What type of lamp holders required in a branch circuit has the rating of 20 amp or more?
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Most of the ac voltmeter and ammeters are calibrated to read in _____ values
Fuel Oil is defined as Kerosene or any hydrocarbon oil having a flash point not less than ____
Ducts that operate at temperatures exceeding ______ shall have sufficient thermal insulation to limit the exposed surface temperature
What is the low voltage contact limit for sinusoidal AC?
What is the delay time permitted to start emergency generators in-case of normal power supply failure?
Where ducts used for cooling are externally insulated, the insulation shall be covered with a vapor retarder having a maximum permeance of ______ perm
If a 30 amperes snap switch is used as disconnecting means of a 3-horse power motor, what shall be the maximum full load current of the motor?
If a single phase motor full load current is 30 Amperes, what is the dual element fuze size to be used as motor branch circuit short circuit protection?
_____ is the Refrigerants removed from a system in any condition without necessarily testing or processing them
The outline lighting system shall be at least _______ feet above the areas accessible to vehicles unless protected from physical damage.
The minimum openable area to the outdoors shall be ____ of the floor area being naturally ventilated
The vent horizontal termination point for a mechanical draft system shall not be located closer than _____ to an interior corner formed by two walls perpendicular to each other.
Fire dampers are not required at penetrations of shafts where the steel exhaust subducts extend at least _______ vertically in exhaust shafts provided that there is a continuous airflow upward to the outdoors
Cloth dryer Exhaust ducts shall be supported at _____ intervals and secured in place
Commercial cloth dryer ducts shall have a minimum clearance of _____ to combustible materials
Supply air to a swimming pool and associated deck areas shall not be recirculated unless such air is dehumidified to maintain the relative humidity of the area at _____ or less
Which flammable liquid having a flash point below 73°F (23°C) and a boiling point below 100°F (38°C)
An ohm meter connected across a 120 volts electrical heater shows 7.5 ohms, how much current the heater draws?
What is the demand factor applied in calculating feeder or service conductor load for a commercial kitchen having four electrical equipment
Gas appliances listed and labeled for venting with _____ vents
A disconnecting means of motors over 600 volts muse be capable of being locked in _______ so that it cannot be inadvertently closed when someone is working on the motor.
Flexible cards may not be used in the following locations _______
What is the minimum size of 3 wire service for single dwelling with an initial load of 20 kVA or more.
Equipment grounded conductors are identified by _______ color.
The full load current of 3 phase 4 HP continuous duty motor is 60ampers with service factor of 1.1. what is its rating of overload separator?
If a 230 volts load is connected to 240 volts power source, what is the minimum voltage that can be supplied to load as recommended by NEC?
PVC conduit shall be permitted to use in underground wiring where it is buried under not less than _______ of cover
How much maximum percentage of auxiliary gutters interior cross sectional area can be filled with conductors?
Underground Ducts shall have a minimum slope of _______ per foot to allow drainage to a point provided with access