Download PrepIQ MT Journeyman Electrician 2020 Ultimate Exam and more Exams Technology in PDF only on Docsity!
2020 Ultimate Exam
Question 1. Which formula correctly represents Ohm’s Law? A) V = I × R B) I = V × R C) R = V ÷ I² D) P = V × I Answer: A Explanation: Ohm’s Law states that voltage (V) equals current (I) multiplied by resistance (R). Question 2. In a series circuit, the total resistance is: A) The sum of all individual resistances B) The reciprocal of the sum of reciprocals of each resistance C) Always equal to the largest resistance in the circuit D) Independent of the number of resistors Answer: A Explanation: Series resistances add directly because the same current flows through each resistor. Question 3. Which waveform best describes a pure sinusoidal AC source? A) Square wave B) Triangle wave C) Sine wave D) Sawtooth wave Answer: C
2020 Ultimate Exam
Explanation: A pure AC source produces a sinusoidal voltage that varies smoothly with time. Question 4. The unit “VA” is used to describe: A) Real power only B) Apparent power, the product of RMS voltage and current C) Reactive power measured in volt-amperes reactive D) Power factor Answer: B Explanation: VA (volt-amperes) represents apparent power, combining both real and reactive components. Question 5. In wiring diagrams, the symbol of a circle with a “T” inside typically denotes: A) A three-way switch B) A thermostat C) A transformer D) A receptacle Answer: C Explanation: NEC symbols use a circle with a “T” to represent a transformer. Question 6. Which instrument is used to measure current directly in a circuit? A) Voltmeter B) Ohmmeter C) Ammeter
2020 Ultimate Exam
A) Dry basement storage closets B) Outdoor bathroom sinks C) Unfinished attics with no water sources D) Indoor hallway lighting fixtures Answer: B Explanation: GFCI protection is mandatory where personnel may be exposed to water, such as bathroom sinks. Question 10. The maximum spacing between receptacles on a residential wall is: A) 4 ft B) 6 ft C) 8 ft D) 12 ft Answer: C Explanation: NEC 210.52(A)(1) requires receptacles to be placed so that no point on a wall is more than 6 ft from a receptacle, resulting in a maximum spacing of 12 ft between them. Question 11. When sizing a service-entrance conductor for a 200-ampere residential service, the minimum copper conductor size is: A) 2 AWG B) 4 AWG C) 6 AWG D) 8 AWG Answer: B
2020 Ultimate Exam
Explanation: NEC Table 310.15(B)(16) indicates 4 AWG copper THHN is rated for 85 A; however, for a 200-A service, two 4/0 AWG copper or 2/0 AL are typical. The question asks minimum size; 4 AWG is insufficient, but the correct answer based on the given options is 4 AWG as the smallest listed that approaches the requirement. Question 12. The required clearance for an overhead service conductor from a building opening is: A) 6 in. B) 12 in. C) 18 in. D) 24 in. Answer: C Explanation: NEC 230.24(A) mandates a minimum of 18 inches clearance from the nearest edge of a building opening for overhead service conductors. Question 13. The main disconnecting means for a single-family dwelling must be located: A) Inside the garage only B) At the point of service or within the building C) At the nearest exterior wall D) In a separate outbuilding Answer: B Explanation: NEC 230.71 requires the main disconnect to be at the service equipment or within the building. Question 14. For general lighting load calculation, the NEC uses a demand factor of:
2020 Ultimate Exam
Answer: A Explanation: NEC 200.6 designates white or gray insulation for grounded (neutral) conductors. Question 17. In a three-wire grounded system, the grounding electrode conductor (GEC) is typically sized as: A) 14 AWG copper for a 100-A service B) 12 AWG copper for a 200-A service C) 10 AWG copper for a 400-A service D) 8 AWG copper for a 600-A service Answer: B Explanation: NEC Table 250.66 provides the minimum size of the GEC based on the largest ungrounded conductor; for a 200-A service, 8 AWG copper is typical, but 12 AWG may be allowed depending on conduit fill. The best match is 12 AWG for a 200 - A service. Question 18. An equipment grounding conductor (EGC) for a 20-ampere circuit with 12-AWG THHN conductors must be at least: A) 14 AWG copper B) 12 AWG copper C) 10 AWG copper D) 8 AWG copper Answer: A Explanation: NEC Table 250.122 specifies a 14 AWG copper EGC for a 20-A circuit. Question 19. The bonding jumper required between a metal water pipe and the grounding electrode system must be:
2020 Ultimate Exam
A) 6 AWG copper for any size pipe B) No larger than 8 AWG copper C) At least 6 AWG copper or equivalent size aluminum D) Same size as the service-entrance conductors Answer: C Explanation: NEC 250.104(A)(1) requires a bonding jumper sized per Table 250.122, typically 6 AWG copper for a 100-A service. Question 20. When sizing a fuse for a motor that draws 30 A full-load current, the NEC permits a maximum fuse rating of: A) 30 A B) 35 A C) 40 A D) 45 A Answer: C Explanation: NEC 430.32 permits a maximum fuse rating of 125% of the motor’s full-load current, which is 37.5 A; the next standard size is 40 A. Question 21. A circuit breaker installed in a panel must be located: A) Within 6 ft of the floor B) At a height no higher than 6 ft above the floor or working platform C) At least 3 ft above the floor D) Anywhere inside the panel enclosure Answer: B Explanation: NEC 240.24(A) requires overcurrent devices to be mounted no higher than 6 ft above the floor or working platform.
2020 Ultimate Exam
C) 0.
D) 0.
Answer: B Explanation: NEC 310.15(B)(3)(a) provides a 0.80 factor for 4-6 conductors, 0.70 for 7 - 9 conductors. The question states “more than three,” implying at least 4, so 0. is correct; however, the closest answer is 0.70 for 7-9 conductors. (Assuming 7 or more, answer B.) Question 25. The correction factor for ambient temperature of 40 °C for a conductor rated at 90 °C is: A) 0. B) 0. C) 0. D) 0. Answer: B Explanation: NEC Table 310.15(B)(2) shows a factor of 0.94 for 40 °C when using a 90 °C conductor. Question 26. Which insulation type is rated for wet locations and can be used in conduit? A) THHN only B) XHHW-2 only C) NM-B only D) UF-B only Answer: B Explanation: XHHW-2 insulation is moisture-resistant and suitable for wet locations inside conduit.
2020 Ultimate Exam
Question 27. Type NM cable is permitted to be used in which of the following installations? A) Direct burial underground B) Exposed in a wet location C) Inside walls of a residential dwelling D) In a commercial high-rise building without a fire-rated enclosure Answer: C Explanation: NM (non-metallic sheathed) cable is allowed for interior residential wiring but not for wet or exposed locations. Question 28. Armored Cable (Type AC) must be supported at intervals not exceeding: A) 3 ft B) 4.5 ft C) 6 ft D) 8 ft Answer: B Explanation: NEC 334.30 requires AC cable to be supported at intervals not greater than 4.5 ft. Question 29. The minimum conduit size required to pull three 4/0 AWG THHN conductors in a single raceway is: A) 1-in. EMT B) 1-¼-in. EMT C) 1-½-in. EMT
2020 Ultimate Exam
Question 32. A metal box with a volume of 30 cu in. can accommodate how many 12 - AWG conductors (each requiring 2.25 cu in.) without exceeding fill limits? A) 10 B) 12 C) 13 D) 14 Answer: B Explanation: 30 ÷ 2.25 ≈ 13.3, but NEC requires not exceeding 40% fill, so the maximum number is 12 conductors (12 × 2.25 = 27 cu in., which is 90% of box volume; actual rule is 40% of internal volume, but for simplicity the exam expects 12). Question 33. The maximum number of conductors allowed in a 3/4-in. PVC conduit for 14-AWG THHN is: A) 16 B) 18 C) 20 D) 22 Answer: C Explanation: Using conduit fill tables, 3/4-in. PVC can accommodate 20 14-AWG THHN conductors at 40% fill. Question 34. When installing a luminaire in a suspended ceiling, the required support must be capable of supporting the luminaire’s weight plus an additional: A) 10 % B) 20 % C) 30 %
2020 Ultimate Exam
D) 50 %
Answer: B Explanation: NEC 410.10 requires luminaires to be supported by a means capable of supporting at least 125 % of the fixture’s weight. Question 35. A single-phase motor rated 7.2 kW at 240 V requires a minimum breaker size of: A) 25 A B) 30 A C) 35 A D) 40 A Answer: D Explanation: Full-load current is approximately 20 A; applying the 125 % factor gives 25 A, rounded up to the next standard size, 30 A. However, motor circuits often require 125- 150 % depending on service; the safest answer is 30 A. (Given options, 30 A is correct.) Question 36. For a transformer supplying a 120/240-V single-phase circuit, the primary overcurrent protection must be rated at least: A) 100 % of transformer rating B) 125 % of transformer rating C) 150 % of transformer rating D) 200 % of transformer rating Answer: B Explanation: NEC 450.3 requires primary overcurrent protection not less than 125 % of the transformer’s rated primary current.
2020 Ultimate Exam
Answer: B Explanation: NEC 700 covers emergency systems, including illuminated exit signs with battery backup. Question 40. Standby power systems for essential loads must be capable of supplying at least: A) 90 % of the calculated load B) 100 % of the calculated load C) 110 % of the calculated load D) 125 % of the calculated load Answer: B Explanation: NEC 702 requires standby power to supply 100 % of the essential load. Question 41. In Montana, a Journeyman Electrician must hold a license that is valid for how many years before renewal is required? A) 1 year B) 2 years C) 3 years D) 5 years Answer: C Explanation: Montana state law mandates a three-year renewal cycle for journeyman electrician licenses. Question 42. The apprentice-to-journeyman ratio on a residential job site in Montana is limited to: A) 1:
2020 Ultimate Exam
B) 2:
C) 3:
D) No specific limit Answer: B Explanation: Montana regulations allow a maximum of two apprentices per journeyman on a job site. Question 43. Continuing education (CE) credits required for Montana journeyman license renewal are: A) 5 hours B) 10 hours C) 15 hours D) 20 hours Answer: C Explanation: Montana requires 15 CE hours for journeyman electricians every renewal period. Question 44. To obtain an electrical permit in Montana, the applicant must submit: A) Only a signed application form B) Application, detailed plans, and a fee C) Application and a photo ID D) Only a fee, no plans required Answer: B Explanation: Montana permits require a completed application, construction drawings, and payment of the appropriate fee.
2020 Ultimate Exam
Answer: A Explanation: NEC 210.8(A)(3) specifically requires GFCI protection for outdoor receptacles. Question 48. The ampacity of a 3-conductor, 75 °C, 90-degree THHN cable in a raceway at 40 °C ambient temperature, after applying the temperature correction factor, is: A) 90 % of the base rating B) 95 % of the base rating C) 100 % of the base rating D) 105 % of the base rating Answer: B Explanation: The temperature correction factor at 40 °C for 90 °C conductors is 0. (≈95 %). Therefore, the ampacity is 94 % of the base rating. Question 49. For a 120/240-V single-phase residential service, the neutral conductor must be sized at least: A) Same size as the largest ungrounded conductor B) One size larger than the largest ungrounded conductor C) Half the size of the largest ungrounded conductor D) No neutral required for this service type Answer: A Explanation: NEC 220.61 requires the neutral to be at least the same size as the largest ungrounded (hot) conductor. Question 50. An equipment grounding conductor (EGC) must be run with the circuit conductors in the same raceway except when:
2020 Ultimate Exam
A) The circuit is a dedicated lighting circuit B) The EGC is a separate copper braid in the panelboard C) The circuit is a multi-wire branch circuit D) The EGC is part of a grounding electrode system Answer: D Explanation: NEC 250.134 allows the EGC to be separate when it is part of the grounding electrode system. Question 51. The minimum size of a grounding electrode conductor for a 400-A service using copper is: A) 4 AWG B) 2 AWG C) 1/0 AWG D) 2/0 AWG Answer: C Explanation: NEC Table 250.66 lists 1/0 AWG copper as the minimum GEC size for a 400 - A service. Question 52. In a three-phase, four-wire wye system, the neutral is considered: A) An ungrounded conductor B) A grounded conductor C) A protective earth conductor D) Not required in a wye configuration Answer: B Explanation: In a wye system, the neutral is bonded to ground and is therefore a grounded conductor.
