PEC CHAPTER 2 WIRING AND PROTECTION Flashcards
USE AND IDENTIFICATION OF GROUNDED CONDUCTORS
Means of Identifying Grounded Conductors
a) Sizes 14 mm2 or Smaller
Continuous white or gray outer finish.
Three continuous white stripes on other than green insulation along its entire length.
USE AND IDENTIFICATION OF GROUNDED CONDUCTORS
Means of Identifying Grounded Conductors
b) Sizes Larger Than 14 mm2
Continuous white or gray outer finish.
Three continuous white stripes along its entire length other than green insulation.
At the time of installation, distinctive white or gray marking at its termination.
USE AND IDENTIFICATION OF GROUNDED CONDUCTORS
Means of Identifying Grounded Conductors
c) Flexible Cords
Shall be identified by a white or gray outer finish.
USE AND IDENTIFICATION OF GROUNDED CONDUCTORS
Means of Identifying Grounded Conductors
d) Grounded Conductors of Different Systems
Shall have the grounded conductors for different systems distinguishable, one having white outer finish and the other a gray outer finish, other than green.
BRANCH CIRCUITS
Rating In General - The rating for other than individual branch circuits shall be (5)
15, 20, 30, 40, and 50A.
BRANCH CIRCUITS
Rating over______A shall be permitted to supply non- lighting outlet loads.
50 Amperes
BRANCH CIRCUITS
Ground Fault Circuit Interrupter Protection
a) Dwelling Units - All 125/250 volts, single phase, 15-20 amperes receptacles installed in the following locations shall be of GFCI protection:
- Bathrooms
- Garages, and also accessory buildings that have a floor located below grade level
- Outdoors
- Crawl spaces - at or below grade level
- Unfinished basements (not habitable rooms such as storage areas, work areas)
- Kitchen (receptacles on countertops)
- Laundry circuits, and wet bar sinks (receptacles within 1800 mm from the edge of sink)
- Boathouses
BRANCH CIRCUITS
Ground Fault Circuit Interrupter Protection
b) Other Than Dwelling Units - All 125/250 volts, single phase, 15-20 amperes receptacles installed in the following locations shall be of GFCI protection:
- Bathrooms
- Commercial and institutional kitchens
- Rooftops
- Outdoor in public areas
BRANCH CIRCUITS
Ground Fault Circuit Interrupter Protection
c) __________ All 125/250 volts, 15-20 ampere receptacles shall be GFCI protection.
.Boat Hoists
BRANCH CIRCUITS
Circuits Derived from an Autotransformer
- Branch circuits shall not be derived from ___________ unless the circuit being supplied has a ___________ connected to the supplying ___________.
autotransformers
grounded conductor
autotransformer supply
BRANCH CIRCUITS
A device intended to provide protection from the effects of arc faults by recognizing characteristics unique to arcing and by functioning to de-energize the circuit when an arc fault is detected.
Arc-Fault Circuit Interrupter (AFCI)
BRANCH CIRCUITS
Dwelling Unit Bedrooms
- All 115V and/or 230V, single phase, 15 and 20A shall be protected by a listed AFCI, combination type installed to provide ________ of the branch circuit. This requirement is effective since last __________
protection
January 1, 2014.
BRANCH-CIRCUIT RATINGS
Conductors - Minimum Ampacity and Size
In General - Branch-circuit conductors shall have an ampacity not less than the ________ to be served. Branch circuit conductors which supplies continuous load and combination thereof shall have an ampacity not less than____% of the continuous load.
maximum load
125%
BRANCH-CIRCUIT RATINGS
Conductors - Minimum Ampacity and Size
Household Ranges and Cooking Appliances - Fore ranges of ____kw or more rating, shall have a minimum-branch circuit rating of ______A.
8¾ kW
40 amperes
BRANCH-CIRCUIT RATINGS
Conductors - Minimum Ampacity and Size
Branch circuit conductors that supply other loads, other than cooking and heating appliances shall have a conductor not smaller than ________(mm2)
2.0 mm2 (1.6 mm dia.)
BRANCH-CIRCUIT RATINGS
Receptacle Outlets
a) General Provisions - In every kitchen, family room, dining room, living room, parlor, library, den, sunroom, bedroom, recreation room, or similar room or area of dwelling units, receptacle outlets shall be installed in accordance with the following provisions:
1. Spacing - Not more than _______(mm)horizontally from the other receptacle outlet.
2. Wall Space - Shall provide outlets for any space ________(mm)or more than in width (including space measured around corners) and unbroken along the floor line by doorways, fireplaces, etc.
3. Floor Receptacles - Not counted as part of the required num. of receptacle unless________(mm) away from the wall.
1800 mm (1.8m)
600 mm
450mm
BRANCH-CIRCUIT RATINGS
Receptacle Outlets
b) Countertops - In kitchens and dining rooms of dwelling units, receptacle outlets shall be of the installed in accordance with the following:
1. Wall Counter Spaces - Counter spaces that are _____(mm) or wider requires a receptacle be installed _____(mm) measured horizontally from it.
2. Island or Peninsular Counter Spaces - At least one receptacle shall be installed at each island counter space with a long dimension of _______(mm) or greater and a short dimension of ______(mm) or greater. When a rangetop or sink is dividing the island at dimensions of less than ______(mm), outlets are not required.
3. Receptacle Outlet Location - Receptacle outlets shall be located above, but not more than_____(mm) above, the countertop.
300 mm, 600 mm
600 mm, 300 mm, 300 mm
500 mm
BRANCH-CIRCUIT RATINGS
Receptacle Outlets
c) Bathrooms - Shall have at least one receptacle within ______ (mm)from the outside edge of each basin.
d) Outdoor Outlets - For a one-family dwelling and each unit of dwelling units shall have at least one accessible outlet at grade level not more than _______(mm)in front and back of the dwelling unit.
e) Laundry Areas - Shall have at least _ receptacle installed for the laundry.
f) Basement and Garages - Shall have at least _receptacle outlet be installed.
g) Hallways - In dwelling units, ______(mm)or more in length shall require at least one receptacle outlet.
h) Show Windows - At least one receptacle directly ______(mm) above for each linear width.
i) Heating, Air-conditioning and Refrigeration Equipment Outlet - Special individual outlets shall be installed and be located on the same level _______(mm) within the equipment
900 mm 2000 mm 1 1 3000 mm (3m) 3600 mm 7600 mm
BRANCH-CIRCUIT RATINGS
Lighting Outlets Required(6)
- Habitable Rooms
- Hallways, Stairways, Attached Garages, Detached Garages with Electric Power
- Attached and Detached Garages
- Interior Stairways (six risers or more)
- Storage and Equipment Spaces
- Guest Rooms or Guest Suites
FEEDERS
Minimum Rating and Size
a) In General - Feeders shall have an allowable ampacity not less than the noncontinuous load plus _____% of the continuous load.
125%
FEEDERS
Minimum Rating and Size
b) Ampacity Relative to Conductors - Feeders for systems with _______V`, or less, shall have an ampacity not less than that of the service and carry the total load supplied with _______A or less.
600 volts
55 amperes
FEEDERS
Feeders with Common Neutral
- ______ of __________(3) can have common neutral.
Two or three sets
3-wire feeders or two sets of 4-wire or 5-wire feeders
BRANCH CIRCUIT, FEEDER, AND SERVICE CALCULATIONS
Calculations
a) Voltages - Unless other voltages are specified, for purposes of calculating branch-circuit and feeder loads, nominal system voltages of _______(10)shall be used.
115, 115/230, 208Y/120, 230, 347, 400Y/230, 460Y/265, 460, 600Y/347, and 600V
BRANCH CIRCUIT, FEEDER, AND SERVICE CALCULATIONS
Calculations
b) Fractions of an Ampere - An ampere that is less than ___, shall be permitted to be _______.
0.5
dropped
BRANCH CIRCUIT, FEEDER, AND SERVICE CALCULATIONS
Calculations
c) Other Loads - All Occupancies
Heavy-Duty Lampholders - minimum of ____VA
Sign and Outline Lighting - t minimum of _____VA
Show Windows - ____VA per_______(mm) show window.
Track Lighting - ____VA for every _____(mm) of track lighting.
Banks and Office Buildings - at ____VA/m2
600VA.
1200VA.
200VA, 300 mm
150VA, 600mm
28VA/m2
BRANCH CIRCUIT, FEEDER, AND SERVICE CALCULATIONS
Calculations
Receptacle Outlets
1 Yoke - Each single or multiple receptacle is ____VA
Multiple Receptacles (4 or more) - ____VA per receptacle
180VA
90 VA
BRANCH CIRCUIT, FEEDER, AND SERVICE CALCULATIONS
Feeder and Service Load Calculation
see table chart
BRANCH CIRCUIT, FEEDER, AND SERVICE CALCULATIONS
Optional Feeder and Service Load Calculations
Heating and Air-Conditioning Load
___% - Air-Conditioning and Cooling
___% - Heat Pump without any Supplementary Electric Heating
___% - Electrical Thermal Storage
___% - Heat Pump Compressor and 65% - Supplemental Electric Heating
___% - Electric Space Heating less than 4 Controlled Units
___% - Electric Space Heating for 4 or more Controlled Units
100%
100%
100%
100%
65%
40%
BRANCH CIRCUIT, FEEDER, AND SERVICE CALCULATIONS
Multifamily Dwelling
- It shall be permissible to calculate the load of a feeder or service that supplies ____ or more dwelling units of a multifamily dwelling in accordance with the table if all the following conditions are met:
- No dwelling unit is supplied by more than___ feeder.
- Each dwelling unit is equipped with ____________
three
one
electric cooking equipment
OUTSIDE BRANCH CIRCUITS AND FEEDERS
Conductor Size and Supportsa) Overhead Spans - Individual conductors shall not be smaller than the following:
For 600 volts, nominal, or less
15m Length - _______(mm2) copper and _________(mm2) aluminum
Longer than 15m - _________(mm2) copper and _____(mm2) aluminum
- 5 mm2 (2.6 mm. dia.)
- 0 mm2 (3.2 mm. dia.)
8.0 mm2 (3.2 mm. dia.)
14 mm2
OUTSIDE BRANCH CIRCUITS AND FEEDERS
Conductor Size and Supportsa) Overhead Spans - Individual conductors shall not be smaller than the following:
For over 600 volts
Open Individual Conductors - ___(mm2) copper and ____(mm2) aluminum
Conductors in Cable - _______(mm2) copper and _____(mm2) aluminum
14 mm2
22 mm2
8.0 mm2 (3.2 mm. dia.)
14 mm2
OUTSIDE BRANCH CIRCUITS AND FEEDERS
Conductor Size and Supportsa) Overhead Spans - Individual conductors shall not be smaller than the following:
Festoon Lighting - Overhead conductors for festoon lighting shall not be smaller than _______(mm2) unless the conductors are supported by messenger wirings.
3.5 mm2 (2.0 mm dia.)
OPEN CONDUCTOR SPACING (CLEARANCES) - FEEDERS AND CONDUCTORS
Conductor on Poles
Shall have a separation of not less than ______(mm) where not placed on racks or brackets.
a) Power conductors below communications conductors - _______(mm)
b) Power conductors alone or above communications conductors:
1. 300V or less - ______(mm)
2. Over 300V- ______(mm)
c) Communications conductors below power conductors -________(mm)
d) Communications conductors alone -_______
300 mm
750 mm 600 mm 750 mm Same as power conductors No requirement
OVERHEAD SERVICE
________ The overhead service conductor from the last pole or other aerial support and including splices if any, connecting to the service entrance conductor in a building or other structures
Service Drop
Overhead Service Locations
Shall be: (4)
- Equipped with rain-tight service head.
- Located above the point of attachment of the service-drop conductors.
- Drip loops formed on individual conductors to prevent moistures.
- Arranged that water will not enter service raceway or equipment.
Overhead Service Drop Conductors - The minimum size of overhead service drop conductors:
a) Copper - ________
b) Aluminum or Copper Clad - _______
8.0 mm2 (3.2 mm dia.)
14 mm2
OPEN CONDUCTOR SPACING (CLEARANCES) - FEEDERS AND CONDUCTORS
Clearance from Ground
- Overhead spans of conductors not over ____(mm), nominal, shall have a clearance of not less than the following:
a) _________(mm) - Above finished grade, sidewalks, pedestrians (150V per phase max.). And, at electric service entrance to buildings, also at the lowest point of the drip loop.
b) _________(mm) - Over residential property, driveways, and commercial properties not subject to traffic where voltage does not exceeds 300V per phase max.
c) _________(mm) - Over residential property, driveways, and commercial properties not subject to traffic where voltage exceeds over 300V per phase.
d) _________(mm) - Over public streets, alleys, roads, parking areas subject to truck traffic, driveways, cultivated, grazing, forest, and orchard.
e) _________(mm) - In any direction of the water level of swimming pools.
600V
3000 mm 3600 mm 4500 mm 5500 mm 6900 mm
OPEN CONDUCTOR SPACING (CLEARANCES) - FEEDERS AND CONDUCTORS
Clearances from Buildings for Conductors of Not Over 600 Volts, Nominal
a) Above Roofs - Shall not be less than ______(mm) above roof surface and maintained at a distance not less than ______(mm) in all directions from the edge of the roof.
Voltage does not exceed 300V and the roof has a slope of 100 mm in 300 mm or greater - A reduction of ______(mm) in clearance is permitted.
b) From Non-Building or Non-Bridge Structures - from signs, chimneys, radio and television antennas, tanks - vertical, diagonal, and horizontal - shall not be less than ____(mm).
c) Horizontal Clearances - Clearances shall not be less than _____(mm)
d) Finals Spans - Final spans of feeders or branch circuits:
1. Clearance from Windows - Shall be kept not less than ______(mm)
- Vertical Clearance - _____(mm) measured horizontally of, platforms or projections.
- Building Openings - Overhead branch circuits shall not be installed beneath openings through which materials may be moved.
- Zone for Fire Ladders - A clear space (zone) at least _______(mm) wide left adjacent of the building to facilitate rising of ladders when necessary for fire fighting.
2500 mm
900 mm
900 mm
900 mm
900 mm
900 mm
900 mm
1800 mm.
SERVICES
Buildings or Structures requiring Additional Feeders/Service Entrance:
a) Special Conditions - Additional feeder or branch circuits shall be permitted to the ff.
- Fire pumps (high pressure) for the building
- Emergency systems
- Legally required standby systems
- Optional standby systems
- Parallel power production systems
- Multiple sources of supply for the purpose of enhanced reliability
SERVICES
Buildings or Structures requiring Additional Feeders/Service Entrance:
b) Special Occupancies - By special permission, additional feeder or branch circuit shall be permitted:
- Multiple-occupancy buildings where there is no available space for service equipment accessible to all occupancies.
- A single building/structure sufficiently large to make two or more supplies necessary.
SERVICES
Buildings or Structures requiring Additional Feeders/Service Entrance:
c) Capacity Requirements - Where the capacity requirements are in excess of ________ amperes at a supply voltage of 600Vor less
2000
SERVICES
Buildings or Structures requiring Additional Feeders/Service Entrance
d) Different Characteristics - Additional services shall be permitted for _________________
different voltages, frequencies, or phases, or for different uses, such as for different rate schedules.
SERVICES
Buildings or Structures requiring Additional Feeders/Service Entrance
Conductors Considered Outside the Building
- The conductors considered outside the building shall be in the following conditions:
a) Installed under not less than ______(mm) of concrete beneath a building/structure
b) Encased in concrete or brick not less than_______(mm) thick
c) Installed in any _____
d) installed in conduit and under not less than ______(mm)of earth burial
50 mm
50 mm
vault construction
450 mm
UNDERGROUND SERVICE
Clearance of Service Lateral:
a) ____(mm) - directly buried cable
b) ______(mm) - RMC or IMC installation
c) ______(mm) - PVC approved for direct burial without concrete encasement
d) _______(mm) - other approved raceway for direct burial
600 mm
150 mm
450 mm
450 mm
UNDERGROUND SERVICE
Mounting Supports
- Service cables shall be supported by ____ or other approved means within ______(mm) of every service head, gooseneck, or connection to a raceway or enclosure at intervals not exceeding _____(mm).
straps
300 mm
750 mm
UNDERGROUND SERVICE
Equipments Connected to the Supply Side Service Disconnect:
shall be: (10)
a) Cable limiters or other current-limiting devices
b) Meters and meter sockets (not in excess of 600V)
c) Meter disconnect switches (not in excess of 600V)
d) Fusible switches or circuit breakers
e) Instrument transformers (current and voltage), impedance shunts, load management devices, arresters
f) Taps used only to supply load management devices
g) Solar photovoltaic systems, fuel cell systems, interconnected electric power production sources
h) Control circuits for power-operable service disconnecting means
i) Ground-fault protection systems or transient voltage surge suppressors
j) Fusible disconnect switch or circuit breaker
UNDERGROUND SERVICE
Services Exceeding 600 Volts, Nominal
- Conductors not smaller than _____ unless in multi-conductor cable. Multi-conductor cable shall not be smaller than _______.
14 mm2
8.0 mm2 (3.2 mm dia.)
UNDERGROUND SERVICE
Maximum Number of Disconnects
- Shall consists of not more than _ switches or sets of circuit breakers, or a combination thereof shall be in a group of separate enclosures in a _________.
6
switchboard
UNDERGROUND SERVICE
Manually or Power Operable
a) _______- A manually operable switch or circuit breaker shall be equipped with a handle or other suitable operating means.
b) _________ - It can be manually or power-operable/circuit breaker, provided it can be opened by hand during power failure.
Manually operable
Powered-operated switch
UNDERGROUND SERVICE
Rating of Service Disconnecting Means:
a) One Circuit Installation- Supplying only limited loads of a single branch circuit; the service disconnecting means shall have a rating of not less than ___A.
b) One Circuit Installation-Dwelling Unit - For dwelling units with a single branch circuit a service disconnect means of not less than ___A is permitted.
c) Two-Circuit Installations - For installation of not more than 2 wire branch circuits, the service disconnecting means shall have a rating of not less than ___.A
d) One Family Dwelling - The service disconnect shall have a rating of not less than ___A, 3-wire.
e) All Others - Shall have a rating of not less than ___A.
15A
20A
30A
60A
30A
OVERCURRENT PROTECTION
Standard Ampere Ratings
- The standard ampere ratings for fuses and inverse time circuit breakers shall be considered
15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100, 110, 125, 150, 175, 200, 225, 250, 300, 350, 400, 450, 500, 600, 700, 800,
1000, 1200, 1600, 2000, 2500, 3000, 4000, 5000, and 6000 amperes. Additional standard ampere ratings for fuses shall be 1, 3, 6, 10, and 601. The use of fuses and inverse time circuit breakers with nonstandard ampere ratings shall be permitted.
OVERCURRENT PROTECTION
Fuses or Circuit Breakers in Parallel
- Fuses and circuit breakers shall be permitted to be connected in parallel where they are ________and listed as a unit. Individual fuses, circuit breakers, or combinations thereof ______ otherwise be connected in parallel.
factory assembled in parallel
shall not
OVERCURRENT PROTECTION
Thermal Devices
- Thermal relays and other devices not designed to open short circuits or ground faults shall not be used for the __________ against overcurrent due to short circuits or ground faults, but the use of such devices shall be permitted to __________ from overload if protected.
protection of conductors
protect motor branch-circuit conductors
OVERCURRENT PROTECTION
Grounded Conductor
- No overcurrent device shall be connected in ____ with any conductor that is intentionally grounded.
series
OVERCURRENT PROTECTION
Change in Size of Grounded Conductor
- Where a change occurs in the size of the ungrounded conductor, a ________ shall be permitted to be made in the size of the grounded conductor.
similar change
OVERCURRENT PROTECTION
Locations in or in Premises
a) Accessibility - Overcurrent devices shall be readily accessible and shall be installed so that the center grip of the handle switch at its highest position is not more than ____m from the floor.
b) Occupancy - each occupant shall have ready access to all overcurrent devices protecting the conductors supplying that occupancy.
c) Not Exposed in Physical Damage
d) Not in Vicinity of Easily Ignitable Materials
e) Not Located in Bathrooms
f) Installed in a Vertical Position
2 meters
OVERCURRENT PROTECTION
Circuit Breakers
a) Method of Operation - Circuit breakers shall be ___ and capable of being closed and opened by ____ operation. Their normal method of operation by other manual means, such as electrical or pneumatic, shall be permitted if means for manual operation are also provided.
b) Indication - The indication of ―up‖ position of the handle is ―__‖ position and a ―down‖ position is indicating it is in ―__‖ position.
c) ________ - A circuit breaker shall be of such design that any alteration of its trip point (calibration) or the time required for its operation requires dismantling of the device or breaking of a seal for other than intended adjustments
trip free
manual
on
off
Nontamperable
OVERCURRENT PROTECTION
d) Marking
1. Durable and Visible - Circuit breakers shall be ____A with their ampere rating in a manner that will be durable and visible after installation
2. Location - Circuit breaker rated at ___A_ or less and ____V or less shall have the ampere rating molded, stamped, etched or similarly marked into their handles.
3. Interrupting Rating - Each device with an interrupting rating other than _____shall have its interrupting rating shown on the circuit breaker.
4. Used as Switches - Circuit breakers used as switches in 120V and 277V fluorescent lighting circuits shall be listed and shall be marked ________(2).
5. Voltage Marking - Circuit breakers shall be marked with a voltage rating ____________ that is indicative of their capability to interrupt fault currents between phases or phase to ground.
marked
100A, 600V
5000A
SWD or HID
not less than the nominal system voltage
OVERCURRENT PROTECTION
Overcurrent Protection over 600V, Nominal
a) Overcurrent Relays and Current Transformers - Circuit breakers used for overcurrent protection of _-phase circuits shall have a minimum of _ overcurrent relay elements operated from _- current transformers.
b) Fuses - a fuse shall be connected in ____ with each ungrounded conductor
3
3
3
series
GROUNDING AND BONDING
General Requirements for Grounding and Bonding:
a) Electrical System Grounding - Shall have connections that limit the voltage imposed by lightning, line surges, or unintentional contact with higher-voltage lines that will stabilize the ________.
b) Grounding of Electrical Equipment - Non-current carrying conductive materials, electrical conductors, or equipment shall be connected to earth so as to _________.
c) Bonding of Electrical Equipment - Non-current carrying conductive materials forming part of such equipment connected together establishing an ―______________”.
d) Bonding of Electrically Conductive Material and Other Equipment - Electrically conductive materials that are likely to be energized shall be _______ establishing “effective ground-fault current path”.
e) Effective Ground-Fault Current Path - A ________ current path for the fault current to carry the maximum ground-fault current.
voltage to earth
limit the voltage to ground
effective ground-fault current path
connected together
low impedance
GROUNDING AND BONDING
Connection of Grounding and Bonding Equipment
a) Connected by exothermic welding, listed pressure contactors, listed clamps.
b) Connection devices or fittings that depend solely on solders shall not be used.
c) Sheet metal screws shall not be used.
d) Non-conductive coatings shall be removed such as paint, lacquer, and enamel.
GROUNDING AND BONDING
Circuits Not To Be Grounded (4)
- Electric cranes operating over combustible fibers in Class III locations.
- Circuits in health care facilities.
- Circuits for equipment within electrolytic cell working zone.
- Secondary circuits of lighting systems.
GROUNDING AND BONDING
Main Bonding Jumper and System Bonding Jumper (3)
- Copper or other corrosion-resistant material.
- Wire, bus, screw, or similar suitable conductor.
- Screws shall be identified with a green finish.
GROUNDING AND BONDING
Grounding Electrode Conductor for Multiple Separately Derived Systems
- The common grounding electrode conductor shall not be smaller than _____(mm2) copper or ____(mm2) aluminum.
80 mm2
125 mm2
GROUNDING AND BONDING
Grounding Electrodes (Electrodes Permitted for Grounding)
Metal Underground Water Pipe - Any metal underground water pipe ______(mm) or more and electrically continuous to the points of connection of the grounding electrode conductor and the bonding conductors.
Other Local Metal Underground Systems or Structures
3000 mm
GROUNDING AND BONDING
Grounding Electrodes (Electrodes Permitted for Grounding)
Plate Electrodes - Shall not expose _____ of surface to exterior. Iron or steel electrodes, ___(mm) thick. Nonferrous metal electrodes, at least ____(mm) thick. And, plate electrodes shall not be less than ____(mm) below the earth’s surface.
(2ft 2) 0.186 m2
6 mm
1.5 mm
750 mm
GROUNDING AND BONDING
Grounding Electrodes (Electrodes Permitted for Grounding)
Metal Frame of the Building - _______(mm) or more of a single structure metal member in direct contact with earth or encased in concrete that is in direct contact with the earth.
3000 mm
GROUNDING AND BONDING
Grounding Electrodes (Electrodes Permitted for Grounding)
Concrete Encased Electrode - An electrode encased by at least 50 mm of concrete located near the bottom of concrete foundation or footing. It has _____(mm) of one or more electrically conductive steel coated bars.
6000 mm
GROUNDING AND BONDING
Grounding Electrodes (Electrodes Permitted for Grounding)
Ground Ring - Bare copper conductor not smaller than _____(mm2) encircling the building/structure. ______(mm) or more in length and buried at a depth not less than _______(mm)
30 mm2,
6000 mm,
750 mm
GROUNDING AND BONDING
Grounding Electrodes (Electrodes Permitted for Grounding)
Rod and Pipe Electrodes - Rod and pipe electrodes shall not be less than ______(mm) in length.
a) Electrodes of pipe or conduit shall not be smaller than _____(mm).
b) Electrodes of iron or steel shall be at least ___(mm) in diameter.
2400 mm
20 mm
16 mm
GROUNDING AND BONDING
Electrodes Not Permitted for Grounding
- Metal underground gas piping system
2. Aluminum electrodes
GROUNDING AND BONDING
Bonding of Services
- The non-current carrying metal parts listed should be effectively ______ together:
a) Service raceways, cable trays, cable framework, auxiliary gutters, service cable armor or sheath.
b) Service enclosures containing service conductors, meter fittings, boxes, materials interposed in the service raceway or armor.
c) Any metallic raceway or armor enclosing a grounding electrode.
bonded
GROUNDING AND BONDING
Equipment Bonding Jumpers
a) Size - Equipment Bonding Jumper (Supply Side) - The minimum size of bonding jumper shall be _____(mm2) for copper and _____(mm2) for aluminum or copper-clad aluminum.
8.0 mm2
14 mm2
GROUNDING AND BONDING
Equipment Bonding Jumpers
b) Size - Equipment Bonding Jumper (Load Side) - The largest underground circuit conductors supplying the equipment shall not be smaller than _______
2.0 mm2 (1.6 mm. dia.).
GROUNDING AND BONDING
Equipment Grounding and Equipment Grounding Conductors
a) Equipment Fastened in Place or Connected by Permanent Wiring Methods (Fixed) - Exposed non- current carrying metal parts or fixed equipment that are likely to become energized shall be grounded:
- Where within ______ vertically or ______ horizontally of ground or grounded metal objects and subject to contact by persons.
- In a wet or damp location and not isolated.
- Where in electrical contact with metal.
- In hazardous locations.
- Supplied by a metal-clad, metal sheathed metal-raceway, or other equipment grounding methods.
- Operates with a terminal at over _____ to ground.
2400 mm
1500 mm
150 volts
GROUNDING AND BONDING
Equipment Grounding and Equipment Grounding Conductors
b) Equipment Fastened in Place or Connected by Permanent Wiring Methods (Fixed) - Specific
- Exposed, non-current carrying metal parts of the kinds of equipment and non-current carrying metal parts shall be grounded: (13)
- Switchboard Frames and Structures
- Pipe Organs - generator and motor from frames in an electrically operated pipe organ.
- Motor Frames
- Enclosures for Motor Controllers
- Elevators and Cranes
- Garages, Theaters, and Motion Picture Studios
- Electric Signs
- Motion Picture Projection Equipment
- Power-Limited Remote-Control, Signaling, and Fire Alarm Circuits
- Luminaries (Lighting Fixtures)
- Skid Mounted Equipment
- Motor-Operated Water Pumps (including submersible type)
- Metal Well Casings
GROUNDING AND BONDING
Equipment Grounding and Equipment Grounding Conductors
c) Equipment Connected by Cord and Plug
- In hazardous locations
- Operated at over 150 volts to ground
- In residential and non residential occupancies: (8)
- Refrigerators, freezers, and air-conditioners
- Clothes-washing, clothes-drying, dish-washing machines; kitchen waste disposer, IT equip. sump pumps and electrical aquarium equipments.
- Hand-held motor-operated tools, stationary and fixed motor-operated tools, light industrial motor-operated tools.
- Motor-operated appliances of the following types: hedge clippers, lawn mowers, snow blowers, and wet scrubbers.
- Portable handlamps
- Cord-and-plug connected appliances used in damp or wet locations
- Tools likely to be used in wet or conductive locations
GROUNDING AND BONDING
Equipment Grounding and Equipment Grounding Conductors
d) Nonelectric Equipment - Equipments listed shall be grounded:
Frames and tracks of electrically operated cranes and hoists
Frames of non-electrically driven elevator cars to which electrical conductors are attached
Hand-operated metal shifting ropes or cable of electric elevators
GROUNDING AND BONDING
Identification of Equipment Grounding Conductors
a) Shall be permitted to be bare, covered, or insulated.
b) Green or green with one or more yellow stripes outer finish.
c) Minimum size of equipment grounding conductor is _______ (mm2 )for copper and __________ (mm2) for copper aluminum or copper-clad aluminum
- 0 mm2 (1.6 mm. dia.)
3. 5 mm2 (2.0 mm. dia.)
GROUNDING AND BONDING
Identification of Wiring Device Terminals:
- ____, not readily removable terminal screw with a hexagonal head.
Green
GROUNDING AND BONDING
Identification of Wiring Device Terminals:
- Green, _________ , not readily removable terminal nut.
- Green pressure wire connector. If the terminal is not visible, the conductor entrance hall shall be marked with the word _______, or letters ―G‖ or ―GR‖ or otherwise identified by distinctive green color.
hexagonal
GROUNDING AND BONDING
Identification of Wiring Device Terminals:
- Green pressure wire connector. If the terminal is not visible, the conductor entrance hall shall be marked with the word _______, or letters ―G‖ or ―GR‖ or otherwise identified by distinctive green color.
green or ground
GROUNDING AND BONDING
Size of Direct-Current Grounding Electrode Conductor:
- Shall not be smaller than ________(mm2) for copper and _____ (mm2) aluminum.
- Shall not be smaller than the largest conductor.
- Connected to a rod, piper, or plate electrode.
- Connected to a concrete-encased electrode.
- Connected to a ground ring.
8.0 mm2
14 mm2
GROUNDING AND BONDING
Instrument, Meters and Relays:
a) Such Cases should be Grounded:
1. Not on switchboards and at _____V or more.
2. On _______ switchboards having no live parts in front of the panel.
3. On live-front switchboards having _____. Mats of insulating rubber should be provided for the operator where the voltage exceeds ____V.
b) Instrument Grounding Conductor
- The grounding conductor for secondary circuits of instrument transformers and for instrument cases shall not be smaller than _______(mm2) copper or _________(mm2) for aluminum.
300 volts
dead-front
exposed live parts , 150 volts
- 5 mm2 (2.0 mm dia.)
- 5 mm2 (2.6 mm dia.)
SURGE ARRESTERS
Surge Arrester Selection:
a) Circuits of less than 1000 Volts - surge arresters installed on a circuit of less than _______V shall comply with all of the following provisions:
1. The rating shall be equal to or greater than the ______________ voltage available at the point of application.
2. Surge arresters installed on ____ of less than _____V shall be listed.
3. With a _______ rating and shall not be installed at a point on the system where the available fault current is in _______ of that rating.
4. Shall not be installed on ________ systems, impedance grounded systems, or corner grounded delta systems unless listed specifically for use on these systems.
b) Circuits of 1kV and over -Silicon Carbide Types - The rating of a silicon carbide-type surge arrester shall not be less than ____% of the maximum continuous phase-to-ground voltage
1000 volts
maximum continuous phase-to-ground power frequency
circuits, 1000 volts
short circuit current
excess
ungrounded
125%
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Uses Not Permitted
- A transient voltage surge suppressor shall not be installed in the following:
- Circuits exceeding 600 volts.
- On ungrounded systems, impedance grounded systems, or corner grounded delta systems unless listed specifically for use on these systems.
- Where the rating of the TVSS is less than the maximum continuous phase-to-ground power frequency voltage available at the point of application
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Conductor Size
- Line and ground connecting conductors shall not be smaller than _________(mm2) copper or ________(mm2) aluminum.
- 0 mm2 (1.6 mm dia.)
3. 5 mm2 (2.0 mm dia.)
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Protection for Ordinary Buildings
- An ordinary building is one of common or conventional design and construction used for ordinary purposes, whether commercial, farm, industrial, institutional, or residential.
a) Classifications
1. ___________ - Less than 23 m in height.
2. ___________ - More than 23 m in height.
Class I ordinary buildings
Class II ordinary buildings
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Protection for Ordinary Buildings
b) Materials
- The materials of which protection systems are made shall be resistant to _______ or shall be _______ against corrosion.
1. Copper - It shall be grade ordinarily designed with ___% conductivity when annealed.
2. Copper Alloys - It shall be substantially resistant to ______ as copper.
3. Aluminum - When aluminum is used, care shall be taken not to use it in ___________ or elsewhere where it will rapidly deteriorate.
corrosion
acceptably protected
98%
corrosion
contact with the earth
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Protection for Ordinary Buildings
c) Configuration (7)
Gable, Hip, Broken Gable, Flat, Mansard, Gambrel
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Terminals on Roofs
a) Flat or Gently Sloping Roofs - Additional air terminals at intervals not exceeding ___m. Gently sloping are roofs having a span of __m/less and a pitch of __or less or exceeding ___m with __ pitch or less.
15m
12m, 1/8
12m, 1/4
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Terminals on Roofs
b) Lower Roofs - One-to-one zone protection for buildings which exceed __m above grade. One-to-two zone protection for buildings not exceeding __m.
15m
15m
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Terminals on Roofs
c) Dormers - Higher than the main roof shall be protected with ______ along ______.
air terminals
end ridges
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Terminals on Roofs
d) Roofs with Intermediate Ridges - Air terminals not exceeding ____(mm) for roofs with ______ ridges.
7600mm
parallel
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Terminals on Roofs
e) Irregular Roof Lines - Air terminals located within ______(mm) of the outermost projection of the roof edge.
600mm
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Terminals on Roofs
f) Open Areas in Flat Roofs - Shall be protected if their perimeter exceeds __m provided either rectangular dimension exceeds ___m.
92 m
15 m
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Terminals on Roofs
g) Doomed Or Curved Structures - Air terminal located at the ___of the curve or dome.
apex
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Terminals on Roofs
h) Chimneys - Air terminals shall be placed with ___(mm) thick. Chimney air terminals shall be attached to the chimney so that no outside corner of the chimney is more than____(mm) from an air terminal.
4.8 mm
600 mm
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Gradual Bends
- No bend of angle of less than ____ nor shall have a radius of bend less than ____(mm)
90 degrees
230 mm
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Two Way Path Exceptions
- Permitted w/o an extra downlead provided lower roof conductor not more than 12m.
One-Way Drops
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Two Way Path Exceptions
- Air terminals may be ―dead ended‖ with only one path provided the conductor run from the air terminal to a main conductor is not more than 4900 mm in total length.
Dead Ends
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Down Conductors - At least __ down conductors shall be provided of any kind of structure, including steeples.
- Number of Down Conductor - Average distance between conductors shall not exceed ___m. Irregularly shaped structures may require extra down conductors to provide a two-way path to ground.
- Protecting Down Conductors - Down conductors located in runways, driveways, school playgrounds, cattle yards, public walks shall be ____ to prevent from physical damage.
two
30m
guarded
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Grounding
- Ground Terminal (Rods) - Shall be not less than ________(mm). and ______(mm). Rods shall be copper-clad steel, solid copper or stainless steel.
- Ground Rod Clamps - Clamps shall make contact with the ground rod for a distance of ___. Clamps shall be secured with at least _______(2).
12.7 mm in dia
2400 mm long
38 mm
two bolts or cap screws
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Common Grounds
- All grounding mediums shall be bonded together which includes _________(3). Piping system including water service, well casings within ___(mm), gas piping, underground conduits, underground liquefied petroleum-gas piping systems.
electric, telephone, antenna
7600 mm
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Metal Bodies
a) Bonding Requirements for Metal Bodies of Conductance - Bonded to the system having a surface contact area of not less than _____m2
0.0019 m2
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Metal Bodies
b) Bonding Requirements for Metal Bodies of Inductance - Bonded to their closes point using secondary bonding conductors and fittings. Connections made within ____(mm).
1800 mm
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Anchors
- Masonry anchors shall have a diameter of not less than ____(mm) and shall be set with___. ___ shall be tight against moisture and the effect of frost and capable of withstanding a pull test of___N.
6.4 mm
care
Fit
445N
TRANSIENT VOLTAGE SURGE SUPPRESSOR (TVSS)
Splicers and Clamps
- Splicers and clamps shall be permitted to be connected to ________ or ______ and shall withstand a pull test of____N.
―end-to-end‖ ―tee‖
―Y‖ splices
890N
.
.