall be atleast what size awg? All terminal connections are rated 75 degrees C

31. 3 motors with full load amp ratings of 10 20 and 30 are fed by one feeder. The motor feeder conductors must have an ampacity of at least how many amps?

32. Branch circuit ECGs serving receptacles for sensitive electronic equipment shall be grounded. The ECG shal be run to the bus marked what?

33. Instrumentation tray cable with 22 awg conductors is permitted to be used for circuits operating at a max of how many amps?

34. Minimum clearance above swimming pools for 120 volt conductor supported by grounde messenger wire?

Thank you in advance to anyone who can help!
 

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Why don't you tell us what you already know so we can help you out.

Giving you all the answers won't do you any good.
 

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I agree-- put your answer down and we will let you know. That is alot of work for us to do so maybe members can pick and choose the ones they want to do.
 

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I got you started on the first few with article numbers

I have a practice test with no answer key. Can you guys help me out?
1. The amount of fault current at the service depends upon what? Not sure you will find this in the NEC

2.the maximum overcurrent protection for the primary of. 240v transformer with a primary current of 40 Amps is how many amps? T. 450.3(B)

3. A dry type transformer may be located in a suspended ceiling space where it is not readily accessible if the voltage is 600 volts or less and has a maximum rating of how many kva? Art. 450.13

4. Where overhead service drop conductors of a 120/240 volt service pass over a roof that has a slope of 6:12 and the roof is not an overhanging roof the minimum clearance from the roof to the overhead conductors is how many feet? Art. 230.24

5. Where the footing steel serves as the only grounding electrode for a building does the code require a maximum resistance in ohms for this concrete encased electrode? If so how many ohms? Art. 250.52

6.for a residential service calculation heat pump loads are required to be calculated at what percent of be nameplate rating when used without any supplemental electric heating? art. 220. 82

7. When a combination of transformers and utilization equipment are supplied by a feeder over 600 volts the conductor ampacity shall not be less than the sum of the name plate ratings of the transformers and the equipment that will be operated simultaneously at what percent?

8. Size 14 branch tap conductors are allowed to be tapped from a 20a circuit under what conditions if any at all?

9. The maximum total rating of fastened in place utilization equipment permitted on a 20 a branch circuit that also serves lighting is how many amps?

10. The ECG required on an air conditioning compressor fed with a 6 awg cu conductor and a 60 amp breaker is what?

11. The purpose of using an insulated grounding conductor connected to an isolated grounding receptacle is?

12. The maximum overcurrent device permitted to protect circuit conductors having an ampacity of 55 from an overload short is how many amp?

13. Where flexible cord is attached to the building ceiling with a suitable tension take up device the maximum length of cord between device and supply point is how many feet?

14. Minimum cover requirements for underground RMC with under 600v located in a commercial parking lot shall
Be how many inches?

15. This one I just need to know where the table is to convert awg to cross sectional area in inches

16. Nm cable must be secured within how many inches of a single gang box with no internal clamps?

17. What is the minimum wiring space in inches required between the bottom of a switchboard and non insulated bus bars?

18. Are class 2 remote control cables permitted to be strapped or otherwise attached to raceways as support? If so under what conditions?

19. 3/8inch fmc may be used as unsupported tap connections to light fixtures provided the length does not exceed how many feet?

20. For a hermetic refrigerant motor compressor with a rated load current of 20 amps where the branch circuit protection is sufficient for the starting current the maximum permitted rating for the branch circuit protective device is how many amps?

21. Equipment shall be installed and used in accordance with instructions included on the manufacturers suggested instructions? True or false

22. The rated load current for an air conditioner compressor is 30 amps. A 50 amp breaker will not hold the starting current. The maximum size breaker permitted for branch circuit protection is how
Many amps?

23. A motor controller is tapped from the load side of the motor short circuit protective device. The control circuit conductors are 14 awg thwn copper. The conductors require only short circuit protection and do
Not extend beyond the motor control equipment enclosure. What is the maximum over current protection permitted for this
Motor control circuit?

24. Branch circuit conductors that serve a 3 phase 230 volt 15 hp induction type motor shall have an allowable ampacity of atleast how many amps?

25. A wound motor no code letter 2 hp single phase 115 v motor has branch circuit conductors that are protected by a non time delay fuse.
What is the maximum rating for the branch circuit short circuit?

26. When the design and operation of the generator will prevent overloading the conductors shall be not less than?

27. What is the maximum operational setting of an adjustable inverse time breaker protecting a 10 hp 208 volt 3 phase squirrel cage motor branch circuit?

28. The inverse time circuit breaker shall be rated at a maximum of what percent of the rated load?

29. The maximum overload protection device rating responsive to motor current permitted by the nec for a 25 hp 208 volt 3 phase induction type motor marked with a temperature rise of 50 degrees C is how many amps?

30. For a branch circuit that serves a short time duty 15 minute rated motor that has a nameplate current rating of 25 amps the thwn conductors shall be atleast what size awg? All terminal connections are rated 75 degrees C

31. 3 motors with full load amp ratings of 10 20 and 30 are fed by one feeder. The motor feeder conductors must have an ampacity of at least how many amps?

32. Branch circuit ECGs serving receptacles for sensitive electronic equipment shall be grounded. The ECG shal be run to the bus marked what?

33. Instrumentation tray cable with 22 awg conductors is permitted to be used for circuits operating at a max of how many amps?

34. Minimum clearance above swimming pools for 120 volt conductor supported by grounde messenger wire?

Thank you in advance to anyone who can help!
 

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The following sections apply to some of the questions. Often the sections have multiple subdivisions and some of the answers are found in an exception. Some of the sections require very close reading to get the correct answer.

110.3, 210.19, 210.23, 240.4, 250.146, 300.5, 300.11, 348.30, , 430.22, 430.24, 430.52, 430.72, 440.22, and 445.13.
 

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1- impedance of transformer feeding it. Then it's a huge long engineering formula that no normal electrician can just ring off from their hip...phew.
 

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Discussion Starter · #8 ·
Wow I didn't realize how ridiculous that lost of questions is until I looked at it again. My
Biggest problem is understanding the inverse time breaker with motors.
 

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Discussion Starter · #10 ·
Thanks for the article references. I'm getting somewhere. Just hard to understand some
Of these things purely in theory. I mean that in I have no
Experience with large motors
 

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Discussion Starter · #12 ·
Ok this is what I've got so far:
1.?
2. 50 a
3. 50 kva
4. 3 feet
5. No
6. 100%
7. 125%
8. Not allowed
9. 4?
10. 10 awg copper
11. Harmonic interference
12. 60
13. 6 feet
14. 24 inches
15.
16. 8 inches
17. 6 inches
 
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