Exam Cheat Sheet · Quick Reference
Texas Master Sign Electrician
Texas · PSI Services Contractor
Verified, not estimated. Every figure below is drawn from the official exam structure we maintain — question counts, passing standard and topic weighting. Practice questions are grounded in the source law with statute citations. We omit any figure we can't verify rather than guess at it.
Total questions
100
Passing score
70%
Exam time
300 min
Administered by
PSI Services Contractor
Format
Reference materials allowed
Texas State Portion 100 questions
Definitions, Calculations, and Theory
6 Q · 6%
Branch-circuit, feeder, and service load calculations using Article 220 demand factors and tablesConductor ampacity tables and temperature correction/adjustment factors (Article 310)Overcurrent protection sizing, types, and location requirements (Article 240)Grounding and bonding system requirements, electrode types, and conductor sizing (Article 250)NEC code structure, mandatory vs. permissive rules, and authority having jurisdictionUnits of measurement, voltage ratings, and rounding of calculationsEquipment grounding conductor identification and sizingGeneral wiring method requirements including conductor installation and protection (Article 300)
Electrical Services, Service Equipment, and Separately Derived Systems
16 Q · 16%
Service conductor requirements: overhead and underground installation, clearances, and wiring methodsService disconnecting means: location, rating, number, and grouping requirementsService overcurrent protection: overload protection, ground-fault protection of equipment, and arc energy reductionGrounding and bonding of services and separately derived systems: system bonding jumpers, grounding electrode conductors, and grounding electrode systemSwitchboards, switchgear, and panelboards: installation, overcurrent protection, marking, and clearancesTransformer installation and overcurrent protection: dry-type, liquid-insulated, and transformer vaultsService load calculations: feeder and service sizing, demand factors, and continuous load requirementsSurge protection, emergency disconnects, and equipment connected on the supply side of service disconnect
Electrical Feeders
3 Q · 3%
Minimum feeder conductor ampacity for continuous and noncontinuous loads (125% rule and exceptions)Feeder overcurrent protection requirements and ratingsFeeder load calculations including demand factors for dwelling units, multifamily, and non-dwelling occupanciesFeeder conductor sizing for grounded and equipment grounding conductorsGround-fault protection of equipment for feeders rated 1000 amperes or moreSurge-protective device (SPD) requirements for feeders supplying dwelling and similar occupanciesFeeder conductor identification for grounded, ungrounded, and equipment grounding conductorsOutside feeder installation requirements including clearances, disconnecting means, and number of supplies to buildings
Branch Circuit Calculations and Conductors
15 Q · 15%
Minimum conductor ampacity for continuous and noncontinuous loads (125% rule)Branch circuit ratings and permissible loads by circuit size (10A through 50A+)Overcurrent protection sizing for branch circuits including standard ampere ratingsConductor ampacity tables and correction/adjustment factors for temperature and conduit fillGFCI protection requirements by location for dwelling and non-dwelling occupanciesAFCI protection requirements by occupancy type and means of protectionMultiwire branch circuit requirements including disconnecting means and line-to-neutral loadsDwelling unit load calculations including general lighting, small-appliance, laundry, and cooking appliance loads
Electrical Wiring Methods and Electrical Materials
8 Q · 8%
Conductor types, insulation ratings, and temperature limitations (Article 310)Ampacity tables and correction/adjustment factors for current-carrying conductorsProtection of cables and raceways against physical damage (boring, notching, framing members)Underground installation requirements including minimum cover depths and backfillSecuring and supporting requirements for raceways and cable assembliesBox and conduit body fill calculations and sizing requirementsUses permitted and not permitted for Type AC, MC, NM, NMC, SE, USE, and IMC wiring methodsWiring in environmental air-handling spaces, plenums, and ducts
Electrical Equipment and Devices
10 Q · 10%
Switch types, ratings, and load control requirements (Articles 404.14, 404.7, 404.8)Receptacle installation, grounding, and replacement requirements (Article 406)Switchboards, switchgear, and panelboard installation and overcurrent protection (Article 408)Luminaire installation locations, supports, grounding, and wiring requirements (Article 410)Motor branch-circuit conductors, overload protection, and disconnecting means (Article 430)Transformer overcurrent protection, installation types, and vault requirements (Article 450)Air-conditioning and refrigerating equipment branch-circuit and disconnecting means requirements (Article 440)Generator overcurrent protection, disconnecting means, and emergency shutdown requirements (Article 445)
Motors
2 Q · 2%
Motor branch-circuit conductor sizing and ampacity requirements (Article 430, Part II)Motor overload protection selection and settings (Article 430, Part III)Branch-circuit short-circuit and ground-fault protective device ratings and settings (Article 430, Part IV)Motor disconnecting means types, location, and ratings (Article 430, Part IX)Motor controller ratings, markings, and requirements (Article 430, Part VII)Motor nameplate markings and locked-rotor code letters (Article 430.7)Motor control centers installation, grounding, and overcurrent protection (Article 430, Part VIII)Adjustable-speed drive systems conductor sizing and overload protection (Article 430, Part X)
Electrical Control Devices and Disconnecting Means
4 Q · 4%
Types and ratings of disconnecting means for motors and motor circuits (Articles 430 Part IX, 440 Part II)Location requirements for motor disconnecting means — in-sight, lockable, accessibleService disconnecting means — location, rating, number of disconnects, and marking (Article 230 Part VI)Switch connections, grounded conductor switching rules, and three-way/four-way switch wiring (Article 404)Rating and use of switches — AC/DC snap switches, dimmers, CO/ALR, cord-and-plug-connected loads (404.14)Panelboard and switchboard overcurrent protection, circuit directories, and grounding requirements (Article 408)Motor controller requirements — ratings, horsepower, disconnecting means serving as controller (Article 430 Parts VII, IX)Overcurrent protection location, standard ratings, and arc energy reduction for fuses and circuit breakers (Article 240)
Electric Signs and Outline Lighting
36 Q · 36%
Branch circuit requirements for electric signs (ratings, amperage limits, dedicated circuits)Disconnecting means requirements (location, accessibility, lockable provisions, control switch rating)Grounding and bonding of sign equipment and metal partsListing, labeling, and marking requirements for signs and outline lighting systemsNeon secondary-circuit wiring (over and under 1000 volts, GTO cable, conduit methods, conductor spacing)Transformers, electronic power supplies, and Class 2 power sources (ratings, ground-fault protection, voltage limits)Enclosures and location requirements (wet locations, clearances from vehicles and combustibles, drain holes)Neon tubing, electrode connections, and support requirements
Key Distinctions
Neon tubing branch circuitvsAll other signs/outline lighting branch circuit
Neon tubing installations may be supplied by a branch circuit rated up to 30 amperes, while all other signs and outline lighting systems are limited to 20 amperes.
NEC 600.5(C)(1)Maximum secondary-circuit voltage (15,000 V)vsMaximum voltage to ground (7,500 V)
The total secondary-circuit voltage must not exceed 15,000 volts nominal under any load, but the voltage to ground of any single output terminal must not exceed 7,500 volts.
NEC 600.23(C)Secondary conductor max length in metal conduit (20 ft)vsSecondary conductor max length in nonmetallic conduit (50 ft)
From a high-voltage terminal to the first neon tube electrode, metal conduit limits the run to 6 m (20 ft), whereas nonmetallic conduit allows up to 15 m (50 ft).
NEC 600.32(J)(1)Required commercial sign outlet (20 A)vsMaximum branch circuit for neon (30 A)
NEC 600.5(A) mandates at least one 20-ampere dedicated outlet at each commercial occupancy for sign use, while 600.5(C)(1) separately allows neon tubing circuits to be rated up to 30 amperes.
NEC 600.5(A)Neon tubing spacing from nearest surface (1/4 in.)vsNonmetallic conduit spacing from grounded parts (1-1/2 in.)
Neon tubing itself must be kept at least 6 mm (1/4 in.) from any adjacent surface other than its support, while nonmetallic conduit carrying a conductor at 100 Hz or less must be at least 38 mm (1-1/2 in.) from grounded or bonded parts.
NEC 600.41(C)Listed/labeled requirement — fixed signsvsListed/labeled requirement — mobile/portable signs
NEC 600.3 requires all electric signs to be listed and labeled regardless of whether they are fixed, mobile, or portable, and regardless of voltage.
NEC 600.3Minimum conduit size for neon secondary circuit (trade size 1/2)vsMinimum conductor size for neon secondary circuit (18 AWG)
Conduit or tubing for neon secondary circuits over 1000 V must be at least metric designator 16 (trade size 1/2), while the conductors inside must be type GTO and not smaller than 18 AWG.
NEC 600.32(A)(3)Sign height above vehicle areas (14 ft)vsWorking space at transformers/power supplies (3 ft × 3 ft × 3 ft)
Equipment above vehicle-accessible areas must be at least 4.3 m (14 ft) high per NEC 600.9(A), whereas a separate 900 mm × 900 mm × 900 mm (3 ft cube) working space is required at each transformer or power supply not mounted inside a sign per NEC 600.21(D).
NEC 600.9(A)Flexible metal conduit as bonding means (max 100 ft total)vsStandard equipment bonding
Listed flexible metal conduit or liquidtight flexible metal conduit enclosing neon secondary conductors may serve as the bonding means only if the total accumulative length in the secondary circuit does not exceed 30 m (100 ft); beyond that length a separate bonding conductor is required.
NEC 600.7(B)(4)Key Terms
Listed and Labeled Requirement (NEC 600.3) NEC 600.3
Per NEC 600.3, all fixed, mobile, or portable electric signs, section signs, outline lighting, PV-powered signs, and retrofit kits, regardless of voltage, must be listed and labeled and installed in conformance with that listing.
Commercial Sign Outlet Requirement (NEC 600.5(A)) NEC 600.5(A)
Per NEC 600.5(A), each commercial building or occupancy accessible to pedestrians must have at least one dedicated outlet rated at least 20 amperes for sign or outline lighting use.
Neon Branch Circuit Rating (NEC 600.5(C)(1)) NEC 600.5(C)(1)
Per NEC 600.5(C)(1), branch circuits supplying neon tubing installations shall not be rated in excess of 30 amperes.
Non-Neon Sign Branch Circuit Rating (NEC 600.5(C)(2)) NEC 600.5(C)(2)
Per NEC 600.5(C)(2), branch circuits supplying all signs and outline lighting systems other than neon tubing shall be rated not to exceed 20 amperes.
Vehicle Clearance Height (NEC 600.9(A)) NEC 600.9(A)
Per NEC 600.9(A), sign or outline lighting system equipment must be installed at least 4.3 m (14 ft) above areas accessible to vehicles unless protected from physical damage.
Maximum Secondary-Circuit Voltage (NEC 600.23(C)) NEC 600.23(C)
Per NEC 600.23(C), the secondary-circuit voltage of transformers and electronic power supplies shall not exceed 15,000 volts nominal under any load condition, and voltage to ground of any output terminal shall not exceed 7,500 volts.
Maximum Secondary-Circuit Current (NEC 600.23(D)) NEC 600.23(D)
Per NEC 600.23(D), transformers and electronic power supplies used with electric signs shall have a secondary-circuit current rating of not more than 300 mA.
Neon Secondary Conductor Length — Metal Conduit (NEC 600.32(J)(1)) NEC 600.32(J)(1)
Per NEC 600.32(J)(1), secondary circuit conductors from a high-voltage terminal to the first neon tube electrode must not exceed 6 m (20 ft) when installed in metal conduit, or 15 m (50 ft) in nonmetallic conduit.
Neon Tubing Surface Spacing (NEC 600.41(C)) NEC 600.41(C)
Per NEC 600.41(C), neon tubing must maintain a minimum spacing of 6 mm (1/4 in.) from the nearest adjacent surface other than its support.
Nonmetallic Conduit Spacing from Grounded Parts (NEC 600.32(A)(4)) NEC 600.32(A)(4)
Per NEC 600.32(A)(4), nonmetallic conduit containing a neon secondary conductor operating at 100 Hz or less must be spaced at least 38 mm (1-1/2 in.) from any grounded or bonded part.
Minimum Conduit Size — Neon Secondary Circuit (NEC 600.32(A)(3)) NEC 600.32(A)(3)
Per NEC 600.32(A)(3), conduit or tubing used for neon secondary circuits over 1000 V shall be a minimum of metric designator 16 (trade size 1/2).
GTO Cable / Minimum Conductor Size (NEC 600.32(B)) NEC 600.32(B)
Per NEC 600.32(B), conductors for neon secondary circuits over 1000 V must be listed gas tube sign and ignition cable type GTO and shall not be smaller than 18 AWG.
Flexible Metal Conduit as Bonding Means (NEC 600.7(B)(4)) NEC 600.7(B)(4)
Per NEC 600.7(B)(4), listed flexible metal conduit or liquidtight flexible metal conduit enclosing neon secondary conductors may serve as the bonding means provided the total accumulative length does not exceed 30 m (100 ft).
Working Space at Transformers/Power Supplies (NEC 600.21(D)) NEC 600.21(D)
Per NEC 600.21(D), a working space at least 900 mm × 900 mm × 900 mm (3 ft × 3 ft × 3 ft) must be provided at each ballast, transformer, electronic power supply, or Class 2 power source not installed inside a sign.
Sheet Steel Minimum Thickness (NEC 600.8(C)) NEC 600.8(C)
Per NEC 600.8(C), sheet steel used in sign and outline lighting system enclosures must be at least 0.41 mm (0.016 in.) thick.
Maximum Lamp Wattage Marking (NEC 600.4(C)) NEC 600.4(C)
Per NEC 600.4(C), electric signs with incandescent lamp holders must be marked with the maximum allowable lamp wattage in letters at least 6 mm (1/4 in.) high.