ELECTRICAL

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23. What size wire is found on most general purpose outlets for lights and receptacles?

14 gauge

10. 3 common areas of water penetration:

1. Conduit joints; Mast head 2. Roof flashing; Meter base; 3. House entry

17. There can be up to 10 throws to disconnect all of the electricity in the house:

False A maximum number of breaker throws is -----

24. How is a type S fuse different than a conventional fuse:

S-type fuses have a special base that screws permanently into fuse panel and permits only the right size fuse to fit. NOTE: A P-fuse is heat sensitive.

48. Describe how you would test a GFI receptacle during an inspection:

Use a conventional circuit tester and operate the test button on the receptacle.

33. What are the issues about running through steel studs?

Wire may be damaged by sharp edges of steel studs. Wires passing through holes should be protected with grommets for example. Wires running parallel to studs should stand off the studs.

16. The size of the fuse should be:

the same as the rating of the wire

42. What caused the problems?

- Aluminum wire - Tends to creep out from under terminal screws; - Forms rust (oxide) that is an electrical insulator; - Is softer than copper and easier to damage when working with the wire - Was, in some of the early material, a low quality wire prone to weakness and breaking.

34. Examples of poor locations for wiring:

- Exposed to damage on wall surfaces, for example Under carpets - Close to the edge of studs or joists - In ductwork - Against pipes, ducts, exhaust flues vents, chimney's or other heat sources

5. Eight common problems with service drops:

- Overhead wires too low - Overhead wires too high - Damaged or frayed wires - Trees or vines interfering with wires - Wires too close to doors or windows - Wires not well secured to the house - Poor connection between service drop and service entrance - Inadequate clearance from roofs

20. Why would we not run the service entrance conductors throughout the entire house to feed electrical needs in every room:

- Too expensive - Too difficult to wire - Lack of localized control

13. The main fuses or breakers are most likely to trip:

- during cold weather; - during hot weather - after 11:00 p.m. - when many large appliances are on - when most of the lights are on

12. Implications of an undersized service include:

- shock hazard - fire hazard - shock and fire hazard - melting insulation - nuisance tripping of the main fuses or breakers

39. Four common conditions with knob-and-tube wiring:

1. Connections not in boxes 2. Brittle wire, insulation or sheathing 3. Wire buried in insulation 4. Fused neutral

40. Three common conditions found with aluminum wiring:

1. Connectors not compatible with aluminum 2. No anti-oxidant grease on stranded wires 3. Overheating

27. 4 different branch wire materials you might see:

1. Copper 2. Aluminum 3. Copper clad aluminum 4. Tin/solder-dipped copper

35. Seventeen common branch circuit wire conditions.

1. Damaged 2. Not well secured 3. Loose connections 4. Open splices 5. Wires to close to ducts, pipes, vents, chimney's, and flues 6. Wires too close to the edge of studs or joists 7. Wires run through steel studs without protection 8. Exposed wires on walls or ceilings 9. Exposed wires in attics 10. Wire run under carpets 11. Cable used outdoors 12. Buried cable not rated for buried use 13. Overhead wires not stranded 14. Household wire used as extension cords 15. Undersized wire 16. Improper color coding 17. Abandoned wire

44. Twelve common lighting problems found in houses

1. Damaged or loose 2. Overheating 3. Inoperative 4. Obsolete. 5. Not grounded. 6. Missing 7. Poor stairway lighting 8. Conventional lights used in wet areas 9. Improper pot light used in installations 10. Improper closet lighting 11. Heat lamps over doors 12. Isolating links needed on pull chains

43. Nine examples of outdoor wiring problems commonly associated with homes:

1. Indoor-type wire used outdoors 2. Garage door opener powered with extension cord 3. Wires within 5 to 7 ft of grade level or garage floor level 4. Wires are not well secured to walls. 5. Wires run across roof surfaces. 6. Wires run through gutters or downspouts. 7. Overhead wires to out-buildings are solid rather than stranded conductors. 8. Extension cords are used as permanent exterior wires. 9. Buried wires not suitable for use underground.

28. 3 different cable types you might see:

1. NMD; 2. NMW 3. BX (АC-90)

9. 10 common problems with service entrance conductors:

1. No drip loop 2. No mast head 3. Mast head not weather-tight 4. Service entrance wires too close to the roof 5. Mast or conduit bent 6. Mast or conduit rusted 7. Mast rotted (if wood) 8. Mast conduit or cable not well secure 9. Mast conduit or cable not weather-tight 10. Conduit or cable not well sealed at house/wall penetration; Cable frayed, damaged or covered by siding

26. 14 conditions found in panels of all types:

1. Obsolete and/or fused neutrals 2. Damaged panel or components 3. Loose panel 4. Inappropriate support material 5. Loose or missing door 6. Openings in panel 7. Panel too small 8. Overheating 9. Rust or water in panel 10. Circuits not labeled 11. Panel crowded 12. Poor access 13. Upside down 14. Not suitable for aluminum wiring

18. 15 common conditions you might find in a service box:

1. Poor Access; Not well secured 2. Rust 3. Unprotected opening 4. Inappropriate mounting service 5. Damaged parts 6. Overheating 7. Incorrect fuse or breaker size; box rating too small 8. Service entrance wires exposed in the house 9. Poor connections 10. Illegal taps 11. Neutral wire by-passes service box 12. Fused neutral wire 13. Fuses upstream of disconnect switch 14. Obsolete service box 15. Exterior box not weather-tight

36. Three types of connectors:

1. Terminal screws 2. Push-in connectors 3. Solderless connectors

4. Five safe practices to protect you during your inspection:

1. Use a voltage detector to ensure that any electrical equipment you are about to touch is not live. 2. Wear rubber soled shoes 3. Do not stand in water when touching electrical equipment 4. Use insulated tools 5. Do not let your client stand beside a panel you are working on;

21. Which devices are considered the brains of the electrical system?

33. Fuses and circuit breakere

Motors: Horsepower (hp) = 746 watts

746 watts = 1 hp

47. Why should heat lamps not be located over doors?

A towel thrown over the door may be ignited by a heat lamp.

5. A brief definition of a volt:

A volt is the measure of the force or potential energy in an electrical system (V=IxR)

8. Give a brief definition of a watt:

A watt is a measure of the rate of electrical energy being consumed or released (P-VxI)

41. When was it used?

Aluminum wiring was used from the mid 1960's to the late 1970's. (1965-1978)

7. A brief definition of an amp:

An amp is a measure of how much electrical current is flowing (I-V/R)

6. A brief definition of an ohm:

An ohm is a measure of resistance to electrical flow in a conductor or insulator (R=V/I)

37. What is an open splice?

An open splice is a connection that is not made inside a junction box with a cover.

Power Circle: 9. Using both circles you can calculate answers asking for Voltage (E), Resistance or Ohm's ($), Current or Amperes (I), and Power or Watts (P).

Cover the missing value with your thumb and then do the calculation showing on the other 2. P = I x E I = P /E E = P / I

10. Start the exam by drawing both circles Ohm's Law: Using Ohm's Law, if you know 2 of the values you can figure out the missing value. Cover the missing value with your thumb and then do the calculation showing on the other 2.

E = I x R I = E /R R = E / I

MOTOR CALCULATIONS: 1. Motor efficiency must be considered to determine the true power single-phase

Efficiency = Power Output Power Input Horsepower = Volts x Amps x Efficiency x PF 746 Amperes = 746 x HP Volts x Efficiency x PF PF = Power Factor

30. How are extension cords different from permanent wiring:

Extension cords are flexible and stranded. They have lighter sheathing that is not intended to be stapled or secured in place permanently. The gauge of extension cords, is typically 16 or 18 gauge, smaller thán permanent wiring.

15. A 200 amp service will have 2- 100 fuses in the service panel:

False

3. The wire size for the service drop must be the same as the wire size for the service entrance conductors:

False

7. All service entrance conductors must be attached to the building above roof level:

False

8. The drip loop should be as close to the roof surface as possible:

False

32. Running along the length of the wire, how far apart should the supports be:

Four and a half

29. What is the difference between insulation and sheathing?

Insulation is wrapped around individual wires, and sheathing forms the cables by wrapping around the insulated wires

3 How much electrical current does it take to kill you?

Less than an amp.

45. How are lights tested?

Lights are tested by turning them on and off by their switches.

22. What is the advantage of a 240 volt circuit?

More electricity can flow at lower amperace ratings

46. Problems commonly associated with potlights:

Pot lights may be inappropriately installed in insulated ceilings Inappropriate bulbs may be used in the pot lights.

38. Describe how knob-and-tube wiring is visibly different from modern cable:

The black and white wires are separate so the circuit wires usually run in pairs. There are ceramic tubes protecting the wires where it passes through joists or studs. There are ceramic knobs where the wire changes direction.

40. How would you identify aluminum wiring?

The conductor itself is silver colored. The sheathing usually has the wordALUMINUM,ALUM or AL.

2. The size of the fuse should be:

The same as the rating of the wire

25. How is a type D fuse special:

This is a time delay fuse that will allow over-current to flow through it for a short period.

4. How many wires would you typically find in a 240 volt service drop?

Three

19. From the point where the ground and the neutral wires connect, there are two paths to ground. What are they:,

Through the neutral wire or through the grounding electrode condnd, water pipes or ground rods.

1. We are required to look at the service drop and service laterals:

True

11. The size of the electrical service has to be reported according to ASHI® Standards:

True

2 The service size is determined by the amperage and voltage ratings of the service:

True

31. When a wire leaves a box, how far should it run before it is supported or secured:

Twelve inches

6. Service laterals are:

Underground

14. Which of the following is a reliable way to identify the service size?

the size of the service drop wires; the distribution panel rating; the service box rating; the service entrance wires; the service entrance conduit


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