Download Iec year 1 final exam ACCURATE TESTED VERSIONS OF THE EXAM FROM 2025 TO 2026 | ACCURATE and more Exams Electrical Engineering in PDF only on Docsity!
IEC First Year Exam Study EXAM TEST
BANK WITH ALL VERSIONS OF THE
EXAM WITH ALLMODULES COVERED |
ACCURATE AND VERIFIED QUESTIONS
AND ANSWERS FOR GUARANTEED
PASS| LATEST UPDATE
1. When installing audio/video/data cables, how should the cables be handled? A. Be stapled tightly with metal staples B. Be kinked for tighter bends C. Be left unsecured to allow movement D. Not be kinked, secured with rounded staples, and loosely bundled with other cables ✅ Correct Answer: D Rationale: Proper cable management ensures signal integrity and prevents physical damage; NEC and best practices recommend avoiding kinks, using appropriate staples, and loose bundling. 2. Terminations of RG-6 cable are made using which type of connectors? A. RJ- 45 B. BNC C. F connectors only D. HDMI ✅ Correct Answer: C Rationale: RG-6 coaxial cable is typically terminated using F connectors for audio/video applications. 3. Home automation controllers that use RF signals: A. Cannot operate through walls B. Require line-of-sight C. Can send signals through walls D. Are limited to outdoor use ✅ Correct Answer: C Rationale: RF signals penetrate walls, enabling wireless control within a building. 4. A disconnecting means for a swimming pool circulation pump must be installed: A. Inside the pool equipment enclosure B. Exactly 3 feet from the pool
C. At least 5 feet from the pool and visible from the pump D. In the basement ✅ Correct Answer: C Rationale: NEC requires the disconnect to be at least 5 feet away and in sight for safety and serviceability.
5. Receptacles 6 to 10 feet from pool walls powering sanitation systems must be: A. Weatherproof only B. Ungrounded C. Grounding type with GFCI protection D. 50-amp rated ✅ Correct Answer: C Rationale: These receptacles must be grounded and GFCI-protected for poolside safety. 6. What is the minimum number of 125V, 15- or 20A receptacles required near a permanent pool? A. 0 B. 1 C. 2 D. 3 ✅ Correct Answer: B Rationale: NEC requires at least one convenience receptacle within 6–20 feet of a pool. 7. A 120V, 20A receptacle near a pool must be located how far from the pool edge? A. 3 feet B. 5 feet C. 6 feet D. 10 feet ✅ Correct Answer: C Rationale: NEC mandates pool receptacles be 6+ feet away to avoid shock hazards. 8. Safety switches near pools must be located at least how far from the water? A. 3 feet B. 4 feet C. 5 feet D. 6 feet ✅ Correct Answer: C Rationale: NEC requires at least 5 feet for protection from splashing and electrical hazards.
14. NEC limitations on OCPDs near combustible materials are specified at: A. 210. B. 250. C. Article 300 D. None ✅ Correct Answer: D Rationale: NEC does not specify restrictions here beyond general installation guidelines. 15. A breaker panel is permitted to be located where? A. Closet only B. Crawlspace C. In an electrical room or restaurant bathroom D. Under a sink ✅ Correct Answer: C Rationale: Panels are permitted in accessible locations including bathrooms in commercial buildings. 16. A disconnect with plug fuses supplied from a 277/480V breaker is a code violation? A. No B. Yes ✅ Correct Answer: B Rationale: Plug fuses are not permitted in circuits over 150V to ground. 17. Load centers are typically not available with “bolt-on” breakers. A. True B. False ✅ Correct Answer: A Rationale: Load centers use plug-in breakers; bolt-on types are for panelboards. 18. To determine the size of a grounding electrode conductor, refer to table: A. 220. B. 310. C. 250. D. 430. ✅ Correct Answer: C Rationale: Table 250.66 specifies GEC sizing based on conductor size. 19. The GEC must be connected within how many feet of metal water pipe entry? A. 1 foot B. 3 feet C. 5 feet
D. 10 feet ✅ Correct Answer: C Rationale: NEC requires connection within 5 feet of entry.
20. An equipment grounding conductor (EGC): A. Carries load current B. Is installed separately C. Is installed with branch circuit conductors D. Acts as a neutral ✅ Correct Answer: C Rationale: EGCs are installed with other conductors to ensure proper bonding. 21. The grounding blade on an attachment plug is ___ than the current-carrying blades. A. Shorter B. The same length C. Longer D. Insulated ✅ Correct Answer: C Rationale: The grounding blade is intentionally longer so it connects first and disconnects last, ensuring safety during plug-in and removal. 22. The initial cost of metal halide luminaires is ___ than quartz luminaires. A. Lower B. Higher C. The same D. Negligible ✅ Correct Answer: B Rationale: Metal halide fixtures typically cost more due to their design and application. 23. The conductors at point III in Figure 130.101 are ___. A. Service-drop conductors B. Feeder conductors C. Branch-circuit conductors D. Service-lateral conductors ✅ Correct Answer: D Rationale: Service-lateral conductors run underground from the utility to the service point. 24. Refer to Figure 130.104. Circuit 13 is connected to the ___ busbar. A. AØ B. BØ C. CØ D. Neutral
✅ Correct Answer: C Rationale: NEC Table 8, Chapter 9 specifies this dimension.
30. For conduit fill with conductors of the same size, refer to: A. Table 1 B. Article 310 C. Annex C D. Table 310. ✅ Correct Answer: C Rationale: Annex C of the NEC gives conduit fill tables by conductor size. 31. Table used for number of conductors in 80 PVC is: A. 8 B. 310.15(B)(3)(a) C. C.10, Annex C D. C. ✅ Correct Answer: C Rationale: Table C.10 in Annex C lists conductor fill for PVC conduits. 32. If voltmeter leads are placed at T3 and T4, the reading will be: A. 0 volts B. 120 volts C. 240 volts D. 277 volts ✅ Correct Answer: B Rationale: These points are across a single-phase load. 33. What is the minimum number of receptacles required in an unfinished basement? A. 0 B. 1 C. 2 D. 4 ✅ Correct Answer: B Rationale: NEC requires at least one receptacle in unfinished basements. 34. If the neutral is removed from the circuit shown, the voltage across lamp 2 is: A. 60V B. 80V C. 100V D. 120V ✅ Correct Answer: B Rationale: An open neutral causes voltage imbalances across loads.
35. The load will be energized when the switches are in which position? A. Both closed B. Either open C. Only one open D. None ✅ Correct Answer: D Rationale: According to the figure, none of the switch conditions complete the circuit. 36. Voltmeter reading at T1 and T8 will indicate: A. 120V B. 240V C. 0V D. 12V ✅ Correct Answer: C Rationale: The points are electrically common or disconnected. 37. How much current is flowing in the neutral conductor at point C in the figure? A. 0 B. 2 C. 4 D. 8 ✅ Correct Answer: B Rationale: The drawing shows 2A flowing due to unbalanced currents. 38. The neutral conductor is carrying how many amps? A. 1. B. 2. C. 2. D. 4. ✅ Correct Answer: B Rationale: Current values are determined from the load shown. 39. In a multi-wire circuit with 13A on one leg and 16A on the other, how much current flows in the shared neutral? A. 0A B. 3A C. 29A D. 13A ✅ Correct Answer: B Rationale: Current in the neutral = |I1 – I2| = 3A for opposing phases.
✅ Correct Answer: C Rationale: 0.3 kW × 4 = 1.2 kW total.
45. Short EMT runs between panels don’t require derating if shorter than: A. 12 in. B. 18 in. C. 24 in. D. 36 in. ✅ Correct Answer: C Rationale: Per NEC, runs under 24 inches may be exempt from ampacity adjustments. 46. Extension ladders must extend how far above the roofline? A. 2 ft. B. 3 ft. C. 4 ft. D. 5 ft. ✅ Correct Answer: B Rationale: OSHA requires 3 feet above the edge for safe access. 47. Monthly cost of operating a 250W lamp at $0.15/kWh for 8 hrs/day is: A. $6. B. $9. C. $12. D. $15. ✅ Correct Answer: B Rationale: 0.25kW × 8 hrs/day × 30 × $0.15 = $9. 48. The point where utility wiring ends and premises wiring begins is called: A. Load center B. Panelboard C. Service Point D. Meter ✅ Correct Answer: C Rationale: Service point marks the transition between utility and customer. 49. A 60W lamp running for 21 hrs consumes how many kWh? A. 1. B. 1. C. 1. D. 1. ✅ Correct Answer: B Rationale: 60W × 21 hrs = 1,260 Wh = 1.26 kWh
50. To minimize damage during faults, what should be minimized? A. Voltage B. Conductor length C. Fault time duration D. Temperature ✅ Correct Answer: C Rationale: Faster clearing reduces damage during a fault. 51. Article ___ of the NEC covers grounding and bonding. A. 200 B. 210 C. 250 D. 300 ✅ Correct Answer: C Rationale: NEC Article 250 addresses grounding and bonding requirements. 52. Are self-tapping sheet metal screws permitted for EGC connections in boxes? A. Yes B. No ✅ Correct Answer: B Rationale: NEC prohibits using sheet metal screws for bonding conductors due to unreliability. 53. Minimum conductor size for a 100A 120/240V 3-wire commercial service is: A. 4 AWG B. 3 AWG C. 2 AWG D. 1 AWG ✅ Correct Answer: B Rationale: NEC tables require 3 AWG copper for 100A service. 54. For noncoincident loads like HVAC and heating, calculate using: A. Average B. Total C. Larger D. Smaller ✅ Correct Answer: C Rationale: Only the larger of noncoincident loads is counted in service sizing. 55. A 3/0 AWG conductor is also referred to as: A. 300 B. 00 C. 000
When a portable generator provides power for frame-mounted receptacles only, the NEC ® ___ require the frame to be connected to a grounding electrode. - Ans - does not Transfer switches use a ___ to prevent the feedback of electricity between the generator power and the normal utility power.
- Ans - mechanical interlock It is permitted to run normal power conductors and optional standby power conductors in the same raceway or enclosure.
- Ans - true What is the result if the neutral wire becomes open on a multiwire circuit having unequal loads? Select one: a. The load of higher resistance would overheat and probably be damaged. b. The load of lesser resistance would overheat and probably be damaged. c. No effect until one load is turned off or opens. d. No effect. - ANSWER The load of higher resistance would overheat and probably be damaged. Refer to Figure 128.202. ___ volts are applied across the water heater element. Select one: a. 1 20 b. 2 40 c. 0 d. 480 - ANSWER 240
Circuits 7 and 9 share a neutral. This is a multiwire branch circuit. If Ckt. 7 is drawing 13 amps and Ckt. 9 is drawing 16 amps, how much current is flowing in the neutral? Select one: a. 3 b. 1 3 c. 2 9 d. 16 - ANSWER 3 The Code reference that specifies the type of disconnecting means (circuit breaker for example) that can be used on a multiwire branch circuit that feeds devices mounted on the same yoke [a stack switch or a duplex receptacle for example] is ___. Note: Select N/A (not applicable) if there is not an NEC® requirement. Select one: a. Article 100 b. 240.15(B)(1) c. 404.8(A) d. N/A - ANSWER 240.15(B)(1) Voltmeters are connected in ___ with the load when used to measure voltage across a load in a circuit. Select one: a. parallel b. series - ANSWER Parallel
c. 1 d. 0 - ANSWER 1 What part of the NEC® is a reference for calculating conduit fill where all conductors are the same size? Select one: a. Article 100 b. Table 310.15(B)(16) c. Annex C d. Table 314.16(A) - ANSWER Annex C From NEC® Table 8 in Ch 9, the overall diameter of a 1/0 bare stranded copper conductor is ___ inches. Select one: a.. 1855 b.. 074 c.. 372 d.. 486 e. .109 - ANSWER.
Eleven #12, five #10, and six #6 THHN/THWN conductors will be installed in a run of EMT. The smallest trade size EMT you can use is ___. Select one: a. 1 1/ b. 2 1/ c. 1
- 1/ d. 2 e. 1 - ANSWER 1-1/ The number of conductors permitted in 80 PVC is specified in Table ___. Select one: a. 310.15(B)(16) b. 3
c. 3
d. C.10, Annex C - ANSWER C.10, Annex C A short length of EMT is run between two panels. The ampacity values for the conductors in this EMT need not be derated, as long as the length of the EMT does not exceed ___. Select one: a. 12 inches
10 kW b. 240 kW c. 100 kW d. 24 kW - ANSWER 24 kW If a 95-watt lamp operates for 11 hours, the utility will bill for ___ kWh. Select one: a. 8. 636 b. 1
c.
d. 1. e. 1.158 - ANSWER 1. What is the monthly energy cost to operate a 200-watt high-pressure sodium lamp? Electricity costs $0.11 per kW-hr and the lamp will be ON for 12 hours per day. There are 30 days in a billing month. Select one: a. $
b. $
c. $15.
d. $6. e. $660 - ANSWER $7. To minimize conductor insulation damage and arcing damage to electrical equipment during a ground fault or a short circuit, ___ should be minimized. Select one: a. time duration of the fault b. ampere level of the fault current c. both a and b d. neither a nor b - ANSWER time duration of the fault Article ___ in the NEC® covers grounding and bonding of electrical systems. Select one: a. 4 22 b. 4 24 c. 250 d. 240 e. 280 - ANSWER 250 Self-tapping sheet metal screws (TEK screws) ___ permitted to be used to connect the equipment grounding conductor to a metal box.
