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9. When a central air-conditioning unit label states "Maximum size time-delay fuse 50 amperes," what type of circuit breaker is permitted to provide running overload protection? Select one: a. 50-ampere circuit breaker b. 50-ampere HACR circuit breaker c. 65-ampere circuit breaker d. circuit breakers are not permitted for this application

????

46. Where it appears on an air-conditioner nameplate, ___ is used to determine the largest size OCPD that can used to protect the AC unit. Select one: a. MCA b. volts c. MOCP d. ph e. none of these

???? not b

2. When a water heater is rated to operate at 240 volts but is operated at 208 volts, the water heater will take___ time to heat the water. Select one: a. more b. the same c. less

a

22. When a rooftop air conditioner is installed on a "strip" shopping center, a 15- or 20-ampere 125-voltreceptacle is required to be installed for servicing the equipment. This receptacle is permitted to be connected to the circuit on the ___ side of the equipment disconnecting means. Select one: a. line b. load c. either a or b d. neither a nor b

a

24. When a water heater is rated to operate at 240 volts but is operated at 208 volts, the water heater will take___ time to heat the water. Select one: a. more b. the same c. less

a

25. Scenario 125.103.240 A duct heater contains two heating elements. Each element is rated to deliver 14.5 KW at 240 volts. The nameplate on the duct heater indicates that it can be connected to either a 240- or 480-volt circuit. In this case, the supply circuit is 240 volts. For Scenario 125.103.240, the duct heater will deliver ___ kW of power. Select one: a. 29 b. 33.1 c. 30.2 d. 7.25 e. 14.5

a

26. Scenario 125.103.480 A duct heater contains two heating elements. Each element is rated to deliver 14.5 KW at 240 volts. The nameplate on the duct heater indicates that it can be connected to either a 240- or 480-volt circuit. In this case, the supply circuit is 480 volts. For Scenario 125.103.480, the duct heater will deliver ___ kW of power. Select one: a. 29 b. 33.1 c. 30.2 d. 7.25 e. 14.5

a

3. Supply conductors for electric baseboard heaters generally have to be rated ___. Select one: a. 90°C b. 60°C c. 75°C d. not rated

a

32. Section ___ of the NEC states that a central heating system must be supplied by an individual branch circuit. Select one: a. 422.12 b. 218.9 c. 210.9 d. 350.8(A)

a

35. Without remarking, the white conductor contained in a 12/2 with ground AC cable can be used for 24-voltmotor control system wiring. Select one: a. True b. False

a

28. A line-voltage thermostat is used to control a household heating apparatus that is rated at 240 volts. The thermostat disconnects ___. Select one: a. all circuit conductors b. both ungrounded conductors c. the grounded conductor only d. the grounding conductor only

b

29. What standard size fuses would be required for a 240-volt, 15,000-watt furnace? (Assume single-phase.) Select one: a. 65 amperes b. 80 amperes c. 100 amperes d. 90 amperes

b

37. Where contained in a cable, the Code reference that states when a conductor with white insulation may be used as an ungrounded circuit conductor is in Section ___. Select one: a. 200.6(E) b. 200.7(C) c. 200.9 d. none of these

b

39. Class 2 control circuit wiring ___ required to be installed in a raceway or cable. Select one: a. is b. is not

b

40. When Class 2 control circuit wiring enters the wiring enclosure of a piece of equipment, this wiring is permitted to pass through the line voltage section of the enclosure if no splices are made in the Class 2wiring. Select one: a. True b. False

b

45. Scenario 125.102.240 The nameplate on a 1Ø boiler (big water heater) indicates that it can be connected to either a 240- or 480-voltcircuit. In this case, the supply circuit is 240 volts. It contains two heating elements. Each element has a rating of 11.3 KW at 240 volts. For Scenario 125.102.240, ___ volts are applied to each element . Select one: a. 120 b. 240 c. 60 d. 480

b

5. Evaporator coils are used in ___ systems. Select one: a. gas-fired b. air-conditioning c. water-heating d. all of these

b

6. A gas-fired furnace with a blower motor ___ permitted to utilize a cord-and-plug connection as the disconnecting means. Select one: a. is b. is not

b

41. Scenario 125.101.240 The nameplate on a 1Ø boiler indicates that it can be connected to either a 240- or 480-volt circuit. In this case, the supply circuit is 240 volts. It contains two heating elements. Each element has a rating of 16.2 kW at240 volts. A boiler is simply a large water heater. For Scenario 125.101.240, the boiler will supply ___ watts of power. Select one: a. 8,100 b. 16,200 c. 64,800 d. 32,400

d

43. Scenario 125.101.480 The nameplate on a 1Ø boiler indicates that it can be connected to either a 240- or 480-volt circuit. In this case, the supply circuit is 480 volts. It contains two heating elements. Each element has a rating of 16.2 kW at240 volts. A boiler is simply a large water heater. For Scenario 125.101.480, ___ volts are applied to each element. Select one: a. 60 b. 480 c. 120 d. 240

d

8. HACR is an abbreviation for ___. Select one: a. High Ampere Current Rating b. Heavy Air Conditioning Requirement c. High Air Circulation Recovery d. Heating Air Conditioning Refrigeration

d

30. When air-conditioning equipment is installed in an attic, a ___ is required. Select one: a. disconnecting means for the AC equipment b. lighting outlet near the AC equipment c. light switch near the attic entrance d. convenience receptacle within 25 feet of the AC equipment e. all of these

e

21. When a rooftop air conditioner is installed on a "strip" shopping center, a 15- or 20-ampere, 125-voltreceptacle is required to be installed for servicing the equipment. Additionally, if installed outside, the receptacle is required to ___. I. be located 25 feet or less from the equipment II. be AFCI protected Select one: a. I only b. II only c. both I & II d. neither I nor II

a

38. In a dwelling, 12-volt thermostat wiring is generally considered to be ___ wiring. Select one: a. Class 2 b. Class 3 c. Class 1

a

4. The white conductor contained in a 12/2 with ground MC cable can be marked with red tape where visible or accessible and used to connect a 240-V pump motor. Select one: a. True b. False

a

42. Scenario 125.101.480 The nameplate on a 1Ø boiler indicates that it can be connected to either a 240- or 480-volt circuit. In this case, the supply circuit is 480 volts. It contains two heating elements. Each element has a rating of 16.2 kW at240 volts. A boiler is simply a large water heater. For Scenario 125.101.480, the elements will be connected in ___. Select one: a. series b. parallel

a

44. Scenario 125.102.240 The nameplate on a 1Ø boiler (big water heater) indicates that it can be connected to either a 240- or 480-voltcircuit. In this case, the supply circuit is 240 volts. It contains two heating elements. Each element has a rating of 11.3 KW at 240 volts. For Scenario 125.102.240, the elements in will be connected in ___. Select one: a. parallel b. series

a

7. Because of the low voltage involved, voltage drop ___ a consideration when running thermostat wiring. Select one: a. is b. is not

a

23. When a rooftop air conditioner is installed on a "strip" shopping center, a 15- or 20-ampere, 125-voltreceptacle is required to be installed for servicing the equipment. Additionally, if installed inside the equipment enclosure (dry location), the receptacle is required to __________. I. have a weatherproof cover II. be GFCI protected Select one: a. I only b. II only c. both I & II d. neither I nor II

b

27. Scenario 125.104.120 A pasta cooker contains two heating elements. Each element is rated to deliver 5.8 KW at 120 volts. The nameplate on the pasta cooker indicates that it can be connected to either a 120- or 240-volt circuit. In this case, the supply circuit is 120 volts. For Scenario 125.104.120, ___ amps of current will flow through each branch circuit conductor. Select one: a. 24.17 b. 96.67 c. 41.38 d. 48.33 e. 20.69

b

20. An air conditioner will be installed on the roof of a "strip" shopping center. The NEC requires that a 15- or20-ampere, 125-volt receptacle be installed for servicing the equipment. The receptacle will be outside and exposed to the weather. The receptacle is ___. I. required to have a weatherproof cover installed II. permitted to be connected to the circuit on the line side of the equipment disconnecting means Select one: a. I only b. II only c. both I & II d. neither I nor II

c

31. When a circuit for a cord-connected window (room) air conditioner is installed, the requirements for connection to an equipment grounding conductor are located in Section ___ in the NEC . Select one: a. 250.110 b. 250.112 c. 250.114 d. none of these

c

34. A window (room) air conditioner is cord connected and a dedicated branch circuit will be run for the receptacle. The air conditioner will draw 19 amps. The smallest circuit breaker that can be installed for the circuit is ___ amps. Select one: a. 30 b. 15 c. 25 d. 20 e. none of these

c

47. A central air-conditioning unit is to be installed and you are required to run power to it. The nameplate information is: 1 ph 240 volts MCA 32.7 MOCP 50-A fuse You are permitted to install which of the following where the panel is within sight of the AC unit? Select one: a. a 60-A breaker in the panel b. a 50-A breaker in the panel c. a 60-A breaker in the panel with 50-A fuses in an AC disconnect switch d. none of these

c

48. A new central air-conditioning unit is to be installed. This new AC replaces an old one. The nameplate information on the new equipment is: 1Ø 240 volts MCA 22.3 MOCP 35 A The existing circuit has 8 AWG Romex connected to a 50-A breaker in the panel and a fused safety switch near the unit. There are 50-amp fuses in the safety switch. Which of the following actions by the electrician will be acceptable? I. replace the fuses with ones rated at 35 amps II. replace the breaker with a 2-pole 35 amp Select one: a. I only b. II only c. either I or II d. neither I nor II

c

1. Which of the following are used to provide electric heating? Select one: a. radiant heating panels b. heat pumps c. boilers d. all of these

d

33. On circuits supplying cord-and-plug-connected air conditioners, the branch-circuit overcurrent protective device rating is not permitted to exceed ___. Select one: a. the ampacity of the branch-circuit conductors b. the rating of the receptacle to which the air conditioner is connected c. 50 percent of the total load of the air conditioner plus other loads on the same circuit d. either a or b, whichever is less

d

36. A conductor with white insulation may be used as an ungrounded circuit conductor ___. The conductor is contained in a cable. Select one: a. if used for 12-volt door chime system wiring b. if marked with black tape where visible or accessible and used to connect a 240-V pump motor c. if marked with red tape where visible or accessible and used for a traveler from a 3-way switch d. if marked with blue tape where visible or accessible and used to feed the "hot" to a switch e. all of the above

e

49. You are sent on a service call to install power for a new central air-conditioning unit. The nameplate has the following information: ph 1 volts 240 MCA 25.5 MOCP 45 A The old (inefficient) unit has 6 AWG copper branch circuit conductors, a 60-A breaker in the panel, and 60-amp fuses in the AC disconnect switch next to the unit. You are permitted to ___. Select one: a. replace the 60-A breaker in the panel with a 45 A & leave the 60-A fuses b. replace the 60-A breaker in the panel with a 50 A & change the disconnect fuses to 50 A c. leave the 60-A breaker in the panel but change the fuses in the disconnect to 50 amps d. leave the 60-A breaker and the 60-amp fuses e. none of these

e


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