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What type of motors must be used in Class II, Division locations? | nec_codebook |
In a garage, unenclosed equipment that may produce arcs or sparks must be placed at least what height above the floor? | nec_codebook |
# Which circuit is one in which spark or thermal effect is incapable of causing ignition of a mixture of flammable or combustible material in air under prescribed test conditions? | nec_codebook |
What type of location is classified as a location in which flammable gases, flammable liquid-produced vapors, or combustible liquid-produced vapors are or may be present in the air in quantities sufficient to produce explosive or ignitible mixtures? | nec_codebook |
What type of hazardous location is classified as a location where ignitible concentrations of flammable liquid-produced vapors or combustible liquid-produced vapors can exist under normal operating conditions? | nec_codebook |
What type of hazardous location is classified as a location where ignitible concentrations of flammable gases, flammable liquid-produced vapors, or combustible liquids above their flashpoints may exist frequently because of repair or maintenance operations or because of leakage? | nec_codebook |
Which type of hazardous location might release ignitible concentrations of flammable gases, flammable liquid-produced vapors or combustible liquid-produced vapors; and might also cause simultaneous failure of electric equipment? | nec_codebook |
Which method of bonding is acceptable for equipment installed in a Class location? | nec_codebook |
When surge arresters are installed in hazardous locations, what type of enclosure must be used? | nec_codebook |
If resistors and resistance devices are installed in Class II locations, what type of enclosures must be provided for them? | nec_codebook |
If listed cables are installed in a cable tray in Class II, Division 2 location, what is the minimum separation distance between them? | nec_codebook |
When installing conduit in Class III locations, what types of contacts shall not be depended upon for bonding purposes? | nec_codebook |
Conduits, cable trays, and open wiring used on intrinsically safe systems shall be identified by permanently affixed labels. What is the maximum distance allowable between labels? | nec_codebook |
What is the closest distance allowed for conductors and cables of intrinsically safe circuits (not in raceways or cable trays)? | nec_codebook |
# What color is used to identify intrinsically safe conductors? | nec_codebook |
# Which of the following wiring methods are allowed for fixed wiring above Class I locations? | nec_codebook |
# Electrical equipment installed above Class I locations, but less than 12 feet above floor level and that may produce sparks or hot metal particles, must be of what type? | nec_codebook |
# What must be provided on all 125-volt circuits installed in commercial garages for portable lighting devices? | nec_codebook |
# How is any pit or depression below the floor level of an aircraft hangar classified? | nec_codebook |
# Up to what level above the floor is the entire area of an aircraft hangar, not suitably cut off, classified as a Class I, Division 2 or Zone 2 location? | nec_codebook |
# Areas within 5 feet horizontally from aircraft power plants or aircraft fuel tanks are classified as Class I, Division 2 or Zone 2 locations. How far vertically does this area extend? | nec_codebook |
# Which of the following fixed wiring systems is not allowed in aircraft hangars outside Class locations? | nec_codebook |
# When an aircraft is stored in a hangar, what provisions must be provided for the aircraft's electrical system? | nec_codebook |
How far above floor level must all electric equipment on aircraft energizers be located? | nec_codebook |
# Which of the following may not be used for fixed wiring in bulk storage plants above Class locations? | nec_codebook |
# The interior of paint spray booths and rooms are classified as which hazardous area? | nec_codebook |
Which one of the following wiring methods is approved for fixed wiring above Class I or Class II locations in spray booth areas? | nec_codebook |
What means of grounding the terminals of receptacles (over 100 volts) is required in areas used for patient care in health care facilities? | nec_codebook |
What is the minimum number of branch circuits allowed at each patient bed location? | nec_codebook |
What is the minimum number of receptacles required at each patient bed location? | nec_codebook |
What must circuits classified as life safety branch and critical branch of the emergency electrical system in health care facilities be? | nec_codebook |
What is the minimum number of power sources for essential electrical systems in health care facilities? | nec_codebook |
Which of the following is not approved as an alternate power source for essential electrical systems in health care facilities? | nec_codebook |
Where must the alternate power for a health care facility be located? | nec_codebook |
In a health care facility, what is required for receptacles supplied from the emergency system? | nec_codebook |
What are some of the items falling under the category of electrical equipment which supplement or modify the general NEC rules? | nec_codebook |
What does Article 670 of the NEC cover? | nec_codebook |
How does the NEC define the type of transformers used in the construction of a sign? | nec_codebook |
What type of lamps do signs operating at over 600 volts typically employ according to the NEC? | nec_codebook |
Where are control wiring and feeder connection terminals usually installed on nonportable, electrically driven machines? | nec_codebook |
How is the heating effect of induction and dielectric heat generating equipment accomplished according to the NEC? | nec_codebook |
What does Article 630 of the NEC cover? | nec_codebook |
What does Article 645 of the NEC cover? | nec_codebook |
What does Article 680 of the NEC cover? | nec_codebook |
What does Article 675 of the NEC cover? | nec_codebook |
What does Article 668 of the NEC cover? | nec_codebook |
What does Article 669 of the NEC cover? | nec_codebook |
What does Article 620 of the NEC cover? | nec_codebook |
What does Article 626 of the NEC cover? | nec_codebook |
What does Article 694 of the NEC cover? | nec_codebook |
What does Article 685 of the NEC cover? | nec_codebook |
What does Article 604 of the NEC cover? | nec_codebook |
What does Article 605 of the NEC cover? | nec_codebook |
What does Article 650 of the NEC cover? | nec_codebook |
What does Article 690 of the NEC cover? | nec_codebook |
What does Article 640 of the NEC cover? | nec_codebook |
What does Article 660 of the NEC cover? | nec_codebook |
Switches or similar devices controlling a transformer in a sign must have a rating based on what? | nec_codebook |
What is the maximum length allowed for cords supplying portable signs in a dry location? | nec_codebook |
What is the smallest size conductor permitted for wiring neon secondary circuits rated at 1000 volts or less? | nec_codebook |
In wet locations, which of the following must be used to close the opening between neon tubing and a receptacle? | nec_codebook |
The installation of equipment having an open current voltage exceeding 1000 volts is not allowed in which of the following occupancies? | nec_codebook |
Which of the following wiring methods is suitable for underfloor wiring in a computer room? | nec_codebook |
What is the minimum height at which lighting fixtures above a spa or hot tub without GFCI protection must be installed? | nec_codebook |
In general, overhead conductors must not pass directly over a pool or horizontally within how many feet of the inside walls of the pool? | nec_codebook |
If the phase-to-neutral voltage in a three-phase system is 2400 volts, approximately how much is the phase-to-phase voltage? | nec_codebook |
What is the purpose of the clearances for overhead conductors above swimming pools when the voltage is 750 volts or less? | nec_codebook |
If utility-owned low-voltage communication, radio, and television coaxial cables pass directly over a pool, what is the minimum height required? | nec_codebook |
How far below the water line must a typical wet-niche fixture be installed? | nec_codebook |
What is the smallest bonding conductor permitted for pool equipment? | nec_codebook |
Which of the following is the smallest permitted equipment grounding conductor from a junction box to a panelboard supplying poolside equipment? | nec_codebook |
What is the maximum voltage between conductors for lighting fixtures in pools and fountains? | nec_codebook |
Power-supply cords for information technology equipment cannot exceed how many feet in length? | nec_codebook |
What are power cables installed under raised floors for information technology equipment not required to be? | nec_codebook |
How should information technology equipment be bonded to the system in accordance with NEC Article 250? | nec_codebook |
What is the maximum dc voltage allowed for the transformer-type rectifier in the previous question? | nec_codebook |
What NEC rating is given to a piece of X-ray equipment with a rating based on an operating interval of 5 minutes or longer? | nec_codebook |
What is the minimum size fixture wire permitted for the control and operating circuits of X-ray and auxiliary equipment? | nec_codebook |
Which one of the following locations generally prohibits the use of heating equipment? | nec_codebook |
If the phase-to-neutral voltage in a three-phase system is 2400 volts, approximately how much is the phase-to-phase voltage? | nec_codebook |
What is the minimum conductor ampacity required for a three-phase capacitor operating at 480 volts with a rated current of 120.4 amperes? | nec_codebook |
Why is it important to have overcurrent protection for capacitors when they are switched into a circuit? | nec_codebook |
What is the typical range for the setting of overcurrent protection for capacitors in electrical installations? | nec_codebook |
Why must capacitors be enclosed, guarded, or located out of reach in most installations? | nec_codebook |
If the phase-to-neutral voltage in a three-phase system is 2400 volts, approximately how much is the phase-to-phase voltage? | nec_codebook |
If an oil-insulated transformer installation presents a fire hazard, what safeguards must be used according to the degree of hazard? | nec_codebook |
Where must dry-type transformers rated over 35,000 volts be installed? | nec_codebook |
What is required for potential transformers installed indoors? | nec_codebook |
Capacitor circuit conductors must have an ampacity at least what percent of the rated current of the capacitor? | nec_codebook |
A capacitor operating at 300 volts must be discharged to what voltage within a minute after it is disconnected from its supply? | nec_codebook |
Unless specified otherwise in the NEC, what does the term "fire resistant" mean in terms of construction rating? | nec_codebook |
What type of enclosure must dry-type transformers installed outdoors have? | nec_codebook |
What must be provided in each ungrounded conductor for each capacitor bank? | nec_codebook |
Each transformer over 600 volts must be protected by an individual overcurrent device on the primary side. What is the maximum continuous current rating allowed for the fuse in an unsupervised location? | nec_codebook |
What is the main purpose of transformer taps? | nec_codebook |
In reference to transformers, voltage warning, mechanical protection, and enclosures are all examples of which of the following? | nec_codebook |
Each autotransformer; 600 volts nominal or less, shall be protected by an individual overcurrent device installed in series with each ungrounded input conductor: Such devices shall be rated or set at not more than what percent of the rated full-load input current of the autotransformer? | nec_codebook |
What amount of flammable liquid qualifies a capacitor for enclosure in a vault or an outdoor fenced enclosure? | nec_codebook |
What should the rating of an overcurrent device used on each ungrounded conductor for a capacitor bank 600 volts or less be? | nec_codebook |
How much space between resistors and reactors and any combustible material requires a thermal barrier to be provided? | nec_codebook |