Circuits.

Question 1

2. Min size for branch circuit wire?

Answer 1

14 AWG.

Question 2

3. How many sq. ft. min for 1 general purpose circuit ?

Answer 2

500 sq. ft.

Question 3

4. Max distance along wall to receptacle?

Answer 3

6 feet.

Question 4

5. Min wall length for receptacle?

Answer 4

> =2 feet.

Question 5

6. Min hallways length for receptacle?

Answer 5

10 feet.

Question 6

7. Circuit for bathroom?

Answer 6

Separate 20A ckt for bath receptacles or dedicated 20A ckt to each bathroom.

Question 7

8. Laundry circuit?

Answer 7

Min 1 20 A circuit to receptacle.

Question 8

1. How must the black and red wires originate in a 3-conductor Romex cable?

Answer 8

From different poles or the neutral can be overloaded because it carries the sum of the currents.

Question 9

9. How is common3-wire circuit run to a duplex receptacle for the dishwasher and the garbage disposer?

Answer 9

By breaking the connecting tab on a duplex receptacle each half can be fed by separate circuits with 240 V potential between the circuits. Each half can be fed by separate circuits with a shared neutral.

Question 10

10. Receptacle rules for kitchen countertops?

Answer 10

1. All individual counter spaces >= 12 in. require receptacle.
2. Spacing so no point >= 24 in. from receptacles.
3. Max 20 in. above countertop.
4. Island and peninsula counter spaces min 1 receptacle.

Question 11

11. What must be also considered in determining the ampacity of a wire?

Answer 11

The ambient temperature.

Question 12

12. How shall You size Motor circuit?

Answer 12

1. Use name plate FLA only for overload protection size.
2. Find FLC from hp and voltage in table.
3. Size circuit conductor to 125% of FLC (full-load-current).
4. Size breaker 259% FLC.
5. Size TD (time delay) fuse 175% FLC.

Question 13

13. Protection NM cable?

Answer 13

1/16” steel plate, if closer than 1-1/4” to framing surfaces.

Question 14

14. How is AC cable (BX) grounded?

Answer 14

Armor is EGC - don’t bring bond wire into box.

Question 15

15. How is MC cable grounded?

Answer 15

By green wire. Metal armor is not a ground.

Question 16

16. Max voltage drop?

Answer 16

1. 3% on a branch circuit.

2. 5% overall voltage drop including the feeders.

Question 17

17. How can You overcome a voltage drop problem?

Answer 17

1. Use larger wire than the minimum size and make sure that all connections are tight.
2. Use fewer than the maximum number of outlets on each circuit.

Question 18

18. What is used to maintain clearance from cable to stud or joint edge?

Answer 18

Stand-off clamp.

Question 19

19. How can You protect cable within 6 feet of scuttle?

Answer 19

Boards protect cables.

Question 20

20. How can You protect Romex cable under the floor?

Answer 20

1. > = 3/8 Romex clamp to joists.

2.

Question 21

21. Max bends between raceway pull points?

Answer 21

360* max.

Question 22

22. What raceway can be bury in soil?

Answer 22

RMC (Rigid metal conduit).

EMT (Electrical metallic tubing) not OK.

Question 23

23. 2 way to run 3 way switch circuit?

Answer 23

1. 2 wire g Romex supply 120 V to 3 way switch, 3 wire g Romex run to another 3 way switch, 2 wire g Romex run to fixture box. All neutral interconnected.
2. 2 wire g Romex bring 20 V to fixture box, 2 wire g Romex run to 3 way switch, white is connected to hot and black to neutral, 3 wire g Romex run to other 3 way switch. White is reidentifyed in each box.