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Texas - Master Sign Electrician
Texas · PSI Services Contractor
Porción Estatal de Texas 100 preguntas
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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)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)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)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 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)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 600.3Conduit 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)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)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)