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What is the minimum length of hallways in dwelling units that require at least one receptacle outlet?
Which of the following locations requires a receptacle outlet based on its linear width?
What is the minimum ampacity that feeders with a service carrying a load of 55 amperes or less must have?
How should fractions of an ampere less than 0.5 be treated in calculations?
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What is the minimum calculation for heavy-duty lampholders in terms of VA?
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According to load calculations, how much VA is assigned for track lighting per 600 mm?
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For what purpose must feeders for systems with common neutral be designed?
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What is the VA calculation for signage and outline lighting as per the requirements?
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What is the demand factor for the first 3000 VA in dwelling units?
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If a hospital has a lighting load of 60,000 VA, what demand factor should be applied to the remainder over 50,000 VA?
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What is the demand factor for hotels and motels with a lighting load between 20,001 VA and 100,000 VA?
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How much additional load should be included for every 600 mm of track lighting?
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What is the minimum load value for a show window per linear meter?
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For a dwelling unit dryer, which load value should be used if the nameplate rating is 4500 VA?
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What is the demand factor for the portion of lighting load in warehouses exceeding 12,500 VA?
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For lighting loads in all other categories, what is the demand factor applied?
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What marking should circuit breakers used as switches in fluorescent lighting circuits have?
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Which of the following is required for three-phase circuit breakers used for overcurrent protection?
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What is the purpose of an effective ground-fault current path?
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What defines a ground fault?
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Which component facilitates the operation of overcurrent protective devices in high-impedance grounded systems?
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What does a grounding electrode conductor do?
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What is the main goal of electrical system grounding?
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Which of the following is NOT a general requirement for grounding and bonding?
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What is essential for an effective ground-fault current path when bonding electrical equipment?
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Which materials are NOT acceptable for bonding connections?
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Which of the following systems is permitted to use a grounding electrode conductor NOT smaller than 80 mm2 for copper?
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What should be done to non-conductive coatings before making electrical connections?
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What is the minimum length of a metal underground water pipe to qualify as a grounding electrode?
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Which of the following circuits is NOT recommended to be grounded?
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Which bonding connection method is acceptable for electrical equipment?
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What characteristic defines an effective ground-fault current path?
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What is the maximum ampacity for Aluminum conductors rated over 200 through 325?
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Which scenarios require exposed non-current carrying metal parts to be grounded?
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What is the grounding requirement for equipment supplied by a metal-clad raceway?
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For which of the following types of equipment is grounding specifically required?
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What is the ampacity rating for Copper-Clad Aluminum conductors up to 50?
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Which condition is NOT a criterion for grounding exposed metal parts?
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Which of the following does NOT require grounding for their frames?
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What is the ampacity rating for Copper conductors that are rated over 400 through 850?
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Study Notes
Hallways and Receptacle Outlets
- Hallways in dwellings 3000 mm or more in length require at least one receptacle outlet.
- Show windows need one receptacle for each 3600 mm of linear width, installed directly above.
- Individual outlets for heating, air-conditioning, and refrigeration equipment must be at the same level as the equipment, within 7600 mm.
Required Lighting Outlets
- Lighting outlets are mandatory in habitable rooms, hallways, and stairways.
- Attached and detached garages with electric power also require lighting outlets.
- Interior stairways with six or more risers necessitate lighting outlets.
- Lighting is needed in storage spaces, equipment spaces, and guest rooms or suites.
Feeders: Minimum Rating and Size
- Feeders must have an allowable ampacity of noncontinuous load plus 125% of continuous load.
- For systems with 600 volts or less, feeders’ ampacity should be equal to or greater than that of the service and support loads of 55 amperes or less.
Branch Circuit, Feeder, and Service Calculations
- Voltages for calculations include nominal voltages such as 115V, 230V, 600V, etc.
- An ampere under 0.5 can be ignored in calculations.
- Heavy-duty lampholders have a minimum outlet calculation of 600VA.
- Sign and outline lighting outlets calculated at 1200VA.
- Show windows calculated at 200VA per 300 mm.
- Track lighting adds 150VA for every 600 mm.
- Receptacle loads in banks and office buildings calculated at 28VA/m².
Lighting Load Demand Factors
- Demand factors vary according to occupancy, influencing the lighting load calculation.
- For Dwelling Units: First 3000VA at 100% factor, 3001 to 120,000VA at 35%, over 120,000VA at 25%.
- Hospitals have reduced demand factors beyond 50,000VA (20%).
- Warehouses have strict load calculations for under and over 12,500VA.
Electric Clothes Dryers
- Each dryer in a dwelling must have a load of at least 5000 watts or its nameplate rating.
Overcurrent Protection
- Circuit breakers for overcurrent protection in three-phase circuits must include a minimum of three relay elements.
- Fuses connect in series with each ungrounded conductor.
Grounding and Bonding Requirements
- An effective ground-fault current path is mandatory for safety, ensuring fault current travels back to the source.
- Grounding of electrical systems and equipment limits voltage from lightning or contact with high-voltage sources.
- Bonding connects non-current carrying conductive materials to create an effective path for ground fault currents.
- Connections must be done using secure methods such as welding or tested clamps; soldered connections are not allowed.
Grounding Electrodes
- Permitted grounding electrodes include metal underground water pipes and metal frames of buildings.
- Common grounding electrode conductors need to be appropriately sized based on the type of metal.
Equipment Grounding Conductors
- Non-current carrying metal parts of fixed equipment must be grounded if within specified distances to the ground or other grounded objects.
- Equipment such as switchboard frames, motor frames, and various types of electrical equipment must maintain effective grounding.
Exemptions from Grounding
- Certain circuits, like those for electric cranes over combustible materials and in healthcare facilities, are not grounded for safety reasons.
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Description
This quiz focuses on the essential electrical standards regarding receptacle outlets in hallways and mandatory lighting outlets in various spaces. It also covers the specifications for feeders regarding their minimum ratings and sizes. Test your knowledge of these crucial electrical guidelines!
