eep April 10, 2025 NEC 400-490 NEC Quizzes Report a question What’s wrong with this question? You cannot submit an empty report. Please add some details. 0% Article 400-490 Part03 This quiz consists of 50 carefully selected questions covering NEC Articles 400 through 490, which provide critical guidelines for flexible cords and cables (Article 400), switchgear and control equipment (Article 409), and installations operating above 1000 volts (Article 490). These sections of the National Electrical Code focus on safety, material specifications, and proper installation practices. The randomly generated questions ensure a thorough assessment of your understanding, reinforcing key principles related to permitted uses of flexible cords, ampacity ratings, industrial control panels, and high-voltage equipment requirements. Some topics may reappear in different contexts to strengthen comprehension and application. Your feedback is invaluable! If you notice any discrepancies or have suggestions for improvement, please report them. Your insights help maintain the accuracy and effectiveness of this learning tool. Overcurrent protection ensures safe operation of lighting tracks. 1 / 50 How must heavy-duty lighting track fittings be protected (410.153)? a. No additional protection is needed. b. Only lightweight fittings are allowed. c. Each fitting must have individual overcurrent protection. d. Fittings must be grounded. Incorrect. Individual overcurrent protection is required for heavy-duty fittings. Correct! Overcurrent protection is mandatory for each fitting. Heavy-duty lighting track fittings must have individual overcurrent protection to handle the increased load safely. Heating equipment requires a dedicated circuit for safe operation. 2 / 50 How must central heating equipment be supplied (422.12)? a. From multiple branch circuits. b. Using any available circuit. c. By an individual branch circuit, with exceptions. d. With flexible cord connections only. Incorrect. An individual branch circuit is required with limited exceptions. Correct! An individual branch circuit is typically required. Central heating equipment must be supplied by an individual branch circuit, except for auxiliary or associated equipment like pumps or air conditioners, which can share the circuit. Heat management is crucial for safety near combustibles. 3 / 50 What is required for luminaires near combustible material (410.11)? a. They must be equipped with shades or guards to prevent temperatures exceeding 90°C. b. Combustible materials must be removed. c. No special requirements. d. They must be at least 10 feet away. Incorrect. Proper guards or shades are mandatory. Correct! Shades or guards prevent overheating near combustibles. Luminaires must have shades or guards to ensure that adjacent combustible materials do not exceed 90°C. Minimum mounting height ensures safety from UV exposure. 4 / 50 What is required for germicidal luminaires in occupied spaces (410.195(D))? a. They must include a user warning. b. They can be mounted at any height. c. They must not be mounted below the minimum height specified by their listing. d. No restrictions apply to their height. Incorrect. Mounting height must follow the luminaire’s listing. Correct! Germicidal luminaires have minimum mounting height requirements. Germicidal luminaires must comply with their listing’s specified minimum height to avoid harmful exposure to occupants. Listing ensures safety for seasonal or decorative lighting. 5 / 50 What must decorative lighting be listed for (410.160)? a. Outdoor use exclusively. b. Temporary installations only. c. Use for holiday and similar decorative purposes. d. A maximum of 120 volts. Incorrect. Decorative lighting must be listed for holiday or similar purposes. Correct! Listing ensures safety for holiday or similar decorative use. Decorative lighting must be listed for holiday or similar purposes to meet safety standards during temporary use. Dishwashers are subject to specific GFCI protection requirements. 6 / 50 What GFCI protection is required for dishwashers (422.5(A)(7))? a. Only for portable dishwashers. b. GFCI protection is not required for dishwashers. c. GFCI protection is optional for dishwashers. d. Class A GFCI protection for dishwashers at 150 volts or less to ground. Incorrect. Dishwashers require Class A GFCI protection under these conditions. Correct! Class A GFCI protection is required for dishwashers. Dishwashers at 150 volts or less to ground must have Class A GFCI protection to safeguard against electrical shock. Disconnecting means provide safe access for servicing appliances. 7 / 50 What is required for disconnecting means for permanently connected appliances over 300 volt-amperes (422.31(B))? a. A branch-circuit breaker or switch within sight or capable of being locked open. b. Disconnecting means are not required. c. Only a lockable circuit breaker. d. A separate switch located in the same room. Incorrect. NEC requires specific disconnecting means for these appliances. Correct! A circuit breaker or lockable switch is required. Appliances over 300 volt-amperes must have a branch-circuit breaker or switch within sight or capable of being locked open, ensuring safe servicing. Damp location luminaires need specific markings for identification. 8 / 50 What marking is required for luminaires suitable for damp locations (410.10(A))? a. Marked with a temperature rating. b. Marked as suitable for wet or damp locations. c. Marked as suitable for wet locations only. d. No marking is needed. Incorrect. Damp location suitability must be clearly marked Correct! The marking ensures proper use in damp locations. Luminaires suitable for damp locations must be marked either for wet or damp locations as per NEC requirements. Fans require specific support to ensure safety. 9 / 50 How must ceiling-suspended fans be supported (422.18(A))? a. With a listed outlet box or system identified for fan support. b. With temporary hanging brackets. c. Support is optional for lightweight fans. d. Using any available ceiling structure. Incorrect. Fans require specific listed support systems. Correct! Listed support systems are mandatory for ceiling fans. Ceiling-suspended fans must be supported by a listed outlet box or system identified for fan support to handle the weight and motion of the fan safely. Spacing prevents overheating and ensures proper heat distribution. 10 / 50 What is required for heating cables installed in ceilings (424.36)? a. They can be installed directly on conductive surfaces. b. They must be secured with metal fasteners c. They must be spaced at least 2 inches above the heated ceiling. d. They do not require special spacing. Incorrect. Spacing must be at least 2 inches above the ceiling. Correct! A minimum 2-inch clearance is required. Heating cables must maintain at least 2 inches of clearance from the heated ceiling to comply with NEC requirements. Subdivision minimizes the risk of short-circuit energy. 11 / 50 How must heating elements in boilers rated over 48 amperes be subdivided (425.22(B))? a. Into circuits not exceeding 100 amperes. b. Into circuits not exceeding 48 amperes. c. Into circuits based on operating temperature. d. Subdivision is optional for boilers. Incorrect. The correct subdivision limit is 48 amperes per circuit. Correct! Circuits must not exceed 48 amperes for safety. Heating elements in boilers rated over 48 amperes must be subdivided into circuits, each not exceeding 48 amperes, to limit damaging short-circuit energy. Voltage limits in dwellings ensure user safety. 12 / 50 What is the maximum open-circuit voltage for electric-discharge lighting systems in dwellings (410.135(B))? a. 600 volts. b. 300 volts. c. 300 volts or less. d. No limit if shielded. Incorrect. The voltage limit is 300 volts or less. Correct! 300 volts is the maximum for dwellings. Electric-discharge lighting systems in dwellings must have open-circuit voltages of 300 volts or less to reduce risks. The NEC restricts certain types of luminaires to minimize fire hazards. 13 / 50 What is prohibited for luminaires in clothes closets (410.16(C))? a. Fluorescent luminaires. b. LED luminaires. c. Surface-mounted luminaires. d. Pendant luminaires or lampholders. Incorrect. Pendant luminaires or lampholders are prohibited in closets. Correct! Pendant luminaires or lampholders are not permitted in clothes closets. Pendant luminaires or lampholders are not allowed in clothes closets to reduce the risk of contact with combustibles. NEC outlines specific requirements for concealed conductors in low-voltage systems. 14 / 50 How must conductors concealed through walls, floors, or ceilings be installed (411.6(A))? a. Using any available wiring method. b. Installed with no restrictions if low-voltage. c. Using wiring methods specified in Chapter 3 or wiring supplied by a Class 2 power source installed per 725.130. d. Directly connected without protection. Incorrect. Concealed conductors must meet specific NEC wiring requirements. Correct! Conductors must follow Chapter 3 or NEC 725.130 methods. Concealed conductors must comply with Chapter 3 wiring methods or use wiring from a Class 2 power source installed per NEC 725.130 to maintain safety and compliance. Nameplates provide essential information for safe installation and operation. 15 / 50 What markings must nameplates on fixed industrial process heating equipment include (425.28(A))? a. Only the manufacturer’s name. b. Installation date and frequency. c. Voltage, wattage or amperage, and manufacturer’s name. d. Voltage and amperage only. Incorrect. The nameplate must display detailed specifications, not just the manufacturer’s name. Correct! Nameplates must include these essential details. Nameplates must include the manufacturer’s name and the equipment’s ratings in voltage, wattage, or amperage to ensure proper identification and compliance. Sizing ensures safe operation during prolonged use. 16 / 50 How must branch-circuit conductors for fixed space-heating equipment be sized (424.4(B))? a. 125% of the load of the heaters and associated motors. b. 100% of the load. c. Based on the total connected load. d. There are no specific sizing requirements. Incorrect. The NEC requires a 125% ampacity for safety Correct! Conductors must be sized to handle 125% of the load. Branch-circuit conductors must have an ampacity of at least 125% of the total load to prevent overheating during extended operation. Luminaires used as raceways must meet specific requirements. 17 / 50 How should luminaires as raceways be identified (410.64)? a. They must be grounded with a separate conductor. b. They do not require identification. c. They must be listed and marked as suitable for use as raceways. d. Only LED luminaires qualify. Incorrect. Identification as raceways is mandatory for such luminaires. Correct! Luminaires must be marked as raceway compatible. Luminaires used as raceways must be listed and marked for this purpose to ensure compliance and safety. Proper disconnection ensures safe servicing. 18 / 50 What is required for the disconnecting means of fixed electric space heating equipment (424.19)? a. Only the branch-circuit breaker is necessary. b. It must simultaneously disconnect all ungrounded conductors and be lockable in the open position. c. Disconnecting means must always be within sight of the heater. d. No disconnecting means is required for small heaters. Incorrect. The disconnecting means must meet these specific requirements. Correct! Safety mandates simultaneous disconnection and lockability. The disconnecting means must disconnect all ungrounded conductors simultaneously and be capable of being locked in the open position to comply with safety requirements. Overcurrent protection is tailored to the appliance’s characteristics. 19 / 50 How must overcurrent protection for appliances be provided (422.11)? a. Using a standard circuit breaker regardless of the rating. b. Based on the appliance’s weight. c. Always with a fuse. d. In accordance with the appliance's marked rating or specific NEC provisions. Incorrect. Protection must match the appliance’s rating and NEC guidelines. Correct! Overcurrent protection is tailored to the appliance’s rating. Appliances must have overcurrent protection based on their marked rating or the applicable NEC requirements, ensuring proper protection. Wet locations require reduced voltage limits to enhance safety. 20 / 50 What is the maximum operating voltage for low-voltage lighting systems in wet locations (411.3)? a. 15 volts DC. b. 15 volts AC or 30 volts DC. c. 30 volts AC or 60 volts DC. d. No specific voltage limit applies. Incorrect. Wet locations have stricter voltage limits for safety. Correct! Wet location voltage is limited to 15 volts AC or 30 volts DC. Low-voltage lighting systems must not exceed 15 volts AC or 30 volts DC in wet locations to minimize shock risks. Proper wiring arrangement prevents damage and hazards. 21 / 50 How must wiring within luminaires be arranged (410.50)? a. Neatly arranged and not exposed to physical damage. b. Exposed for ventilation. c. Left loose for flexibility. d. Strapped to the luminaire housing. Incorrect. Wires must be neat and protected from damage. Correct! Wires must be neat and shielded from damage. NEC requires that wiring within luminaires be neatly arranged and protected from physical damage to ensure safety and durability. The scope includes a broad range of electrical appliances 22 / 50 What types of appliances are covered by Article 422 (422.1)? a. Only heating appliances. b. Appliances used exclusively in residential settings. c. Only appliances rated above 50 volts. d. All electrical appliances used in any occupancy. Incorrect. The scope includes more than just specific types of appliances. Correct! The article applies to all electrical appliances. Article 422 covers all electrical appliances used in any occupancy, regardless of type or application. Combustible material proximity can cause fire hazards. 23 / 50 What is required for recessed luminaires in combustible materials (410.116(A)(1))? a. No spacing requirements apply. b. Must have recessed parts spaced at least 1/2 inch from combustibles unless Type IC. c. Can touch combustibles if rated for 90°C. d. Must be spaced at least 1 inch. Incorrect. The spacing requirement is 1/2 inch unless Type IC. Correct! 1/2 inch spacing is mandatory for non-Type IC luminaires. Non-Type IC recessed luminaires must maintain at least 1/2 inch of clearance from combustibles, ensuring safe operation. Receptacle circuits must be independent of heating circuits. 24 / 50 What is required for electric baseboard heaters with factory-installed receptacles (424.10)? a. They must not be connected to the heater’s circuit. b. They can only be installed in bedrooms. c. They must be connected to the heater’s circuit. d. They require no special handling. Incorrect. Receptacles and heater circuits must be separate. Correct! Receptacles cannot connect to the heater’s circuit. Factory-installed receptacle outlets must not connect to the heater circuit, ensuring compliance with general electrical circuit requirements. The article applies to specific industrial equipment. 25 / 50 What type of equipment is covered under Article 425 (425.1)? a. Fixed industrial process heating equipment using resistance or electrode technology. b. Only electrode-type boilers. c. Portable space heaters. d. Residential heating systems. Incorrect. Article 425 is specific to industrial process heating equipment. Correct! This article covers industrial process heating using these technologies. Article 425 applies to fixed industrial process heating equipment employing electric resistance or electrode heating technologies, such as boilers, duct heaters, and immersion heaters. Disconnecting means must meet specific motor load standards. 26 / 50 What must disconnecting means for industrial control panels comply with (409.30)? a. Article 240. b. Part IX of Article 430 for motor loads. c. Only UL standards. d. No specific requirements. Incorrect. Article 430 Part IX governs disconnecting means for motor loads. Correct! Disconnecting means must comply with Article 430 Part IX. Disconnecting means for industrial control panels serving motor loads must comply with Part IX of Article 430, covering motor control requirements. Fault current ratings ensure panels can handle potential short-circuit conditions. 27 / 50 What is required for the short-circuit current rating of industrial control panels (409.22)? a. It can be calculated after installation. b. It must equal the service voltage. c. It must be marked and must not exceed the available fault current at the installation site. d. It is not required for panels with control circuits only. Incorrect. Marking and compliance with available fault current are mandatory. Correct! Marking and compliance with fault current limits are required. Industrial control panels must be marked with a short-circuit current rating and installed only where the available fault current does not exceed this rating, ensuring safety. Fiberboard’s combustible nature necessitates careful installation. 28 / 50 What is required for luminaires mounted on fiberboard (410.136(B))? a. No special requirements apply. b. Must use special screws for attachment. c. Must be installed with no air gap. d. Must be spaced 1.5 inches unless marked for fiberboard use. Incorrect. NEC requires specific spacing or markings for fiberboard installations. Correct! Proper spacing or markings are required for fiberboard installations. Surface-mounted luminaires on fiberboard must either be marked for this condition or spaced at least 1.5 inches from the surface. Equipment in damp locations needs special construction. 29 / 50 What is required for fixed industrial process heating equipment installed in damp locations (425.12(B))? a. Must be listed for damp locations and prevent water from entering wired sections. b. Must be raised at least 3 feet above the ground. c. Must be installed with standard enclosures. d. No specific requirements for damp locations. Incorrect. Damp location installations require specific listing and construction. Correct! Listing and water prevention are required for damp locations. Equipment installed in damp or wet locations must be listed for such conditions and designed to prevent water accumulation in wired sections. Continuous loads require specific ampacity adjustments. 30 / 50 How must branch circuits for fixed industrial process heating equipment be sized (425.4(B))? a. No specific sizing requirements. b. At 100% of the load. c. Based on the maximum rated voltage. d. At 125% of the total load as continuous loads. Incorrect. NEC requires branch circuits to account for continuous operation. Correct! Branch circuits must be sized for continuous loads at 125%. Branch circuits for fixed industrial process heating equipment must be sized at 125% of the total load, as they are considered continuous loads under NEC. NEC ensures replaceable elements are clearly identified. 31 / 50 What marking is required for replaceable heating elements rated over 1 ampere (422.61)? a. Only the appliance rating is required. b. Marking with voltage and manufacturer's logo only. c. No marking is required. d. Marking with voltage, amperage, or wattage. Incorrect. Marking with these ratings is required. Correct! Elements must be marked with voltage, amperage, or wattage. Replaceable heating elements rated over 1 ampere must be legibly marked with voltage, amperage, or wattage ratings to ensure proper replacement. Subdividing circuits limits short-circuit energy. 32 / 50 How must overcurrent protection for resistance-type heating elements exceeding 48 amperes be managed (424.22(B))? a. Subdivide the load into circuits not exceeding 48 amperes. b. No overcurrent protection is required. c. Use a single device rated for the total load. d. Protect at 60 amperes regardless of load. Incorrect. Loads must be subdivided and protected accordingly. Correct! Subdividing ensures safe operation for higher loads. Loads exceeding 48 amperes must be subdivided into circuits, each protected by a device rated at no more than 60 amperes, to reduce short-circuit risk. This article addresses a wide range of lighting devices and systems. 33 / 50 What is the scope of Article 410 (410.1)? a. Covers luminaires, lampholders, lamps, and related equipment for various lighting installations. b. Applies exclusively to decorative lighting. c. Covers residential lighting installations only. d. Includes only incandescent lamps. Incorrect. The article covers more than just one type of lighting installation. Correct! Article 410 applies to various lighting and related equipment. Article 410 encompasses luminaires, portable luminaires, lampholders, and related wiring and equipment, including decorative and seasonal lighting. Article 424 focuses on a specific category of heating equipment. 34 / 50 What does NEC Article 424 primarily cover (424.1)? a. All types of heating equipment, including process heating. b. Portable space heaters. c. Only central heating systems. d. Fixed electric equipment used for space heating. Incorrect. Article 424 only applies to fixed electric space-heating equipment. Correct! The article is about fixed electric space-heating equipment. Article 424 covers fixed electric equipment such as baseboard heaters, heating cables, and central heating systems used for space heating, excluding process heating and room air conditioning. The cord length must balance accessibility and safety. 35 / 50 What are the flexible cord length requirements for built-in dishwashers (422.16(B)(2))? a. 1 to 2 feet. b. 5 to 7 feet. c. No specific length requirements. d. 3 to 6.5 feet. Incorrect. The correct length range is 3 to 6.5 feet. Correct! The cord length must be between 3 and 6.5 feet. Flexible cords for built-in dishwashers must be between 3 and 6.5 feet to ensure proper installation and safe operation. Nameplates provide essential details for proper installation. 36 / 50 What marking must nameplates on fixed electric space-heating equipment include (424.28(A))? a. Voltage, wattage or amperage, and frequency. b. Installation date. c. No specific marking is required. d. Manufacturer's name only. Incorrect. Nameplates must display these specifications. Correct! Nameplates must include voltage, wattage/amperage, and frequency. Nameplates must include information such as voltage, wattage or amperage, and frequency to ensure the equipment is correctly installed and operated. Suspended ceiling systems require secure attachment to handle weight. 37 / 50 What is required for luminaires supported by suspended ceilings (410.36(B))? a. Must be lightweight luminaires only. b. Use of plastic supports is sufficient. c. Framing members must be securely fastened to the building structure. d. No specific requirements for attachment. Incorrect. Secure attachment is required for safety. Correct! Secure attachment of framing members is mandatory. Framing members in suspended ceilings must be securely attached to the building structure, ensuring proper support for luminaires. Safety and reliability are key considerations for equipment use. 38 / 50 Are reconditioned luminaires and related equipment allowed (410.2)? a. Yes, with proper certification. b. Yes, in non-critical areas. c. Only for temporary use. d. No, reconditioned luminaires, lampholders, and related components are not permitted. Incorrect. Reconditioned equipment is not allowed under NEC. Correct! Reconditioned luminaires and related equipment are prohibited. NEC prohibits the use of reconditioned luminaires, lampholders, and retrofit kits to ensure compliance and reliability. Overheating can lead to fire risks. 39 / 50 What is the purpose of thermal protection in recessed luminaires (410.115(B))? a. To regulate ambient room temperature. b. To cool the lamp for efficiency. c. To reduce glare. d. To prevent overheating of the luminaire and adjacent materials. Incorrect. Thermal protection is designed to prevent overheating. Correct! Thermal protection prevents luminaire overheating Thermal protection prevents overheating in recessed luminaires, protecting both the luminaire and surrounding materials. Nameplates provide essential appliance information for installation and maintenance. 40 / 50 What is required for nameplates on appliances (422.60)? a. Nameplates must only display the manufacturer's name. b. Visible or easily accessible nameplates with voltage, amperage, and wattage information. c. Marking with voltage and amperage only. d. No nameplate is required. Incorrect. Nameplates must provide detailed electrical specifications. Correct! Nameplates must include this essential information. Appliances must have visible or easily accessible nameplates showing voltage, amperage, and wattage ratings, ensuring compliance and easy reference. Covering outlet boxes is necessary for safety and aesthetics. 41 / 50 How must outlet boxes for luminaires be handled (410.22)? a. They can be left uncovered. b. They require a separate junction box. c. They must be covered by a luminaire canopy, faceplate, or similar device. d. They must use a non-metallic cover. Incorrect. Outlet boxes must be covered. Correct! Outlet boxes require proper coverage. Outlet boxes must be covered by a suitable canopy, faceplate, or similar device to protect wiring and ensure a finished look. Special environments require specific equipment labeling. 42 / 50 How must luminaires installed in commercial cooking hoods be identified (410.10(C)(1))? a. For use within commercial cooking hoods. b. As general-purpose luminaires. c. For outdoor use. d. No specific identification is required. Incorrect. These luminaires must be identified for use in cooking hoods. Correct! Identification ensures suitability for cooking hoods. Luminaires in commercial cooking hoods must be identified for this specific use to handle grease, heat, and vapors safely. Wet location luminaires require specific construction and marking. 43 / 50 How must luminaires in wet locations be installed (410.10(A))? a. With any type of enclosure. b. With no additional marking or requirements. c. So that water cannot enter wiring compartments, and marked suitable for wet locations. d. With damp location marking only. Incorrect. Wet location luminaires require appropriate markings and construction. Correct! Wet location installation requires specific markings and designs. Luminaires installed in wet locations must prevent water entry and must be marked as suitable for wet locations. Manufacturer specifications determine safe installation. 44 / 50 What spacing is required for heaters from combustible materials unless otherwise listed (424.13)? a. At least 1 inch. b. No spacing is required. c. Spacing as specified by the equipment listing. d. Only for heaters over 10 kW. Incorrect. Spacing depends on the equipment’s listing requirements. Correct! Follow spacing specifications provided by the listing. Heaters must maintain spacing from combustibles as specified by the equipment listing unless the equipment is designed for direct contact. Equipment in these locations must meet specific environmental ratings. 45 / 50 How must fixed space-heating equipment in damp or wet locations be rated (424.12(B))? a. Listed for damp or wet locations. b. Suitable for dry locations only. c. Installed at least 10 feet above the ground. d. No rating is necessary. Incorrect. Equipment must be listed for damp or wet locations. Correct! Only listed equipment is allowed in these environments. Fixed space-heating equipment in damp or wet locations must be listed for such conditions to ensure safety and functionality. Clearances ensure safe installation in storage spaces. 46 / 50 What is the minimum clearance for surface-mounted luminaires in clothes closets (410.16(D)(1))? a. 1 inch. b. 12 inches from the nearest point of storage space. c. 18 inches from the floor. d. No clearance is required. Incorrect. The minimum clearance is 12 inches. Correct! 12 inches is the minimum clearance required. Surface-mounted luminaires must maintain at least 12 inches of clearance from the nearest point of clothes closet storage space. NEC specifies a minimum voltage for mandatory listing. 47 / 50 What is the minimum voltage at which appliances must be listed (422.6)? a. 100 volts. b. No listing is required. c. 120 volts. d. 50 volts or higher. Incorrect. Appliances must be listed at 50 volts or higher. Correct! Appliances at 50 volts or higher require listing. Appliances operating at 50 volts or higher must be listed to ensure safety and compliance. NEC provides detailed grounding and bonding requirements for safety. 48 / 50 How must industrial control panels be grounded and bonded (409.60)? a. Grounded and bonded in accordance with NEC 250.122 and 250.102(D). b. No specific grounding or bonding is required. c. Only grounded through supply conductors. d. Only bonded, grounding is not required. Incorrect. Both grounding and bonding are mandatory per NEC requirements. Correct! NEC mandates grounding and bonding for control panels. Grounding conductors must meet NEC 250.122, and multisection panels must be bonded using jumpers sized per NEC 250.102(D). NEC specifies spacing or marking for installations near fiberboard. 49 / 50 How must luminaires near combustible low-density cellulose fibreboard be installed (410.136(B))? a. Flush with the fiberboard. b. Without additional measures. c. Spaced 1.5 inches or marked for this condition. d. Installed with a separate cover. Incorrect. Spacing or proper marking is required. Correct! Spacing or specific marking ensures safe installation. Luminaires near combustible low-density cellulose fiberboard must be spaced 1.5 inches unless marked for installation directly on fiberboard. Safety and manual operation are key for disconnecting means. 50 / 50 How must thermostatically controlled switching devices be designed if used as disconnecting means (424.20(A))? a. They must disconnect all ungrounded conductors and have a marked "off" position. b. They can rely on remote control for operation. c. They must disconnect all grounded conductors. d. They do not require manual controls. Incorrect. These devices must manually disconnect all ungrounded conductors. Correct! Manual disconnection and clear markings are required. Thermostatically controlled switching devices must manually disconnect all ungrounded conductors and feature a clearly marked “off” position for compliance. Your score is LinkedIn Facebook Twitter 0% Restart quiz Exit Rate & Review Thank you for taking the time to leave us a review! Your feedback is greatly appreciated and helps us improve our services. Send feedback Leave a Reply Cancel replyYour email address will not be published. Required fields are marked * Comment* Name* Email* Website Save my name, email, and website in this browser for the next time I comment. Post Comment