Exam Cheat Sheet · Quick Reference
North Carolina Electrical Contractor - Single-Family Detached Residential Dwelling (SP-SFD)
North Carolina · PSI Services Contractor
North Carolina State Portion 40 questions
Key Distinctions
Chapter 8 is NOT subject to the requirements of Chapters 1 through 7 except where those requirements are specifically referenced in Chapter 8.
NEC 2020 Section 90.3Informational notes are included for informational purposes only and are not enforceable as requirements of the Code.
NEC 2020 Section 90.5(C)A straight pull requires length not less than 8 times the trade size of the largest raceway, while an angle or U pull requires not less than 6 times the largest raceway trade size plus the sum of the diameters of the other raceway entries in the same row.
NEC 2020 Section 314.28(A)(1)220.82(B) takes 100 percent of the first 10 kVA plus 40 percent of the remainder, while 220.83(A) (no additional air-conditioning or electric space-heating equipment being installed) takes the first 8 kVA at 100 percent and the remainder at 40 percent.
NEC 2020 Section 220.82(B)Two-circuit installations require a disconnect rated not less than 30 amperes, while the one-family dwelling's feeder disconnecting means must be rated not less than 100 amperes, 3-wire.
NEC 2020 Section 225.39(B)The 100-ampere minimum applies specifically to the one-family dwelling's feeder disconnect; a detached structure such as a garage supplied by a feeder falls under the 'all others' category at not less than 60 amperes unless it serves as the dwelling's main disconnect.
NEC 2020 Section 225.39(C)An equipment grounding conductor is run with the supply conductors and connected to the building disconnecting means and grounding electrode(s), but any installed grounded conductor shall NOT be connected to the equipment grounding conductor or to the grounding electrode(s) at the separate building or structure.
NEC 2020 Section 250.32(B)(1)For 'all other motors' (no marked service factor of 1.15 or greater, temperature rise over 40°C), 430.32(A)(1) sizes the overload at 115 percent of nameplate FLC, and 430.32(C) permits a larger device whose trip current shall not exceed 130 percent; the 140 percent figure applies only to motors with a marked service factor of 1.15 or greater or the corresponding marked temperature rise.
NEC 2020 Section 430.32(C)Where the panelboard assembly is not listed for 100 percent operation, the conductor ampacity must be the noncontinuous load plus 125 percent of the continuous load; the simple sum of the loads is permitted only where the assembly is listed for 100 percent operation.
NEC 2020 Section 215.2(A)(1)(a)Kitchen countertop receptacles specified by 210.52(B) must be served by the required 20-ampere small-appliance branch circuits, not by 15-ampere general-purpose circuits.
NEC 2020 Section 210.11(C)(1), 210.52(B)A master alarm box is publicly accessible and can ALSO be operated by remote initiating devices or an auxiliary alarm system, whereas an auxiliary alarm box can only be operated from remote initiating devices or an auxiliary system and a publicly accessible alarm box houses only a manually operated transmitter.
NFPA 72 National Fire Alarm and Signaling Code, Chapter 3 — 3.3.12 Alarm Box (3.3.12.1, 3.3.12.4, 3.3.12.5)A C corporation allows an unlimited number of shareholders with no personal liability and is taxed at the corporate level with a further tax on dividends (double taxation), while an S corporation is limited to 100 shareholders and uses pass-through taxation.
NASCLA Contractors Guide, North Carolina Electrical (14th ed.), Chapter 2 — Summary of Business Legal Structures tableA sole proprietor's assumed name certificate is filed at the Register of Deeds in each county of operation (there is no statewide name registration for sole proprietorships or general partnerships), while the Secretary of State handles corporations, LLCs, and limited partnerships.
NASCLA Contractors Guide, North Carolina Electrical (14th ed.), Chapter 2 — Naming Your Business / Assumed Name Filing sectionKey Terms
Formulas to Know
Length ≥ 8 × trade size of the largest raceway. Worked example: largest raceway 3 in. (with two 2-in. conduits also entering) → 8 × 3 = 24 in. minimum.Distance ≥ (6 × trade size of largest raceway in the row) + sum of the diameters of all other raceway entries in that same row. Worked examples: 2 in. + 1 in. entries → (6 × 2) + 1 = 13 in.; 4 in. + 2 in. entries → (6 × 4) + 2 = 26 in. governs (the 2-in. entry yields (6 × 2) + 4 = 16 in.).General load = 100% of the first 10 kVA + 40% of the remainder of the listed loads (not less than).Load = 100% of the first 8 kVA of existing and new load + 40% of the remainder.Include the largest of the listed selections; with four or more separately controlled electric space-heating units, 220.82(C)(5) permits 40% of nameplate. Worked example: 20 kVA × 0.40 = 8 kVA heating vs. 100% of 5 kVA A/C → include 8 kVA. (65% applies only where there are fewer than four separately controlled units.)Conductors are permitted to have an ampacity not less than 83% of the service rating. Worked example: 200 A × 0.83 = 166 A.Ampacity ≥ noncontinuous load + 125% of continuous load. Worked example: 28 A + (36 A × 1.25 = 45 A) = 73 A.Initial size = 115% of nameplate FLC (430.32(A)(1)); if that will not start the motor or carry the load, 430.32(C) permits a larger device whose trip current shall not exceed 130% of nameplate FLC. Worked example: 28 A × 1.15 = 32.2 A initial; maximum 28 A × 1.30 = 36.4 A.Ampacity ≥ 72% of the motor full-load current rating (58% carried by individual conductors × 1.25 = 72%).OCPD shall not exceed 150% of the appliance rated current; where 150% does not correspond to a standard rating, the next higher standard rating from 240.6(A) is permitted. Worked example: 22 A × 1.50 = 33 A → 35 A.