Texas Master Sign Electrician

(6 questions, 6% of the exam)

Key Concepts

Code structure, rules, and the AHJ - Purpose: "the practical safeguarding of persons and property from hazards arising from the use of electricity"; the Code is not a design specification or instruction manual for untrained persons — 90.2(A). - Compliance and proper maintenance give an installation "essentially free from hazard but not necessarily efficient, convenient, or adequate for good service or future expansion" — 90.2(B). - Not covered: ships, watercraft other than floating buildings, railway rolling stock, aircraft, automotive vehicles other than mobile homes and recreational vehicles; also installations underground in mines and self-propelled mobile surface mining machinery — 90.2(D). - Arrangement: introduction plus nine chapters. Chapters 1–4 apply generally; 5, 6, 7 cover special occupancies/equipment/conditions; Chapter 8 covers communications systems and is not subject to Chapters 1–7 except where specifically referenced; Chapter 9 is tables — 90.3. - Mandatory rules use "shall" or "shall not"…

Key Concepts

Number of services and identification. A building is supplied by only one service unless permitted by 230.2(A)–(D). Additional services are permitted for fire pumps, emergency systems, legally required standby, optional standby, interconnected electric power production sources, and multiple-source reliability systems [230.2(A)]; also where capacity requirements exceed 2000 amperes at 1000 volts or less [230.2(C)]. Where a building is supplied by more than one service, a permanent plaque or directory is required at each service disconnect location [230.2(E)]. Service conductors shall not pass through the interior of another building [230.3].

Service conductor size and insulation. Overhead service conductors shall not be smaller than 8 AWG copper or 6 AWG aluminum/copper-clad aluminum, except 12 AWG hard-drawn copper for limited loads of a single branch circuit [230.23(B)]. Service-entrance conductors entering or on the exterior of buildings shall be insulated, with the grounded-conductor exceptions of 230.41 (bare copper in a raceway or service cable assembly, etc.).…

Texas Master Sign Electrician | 3 questions (3% of exam)

Key Concepts

Scope. Article 215 covers the installation requirements, overcurrent protection requirements, minimum size, and ampacity of conductors for feeders not over 1000 volts ac or 1500 volts dc, nominal (NEC 215.1).

Minimum conductor ampacity (the 125% rule). Where a feeder supplies continuous loads or any combination of continuous and noncontinuous loads, the minimum feeder conductor size shall have an ampacity not less than the noncontinuous load plus 125 percent of the continuous load (NEC 215.2(A)(1)). Feeder conductors shall have an ampacity not less than the larger of 215.2(A)(1) or (A)(2) and shall comply with 110.14(C).

Key Concepts

• Branch-circuit ratings. "The rating for other than individual branch circuits shall be 10, 15, 20, 30, 40, and 50 amperes" (210.18). Exception No. 1 permits multioutlet branch circuits greater than 50 amperes for nonlighting outlet loads where only qualified persons service the equipment; Exception No. 2: "Branch circuits rated 10 amperes shall not supply receptacle outlets" (also 210.23(A)(2) and Table 210.24(1) footnote 2).
• Conductor ampacity — continuous loads. Conductors must have ampacity not less than the noncontinuous load plus 125 percent of the continuous load (210.19(A)(1)), and must comply with 110.14(C) for terminations (210.19(A)). Exception to (1): if the assembly including the overcurrent devices is listed for 100 percent operation, ampacity may be the sum of continuous plus noncontinuous load. Exception to (1) and (2): where a portion of the circuit connects at both ends to separately installed pressure connections per 110.14(C)(2), continuous plus noncontinuous is permitted.
• Overcurrent protection.…

Texas Master Sign Electrician | 8 questions (8% of exam)

Key Concepts

Conductor types, insulation and temperature limits (Article 310) - Minimum size of conductors for voltage ratings up to and including 2000 volts is 14 AWG copper or 12 AWG aluminum or copper-clad aluminum — 310.3(A). - Where installed in raceways, conductors 8 AWG and larger shall be stranded — 310.3(C). - Type THHN maximum operating temperature is 90°C (194°F) in dry and damp locations — Table 310.4(1). - Conductors may be connected in parallel only in sizes 1/0 AWG and larger — 310.10(G)(1). - The AWG size or circular mil area shall be repeated at intervals not exceeding 610 mm (24 in.) on surface-marked wire and cable — 310.8(B)(1). - Fixture wires in Table 402.13 are suitable for 600 volts, nominal, unless otherwise specified — 402.13.

Key Concepts

Scope note on the SOURCE. The verified questions and reference text supplied for this topic cover equipment and device rules found in Articles 400, 500, 600, 604, 605, 610, 700 and parts of Article 210. They do not contain the text of Articles 404, 406, 408, 410, 440, 445 or 450, so nothing below should be read as a statement of those articles' contents. Where a rule below points into Article 430 or 250, it does so only because the SOURCE text itself makes that cross-reference.

Crane and hoist disconnecting means (motor-related). A disconnecting means with a continuous ampere rating not less than that calculated in 610.14(E) and (F) shall be provided between the runway contact conductors and the power supply, and "the disconnecting means shall comply with 430.109." It must be readily accessible and operable from the ground or floor level, lockable open in accordance with 110.25, open all ungrounded conductors…

Key Concepts

Conductor sizing (Article 430, Part II). Conductors supplying a single continuous-duty motor must have an ampacity of not less than 125 percent of the motor full-load current rating, as determined by 430.6(A)(1) — 430.22. Per 430.6(A)(1), the values in Table 430.247 through Table 430.250 are used instead of nameplate current to determine conductor ampacity, switch ratings, and branch-circuit short-circuit and ground-fault protection ratings. Nameplate current is used for separate motor overload protection — 430.6(A)(2). Special multipliers: wye-start, delta-run conductors between controller and motor at 72 percent (430.22(C)); part-winding at 62.5 percent (430.22(D)); small-motor conductors not smaller than 14 AWG unless 430.22(G)(1) or (G)(2) applies. Conductor size is selected from the ampacity tables in 310.15 or calculated per 310.14(B) — 430.6.

Key Concepts

Sign and outline lighting disconnects (Article 600) - Each sign and outline lighting system, and the feeders or branch circuits supplying a sign, outline lighting system, or skeleton tubing, must be controlled by an externally operable switch or circuit breaker that opens all ungrounded conductors and controls no other load (600.6). Signs within fountains follow 680.13. - Exception No. 1: no disconnect required for an exit directional sign located within a building. Exception No. 2: no disconnect required for cord-connected signs with an attachment plug (600.6). - The disconnecting means shall be accessible and located per 600.6(A)(1), (A)(2), or (A)(3); if remote from the sign it controls, it must also comply with 600.6(A)(4). - (A)(1) Point of entry — at the point the feeder or branch circuits enter the sign enclosure, sign body, or pole, opening all ungrounded conductors. - (A)(2) Within sight of the sign — where out of the line…

Key Concepts

Listing & Marking - Fixed, mobile, or portable electric signs, section signs, outline lighting, PV powered signs, and retrofit kits, regardless of voltage, shall be listed and labeled, provided with installation instructions, and installed in conformance with that listing — 600.3. - Exceptions: field-installed skeleton tubing is not required to be listed where installed in conformance with the Code — 600.3(A); outline lighting need not be listed as a system when it consists of listed luminaires wired per Chapter 3 — 600.3(B). - Signs with lampholders for incandescent lamps: marked with maximum allowable lamp wattage per lampholder, permanently installed, letters at least 6 mm (¼ in.) high, visible during relamping — 600.4(C).