New York City DOB Master Electrician Practice Exam

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• What is the required resistance value in M ohms to discharge a 30 Mfd capacitor energized to 650V?
• How many 20A branch circuits are required for 80 linear feet of show window lighting space?
• For switchboards that are not totally enclosed, what is the minimum space required between the top of the switchboard and any combustible ceiling?
• Where can the connection of the system bonding jumper for a separately derived system be made?
• What is the maximum height for storing the coupling means of electric vehicle supply equipment at outdoor charging sites?
• How far below grade must underground service conductors be buried to require a warning ribbon?
• When is it permissible to use track lighting with receptacles in public bathrooms?
• What is the minimum wire gauge required for residential lighting circuits?
• What is the minimum thickness for a transformer vault floor made with bricks?
• What is the minimum ampacity rating required for a duplex receptacle in an elevator hoistway pit?
• According to electrical installation practices, what type of conduit should not be used for permanent exterior installations?
• What is the minimum number of duplex receptacles required for each patient bed in the critical care area of a hospital?
• Which method is NOT used to guard bare live parts from public access according to the NEC?
• For ampacity, what percentage of the full-load amperes listed on the phase converter nameplate should the single-phase supply conductors be rated at?
• What type of flexible cable is allowed for use in electric vehicle charging stations rated at 300 Volts?
• What is critical when designing electrical systems in healthcare facilities that involve anesthetics?
• What is the maximum ampacity requirement for feeder conductor installations?
• What is considered a safe working distance for electrical maintenance near live parts?
• What is required for ENT and fitting encased in poured concrete?
• What is the requirement for the lighting in the elevator hoistway pit?
• What happens if the voltage drop exceeds the maximum allowable percentage for a dwelling unit?
• How many receptacles are required on a balcony, deck, or porch with a usable area of less than 20 square feet?
• A fixed storage type water heater of 120 gallons or less shall be considered a continuous load, with branch circuit conductors having an ampacity of what percentage of the nameplate current rating?
• What is the purpose of audible and visual signal devices in an emergency system?
• What type of cable assembly is most appropriate for outdoor lighting applications?
• What is the minimum rating for a duplex receptacle located in an elevator hoistway pit?
• How much profit does an electrician make when he sells 100 units of armored cable connectors bought for $2.10 each at a selling price of $3.00 each, with 30% overhead?
• What does the term "branch circuit" refer to in electrical installations?
• What is not required to be marked on signaling wire cable?
• How is voltage defined in the code?
• For a service switchboard rated over 5000A, what is the ampacity requirement for copper bus bars?
• What does inverse time indicate in circuit breaker operation?
• For fixtures located close to a ballast, what is the minimum temperature rating required for conductors?
• What does the term "patient care area" refer to in a healthcare facility?
• Which appliance is permitted to have a 24" cord with attachment ground plug?
• What is the kVA requirement for a dishwasher in a multi-family building?
• If it takes 2.6 hours to install outlets in each room, how many rooms can be completed in 5 days with men working 8 hours a day?
• For fixed in-place X-ray equipment, what is the maximum amperage that should supply the device?
• What is the maximum allowable total voltage drop on branch-circuit conductors?
• Which device must not be connected to the lighting circuit in the elevator hoistway pit?
• What is the minimum width of an entrance to electrical enclosures for equipment over 600V nominal?
• What is a limited care facility defined as in terms of housing capability?
• What ambient temperature increase should be applied for conduits exposed to direct sunlight on rooftops?
• When referring to snap switches rated at 30 Amps, what should their over-current protection not exceed?
• In what scenarios can an existing cartridge fuse be replaced according to regulations?
• Class 2 and Class 3 circuits must be separated from Class 1 conductors by what type of barrier?
• What is the required working space for access to live parts operating at 300V to ground?
• Cartridge fuses of the renewable type are allowed for replacement only in existing installations if which condition is met?
• What is the minimum clearance required for a 22KV overhead line in areas subjected to truck traffic?
• In healthcare settings, how should the electrical fittings be designed when installed for electronic equipment?
• Where should Type 3 surge protective devices be installed?
• Knife switches rated for more than 1200A at 250V or less are restricted to which usage?
• What is the minimum distance for a nonmetallic sheath cable to enter the top of a surface-mounted enclosure through raceways?
• What is the minimum requirement for coverings over equipment in hazardous locations?
• In anesthetic areas, what is the maximum voltage allowed for equipment frequently in contact with bodies?
• What type of load can resistive and inductive alternating-current general-use snap switches control?
• When an internal combustion engine is used for the emergency system, how long should the onsite fuel supply last?
• Under what condition are fuses and circuit breakers permitted to be connected in parallel?
• What type of protection must be provided for equipment operating above 600V in patient care areas to ensure safety?
• What is the minimum bending radius for type AC cable?
• What is the requirement for terminating metal raceways?
• What is a common use for armored cable connectors in electrical installations?
• Which type of area in healthcare facilities is NOT considered a patient care area?
• What is the required clearance in front of switchboards installed facing each other?
• What is the minimum clearance required for service conductors installed as unjacketed multi-conductor cable from windows that can be opened?
• What is the average weight of a manhole cover designed to deter unqualified persons from accessing the opening?
• For what condition must conductors' locations be identified with a warning ribbon?
• Type S fuse adapters are designed so that they cannot be removed once inserted into what?
• What is the maximum run length of an 18AWG fixture wire tapped onto a 20A branch circuit?
• How many 20A small appliance branch circuits are needed in a dwelling unit kitchen?
• Ground-fault protection of equipment is required from solidly grounded electrical services exceeding what voltage?
• Where can electrical noise be reduced for electronic equipment?
• What is the maximum over-current protection for infrared lamps used in commercial and industrial heating appliances?
• What rating should branch circuit conductors have if they are within 3 inches of a ballast?
• In a health care facility, receptacles used in a hazardous location within an anesthetizing area must be listed for which class and group?
• For pull boxes, which of the following conditions applies when using cables entering the box?
• In the context of a multi-family building, what is the power rating of the range mentioned?
• In patient care areas, what surfaces of fixed electric equipment operating at over 600V must be grounded?
• What is the minimum space required between the top of a switchboard and any combustible ceiling if the switchboard is not fully enclosed?
• What is the required minimum separation between supply service drops running above and parallel to communication service drops at any point in the span?
• How must grounded conductors be identified when they are #6 AWG or smaller?
• Which phrase indicates a mandatory requirement in NEC terminology?
• When connecting a surge protective device, what should be avoided?
• How far can an outlet for specific appliances, such as laundry equipment, be located from the appliance in a dwelling unit?
• What fuse size is required for a 100 HP DC motor at 220V with 90% efficiency?
• Which flexible cable is permitted for use in Electric Vehicle Charging Stations?
• What is the maximum allowed distance between receptacles in a residential hallway?
• What is the main purpose of ground-fault protection in electrical installations?
• According to New York City NEC, how many branch circuits are required for air conditioner receptacles in a dwelling unit?
• What type of lights are permitted to be installed in ducts or plenums used for environmental air?
• To which group do receptacles and attachment plugs in anesthetizing areas need to be listed for use?
• What is the minimum load requirement for household electric clothes dryers in a dwelling unit?
• What is the power rating of the water heater mentioned for the multi-family building?
• In terms of current, what does the term 'magnitude' refer to?
• What is the correct size for a grounding conductor in standard installations?
• What is the minimum overhead clearance for service drop conductors over residential property and driveways not subject to truck traffic where the voltage does not exceed 300V?
• What is required for the grounding of central vacuum outlet's accessible non-current carrying metal parts?
• What is the minimum clearance required for unjacketed multiconductor cable installed as service conductors near windows, doors, and similar locations?
• What is the total power requirement for the dryer in the multi-family building?
• In a straight pull, what is the minimum length of the box compared to the trade size of the largest raceway?
• What is the insulation temperature rating required for conductors close to a ballast?
• What is the demand factor for marina load calculations of 45 shore power receptacles?
• In which scenario is the installation of a Type 1 TVSS considered appropriate?
• What is the permitted load demand factor for four or more appliances that are fastened in place?
• What is the maximum insulation temperature rating for feeder and branch circuit conductors within 3 inches of a ballast?
• What is the method for ensuring conductors are not damaged during bending?
• How many receptacles must each general care area or patient bed location have?
• What characteristic is critical for supporting electrical conductors?
• What is the limitation for knife switches rated for over 1200 amps at 250 volts or less?
• Where should the grounding of communication wires be run?
• Under which condition can Class 2 and Class 3 circuits be placed with Class 1 or electric light or power conductors?
• What is the maximum distance that branch circuit conductors can be from the ballast while maintaining a certain insulation temperature rating?
• How are plug fuses rated at 15 amperes and lower identified?
• What is the primary purpose of the mandatory rules outlined in electrical codes?
• What factors must emergency circuit wiring minimize the risk of failure due to?
• What is the minimum required separation between network communication cables and power cables?
• What is the minimum access opening size for a manhole?
• At what height must electric vehicle supply equipment be located in indoor settings?
• How many duplex receptacles must be provided for each patient bed in critical care areas?
• AC or DC general use snap switches can control inductive loads not exceeding what percentage of the ampere rating of the switch?
• What is the minimum ampacity requirement for supply branch circuit conductors for x-ray equipment?
• What is the minimum headroom required for working spaces around a motor control center?
• What is the function of a feeder circuit in the context of receptacles?
• What is the maximum extension allowed for electrical equipment within a working space?
• What is the minimum horizontal climbing space provided by conductors on poles, where power conductors are below communication conductors?
• Which type of damage must electrical equipment enclosures be protected from?
• What is the voltage requirement for the electric vehicle supply equipment to function properly indoors?
• Over a hot tub protected by GFCI, what is the required mounting height for light fixtures supported by EMT in NYC?
• What type of protections are required for enclosures that house electrical equipment at risk of physical harm?
• What is the minimum clearance height required for overhead feeder conductors over commercial areas with truck traffic?
• In what situation is a wall, screen, or fence recommended for enclosing an outdoor electrical installation?
• Which electrical system includes a backup for critical care in healthcare environments?
• When is GFCI protection not required for equipment at a carnival?
• What is not typically listed on a motor disconnect switch?
• Mandatory rules of the code are characterized by which terms?
• What must low-voltage equipment in anesthetizing areas be approved as?
• Type 3 Surge Protective Devices must meet which requirement regarding their connection from the distance to service disconnect?
• What should be the minimum clearance from the floor to any energized part of a switchboard?
• Which type of conduit is acceptable for use with Type SE cable in New York City?
• What is the maximum length of flexible metal conduit allowed in ducts or plenums for environmental air?
• When a power-operated switch or circuit breaker is used as a service disconnecting means, what must it be capable of during a power supply failure?
• What is the minimum cross-sectional area required for the internal bonding bus of a multisection switchboard?
• In terms of electrical installations, what does "working space" refer to?
• What is the minimum size for service lateral conductors supplying power to limited loads in a single branch circuit?
• Which cable type can be used for services not rated over 600 volts when enclosed in a threaded metallic conduit in New York City?
• What is a knife switch rated for more than 1200 Amps at 250 Volts or less allowed to be used as?
• How many receptacles must each general care area patient bed location be provided with at a minimum?
• What is the required door swing direction for personnel exiting a workspace that is less than 25 feet from the working space?
• What type of installations is Type CL3 cable suitable for?
• What is the minimum rating for safety disconnects serving hermetic refrigeration equipment?
• When reducing electrical noise for electronic equipment, which fitting is acceptable to use?
• Which type of medical x-ray equipment does not require an individual branch circuit?
• What two systems comprise the essential electrical system in a healthcare facility?
• The minimum required distance for overhead power lines above a public area is typically _____ feet?
• What should be used for protection and support of single insulated conductors?
• What is the maximum distance a 15A or 20A 125V receptacle outlet should be located from heating, air conditioning, and refrigeration equipment?
• What is the minimum grounding conductor size for communication circuits?
• What is required above underground electrical installations buried less than 30 inches?
• Why is track lighting with outlets in a bathroom not allowed?
• For guest rooms in hotels and motels, what is the requirement for receptacle outlets in comparison to dwelling units?
• What is the required separation distance for open conductors installed outside?
• What is the interrupting capacity of a class H fuse?
• What is the minimum insulation temperature rating required for branch circuit conductors near a ballast?
• Under what condition can a receptacle outlet in the floor be counted towards the required number of receptacle outlets?
• For straight pulls, what is the minimum length of a pull box for cables over 600V?
• In a dwelling unit, what percentage of change in circuits running through another dwelling unit requires that it be up to code?
• What must be marked on equipment installed in hazardous locations?
• Which factor is critical when selecting branch circuits for fixed equipment?
• What is the maximum allowable time for emergency lighting or power to be available during an emergency?
• In the context of building codes, what term is used to identify mandatory rules that are required or prohibited?
• What is the minimum required separation distance between communication wires and cables and building conductors?
• What is the minimum radius of a field bend on trade size 1 1/4 RMC?
• For equipment rated at 1200A or more, what is the required entrance and egress dimension for working space?
• What is the required ampacity for branch circuit conductors supplying a single motor in continuous duty?
• What is the power rating for the heat in the multi-family building?
• What is the short circuit capacity of a 72 KVA transformer with a 240V secondary and 3% impedance?
• What is the height requirement for the coupling means of electric vehicle supply equipment?
• What is the main function of patient care areas in healthcare facilities?
• What type of fitting may the metal raceway terminate to when installed to reduce electrical noise?
• How frequently must manufactured wiring systems constructed with type MC cable be supported and secured?
• What type of electrical supply is necessary for patient care and basic hospital operations?
• What is the minimum on-premise fuel supply required for internal combustion engines used as prime motors?
• What is the load requirement for an electric clothes dryer in a dwelling unit?
• What is the main limitation of knife switches rated above 1200 amp?
• What percentage of full charge must a storage battery maintain for emergency lighting and power?
• What is essential to ensure in an electrical installation testing stage?
• In which type of facility must receptacles and attachment plugs in hazardous locations be specifically listed for their intended use?
• When electrical equipment is exposed to specific conditions, what must be ensured regarding enclosure guards?
• What is the minimum dimension of working space required for access to live parts operating at 300V?
• How should Type S fuse adapters be designed in relation to their fuse holders?
• Where should unit equipment (battery packs) be connected?
• What must be done with the equipment grounding terminal buses serving the same patient care vicinity?
• What is the correct term for the first disconnecting means on a separate derived system?
• What is the minimum number of branch circuits required for patient bed locations in critical care areas?
• For phase converters serving variable loads, what is the minimum ampacity for the single-phase supply conductors?
• What minimum clearance is required in front of a switchboard installed in one line?
• What does the enclosure or guards for electrical equipment exposed to physical damage need to be?
• How many transfer switches can branch circuits for patient bed receptacles originate from in emergency systems?
• What type of care is a hospital designed to provide on a 24-hour basis?
• How many amperes does a typical 20A branch circuit carry?
• What is the total resistance of a circuit comprising two 8MFD capacitors connected in series at 60HZ?
• What type of cable is identified for use as underground service entrance cable?
• How far must open conductors installed outside be separated from open conductors of other circuits or systems?
• What is the purpose of ground-fault protection for equipment in electrical services rated over 150V?
• Which type of cable is identified for use as underground service-entrance cable?
• In healthcare facilities, what must each patient bed location accommodation include?
• For junction boxes, what is the minimum required depth for installation?
• How far shall lighting systems operating at 30V or less be installed from pools, spas, and similar locations?
• What is the requirement for the grounding of central vacuum outlet assemblies?
• What should the dimensions of the room housing a switchboard provide?
• What type of ladder must be provided when manhole openings cannot be placed safely?
• What is the minimum distance allowed between angle or U pulls and the opposite wall of the box?
• On a 4 wire delta connected phase system with a grounded midpoint, how must the conductor with the higher phase voltage be marked?
• What is the required insulation temperature rating for branch circuit conductors near a ballast?
• What identification must be visible on a main bonding jumper that uses a screw?
• What is the minimum size for a grounding conductor when using copper?
• What is the height requirement for working space entry for equipment that is over 6 feet wide?
• What is the minimum width of working space required in front of electric equipment?
• Where should the ferromagnetic envelope be bonded when skin effect exists?
• What is the minimum height requirement for the coupling means of electric vehicle supply equipment?
• How many 20A branch circuits are required for laundry outlets in a dwelling unit?
• Where should manhole openings for personnel not be located?
• Which of the following is not considered a power supply?
• What is the minimum height above floor or working surface for equipment located in restricted access areas for qualified persons?
• How many receptacles are required on a balcony, deck, or porch with a usable area of less than 20 square feet?
• The maximum power supply rating for a lighting system under Article 411 is _____ amps?
• Fixed in place X-ray equipment should be supplied by a branch circuit rated at no more than what amperage?
• What is required for the room housing switchboards totaling 1000KV or larger?
• What is the primary concern of placing dry type transformers in a vault?
• When located outdoors, what is the minimum height for electric vehicle supply equipment?
• What is defined as an individual branch circuit?
• What standard helps to determine the workspace required around electrical equipment?
• What type of conductors must not be used closer than 10 feet to water features?
• What is the maximum allowable voltage drop from the service point to the last over-current device in a dwelling unit?
• Who is responsible for conducting or witnessing an acceptance test of the complete emergency system?
• How many #10 conductors can be legally installed in a 4-inch square box that is 2-1/8 inches deep?
• What is the minimum cover requirement for rigid metal conduit that is directly buried outdoors?
• What is the minimum distance for wall-mounted luminaries below the surface of water in a pool?
• What is the minimum size of overhead service drop conductors in copper?
• What is the recommended height for a fence enclosing outdoor electrical installations to deter access by unqualified individuals?
• What is the acceptable temperature rating for electrical conductors in commercial installations?
• What is the minimum size of wires that must be used for limited loads on single branch circuits?
• What is the minimum wire size for an equipotential plane connected to the electrical grounding system in an agricultural building?
• In wiring installations, what does RMS stand for?
• What is the required fire rating for a room housing service equipment totaling 1000KVA or larger?
• Which organization is responsible for interpreting rules and approving equipment within the electrical code?
• What is the diameter of a #14 AWG wire?
• What happens if a specific requirement in the electrical code is waived?
• In terms of wiring practices, what should be done with conductors connected to surge protective devices?
• What is the requirement for ground-fault protection for alternate sources in emergency systems?
• Under what condition may service switches be installed on the outside of a building?
• Where should dry-type transformers rated over 35kV be installed when indoors?
• How should wiring from an emergency source to emergency loads be handled?
• What types of loads are alternating current general-use snap switches permitted to control?
• What is the function of the panel boards supplied by a three-phase, delta-connected system?
• For electronic equipment, what configuration is used to identify lower-rated fuses?
• How should other neutrals be marked if one is conventional white or natural gray?
• For non-dwelling occupancies, banks, or office buildings, what is the minimum calculation for each receptacle outlet?
• How should automatic transfer switches be operated and held?
• For cord and plug connected electric vehicle supply equipment, where should the interrupting devices of a personnel protection system be located?
• To what type of circuit must the sump pump and lights in the elevator pit be connected?
• Who is authorized to access the feeder and branch circuit overcurrent devices?
• Which of the following is not part of the classification of an incandescent lamp?
• What is the proper method for calculating demand loads in marina applications?
• What is the purpose of the manufacturer’s instructions for Type 3 SPDs?
• In a residential setting, what is the recommended grounding method for metal water piping?
• Which type of cables are classified as suitable for general purpose use with the exception of certain environmental air spaces?
• Where can a Type 1 TVSS installation be connected?
• In healthcare facilities, how many branch circuits are required for patient bed receptacles located in general care areas?
• Which of the following should not be connected to the life safety branch in a hospital?
• How many duplex receptacles must be provided at each general care area patient bed location in a healthcare facility?
• How should an insulated grounded conductor of #6 AWG or smaller be identified?
• In which hazardous locations are flammable anesthetics employed as classified?
• Transfer equipment, including automatic transfer switches, must be identified for what purpose?
• What type of materials must be used for constructing the room where service equipment of 1000KVA or larger is installed?
• How much separation must power conductors on poles have from communication conductors when the power is greater than 300V?
• What is the total calculated load in VA for a waste disposal, dishwasher, trash compactor, and water heater?
• When the code says "Shall be permitted," what does it mean?
• What is the ampacity requirement for a continuous load from a storage type water heater?
• What is the minimum number of patients for a building to qualify as a hospital?
• In healthcare facilities, what must the placement of receptacles in anesthetic areas ensure?
• How long must a box be in a straight pull relative to the size of the largest raceway?
• Which of the following may emergency circuit wiring enter along with normal circuit wiring?
• What color should the neutral conductor have when different systems are installed in the same raceway?
• For an electric clothes dryer, which rating should be used if the nameplate rating is higher than the standard load?
• At what voltage level must exposed live parts of motors and controllers be guarded against accidental contact?
• What is a key grounding requirement for central vacuum outlet assemblies?
• What is the minimum clearance required between two services at the pole for parallel service drops?
• How many receptacle outlets are permitted on a 20A, 120V circuit in a commercial building?
• What is the minimum vertical clearance required for overhead feeder conductors over residential property and driveways with a voltage limited to 300V to-ground?
• What is the minimum feeder load for show window lighting per linear foot?
• Service conductors must maintain clearance specifically from which of the following?
• What is the significance of a space less than 1/2 inch from the rooftop in conduit installations?
• What is the main requirement for bonding ferromagnetic envelopes?
• Panel boards equipped with snap switches rated at 30 Amps or less must have over-current protection not exceeding what rating?
• What electrical potential must low-voltage equipment operate at in anesthetic areas?
• What is the maximum overcurrent protection allowable for #12 THHN or THWN wire when used for general wiring?
• In a multi-family building with 12 units, what is the total system voltage typically used?
• When installing flat top underfloor raceways, what must be the minimum spacing between raceways?
• What is the minimum distance receptacles must be set back from the inside wall around a pool?
• What is the minimum radius of a field bend on trade size 1 1/4 RMC?
• In what scenario would MV (multi voltage) cable not be suitable for installation?
• How far can associated equipment extend from the front of the electrical equipment within the working space?
• Which of the following methods is not permitted for the protection of equipment in electrical vaults?
• What is the minimum distance of service drops above the roof’s surface?
• What is the required concrete coverage depth for flat top underfloor raceways between 4 and 8 inches wide?
• What is a requirement for receptacles at general care area patient beds?
• What is the configuration for the phase with higher voltage in a three-phase, 4-wire, delta-connected system?
• Service drops installed over a roof must have a vertical clearance of what minimum height above the roof surface?
• What color or markings must an insulated grounded conductor of 6AWG or smaller have?
• What is the required vertical clearance above the roof surface for service drops?
• How many switches are required to control one light fixture from five different locations?
• What is open wiring on insulator?
• Which of the following is NOT a requirement for lighting systems operating under Article 411?
• What is the color code for the marking of the conductor with higher phase voltage to ground in a 4 wire delta connection?
• What is the minimum separation distance required between communication wires and lighting conductors?
• What is the primary purpose of the equipment grounding conductor in electrical systems?
• What is the minimum gauge for grounding conductors in communication circuits?
• What type of resistance must low-voltage equipment have in anesthetic areas?
• Which type of raceway is suitable for hinges on a movable ramp of a boathouse due to changing tides?
• When boring holes in wood members for cable installation, the edge of the hole must be at least how far from the nearest edge of the wood member?
• What is the required outlet configuration in relation to the wall for a floor receptacle?
• What is the appropriate amperage for fixed in-place X-ray equipment supplied through an attachment plug cap?
• Which appliance is permitted to have a 24-inch cord with an attachment ground plug?
• What is the minimum height at which a lighting truss can be installed above the finished floor?
• What is the minimum ampere rating for a disconnecting means that serves a hermetic refrigerant motor compressor?
• Which equipment does not require special measurement approval when outdoors?
• What is the maximum horsepower rating for a portable motor that allows its controller to be an attachment plug and receptacle?
• When three resistors are connected in series and produce an amperage of ten amps, what will the amperage be if an equal resistor is added in parallel with the existing three?
• What is the maximum internal current permitted through a line isolated monitor when grounded?
• What type of lighting is primarily used in show windows to improve product visibility?
• What is the minimum vertical clearance required for communication wires and cables from all points of the roof above which they pass?