Chapter 3.1, 3.2, 3.3, 3.4 Flashcards
From Electrical Codes to Grounded and Ungrounded Conductors
Chapter 3 title
Building Electrical Design Principles
Chapter 3.1 Title
Electrical Codes, Licenses, and Permits
An _________ specifies the __________ necessary for protecting _______ and _________ from the improper use of ________ and _______________.
electrical code, written provisions, people, property, electricity, electrical equipment
The __________________ is a set of __________ and ___________ in the form of a __________ that can be adopted into local law by the local government entity.
National Electrical Code, specifications, standards, model code
The _______ was established in _____ through the combined efforts of insurance, electrical, architectural, and other interested groups.
NEC, 1897
In ______, the _______________________ became the sponsor of the NEC and continues to act in this capacity.
1911, National Fire Protection Association (NFPA)
PEC - 2017
Philippine Electrical Code 2017
Purpose of PEC
Practical Safeguarding
Adequacy
Intended as a Design Specification
Relation to other International Standards
____________ of persons and property from hazards arising from the use of electricity.
*Purpose of PEC
Practical Safeguarding
Contains provisions that are considered minimum requirements necessary for safety.
*Purpose of PEC
Adequacy
________ often occur because of overloading of wiring systems by methods or usage not in conformity with this code.
FPN No 1,Hazards
It is highly recommended that a licensed electrical practitioner be consulted for any electrical requirements, including changes.
FPN No 2
Fire Hazard, electrocution, serious injury or even death may also occur with lack or improper maintenance of wiring system.
FPN No 3
Intended as a ____________ or an __________ to qualified persons.
*Purpose of PEC
design specification, instruction manual
The requirements in this code address the fundamental principles of protection for safety contained in _____________, Electrical Installation of Buildings.
*Purpose of PEC
Relation to other International Standards, Section 131 of IEC 60364-1
Encompasses protection against thermal effects, protection against overcurrent, protection against fault currents, and protection against overvoltage.
FPN. IEC 60634-1, Section 131
*Scope
This code ______ the installation of electrical conductors, equipment, and raceways; signaling and communications conductors.
covers
*Scope
Does __________ the (1) installations in railway rolling stock, aircraft or automotive vehicles. (2) installation of railways for generation, transformation, transmission, or distribution of power used.
not cover
*Authority
This code has been approved and adopted by the _____________ and ________.
Board of Electrical Engineering, PRC
*Authority
By virtue of authority vested in the Board under ________, it hereby direct strict adherence to the provisions of this code.
RA 7920
*Enforcement
This code is intended for mandatory application by the ____________ over ____________.
office of the Building Official/ EE, electrical installations
*Enforcement
The__________________ shall have the responsibility of implementing the provisions of this code.
office of the Building Official/ EE
*Enforcement
This code may require new products, constructions, or materials that may not yet be available at the time this code is adopted.
T
- are those that identify actions that are specifically required or prohibited and are characterized by the use of terms shall or shall not
Mandatory Rules
- identify actions that are allowed but not required, are normally used to describe options or alternative methods.
Permissive Rules
- references to other standards, references to related sections of this code.
Explanatory Material
Example- Information related to a code rule in the form of fine print notes (FPN)
- are not part of the enforceable requirements of the PEC1, but are included for information purposes only.
Appendices
Today, all electrical equipment, applications, and devices should meet specific ______________ based on regular product testing. An __________ product meets _________ safety standards as determined by extensive testing by an independent testing company or organization.
safety standards, approved, minimum
- is a not- for- profit product safety testing and certification organization.
Underwriters Laboratory Inc. (UL)
- is the leading third party certification org. in the United States and has been evaluation products in the interest of public safety since _____.
Underwriters Laboratory Inc. (UL), 1894
_______________ is the leading trade association in US representing the interests of electrical manufacturing.
The National Electrical Manufacturing Association
- is known in most other countries in North and South America as ______________.
The Council for Harmonization of Electrotechnical Standards of the Nations of the Americas, Consejo de Armonizacion de Normas Electrotechnicians de ka Naciones de las Americas (CANENA)
The purpose of __________________ is to facilitate and promote the development of harmonized electrotechnical codes and standards and uniform conformity assessment methods.
Consejo de Armonizacion de Normas Electrotechnicians de ka Naciones de las Americas (CANENA)
Most municipalities have local laws that require that any person who wishes to engage in the business of installing electrical systems must be _______. This means that the person must have a minimum number of years of experience working with a licensed electrician and must pass a written test that deals with the electrical code being used and with methods of installations.
licensed
By requiring a ________, it is assured that the _________ knows, at a minimum, the code requirements and the installation procedures.
license, electrician
Most municipalities require that a ______ be issued before any electrical installations may be made on a project. A complete electrical construction drawing may also be required for review and approval by a plans examiner before installation begins.
permit
Municipalities that require a ______ will have electrical inspectors who check the project during regularly scheduled visits. This ____________ will inspect the installation after the rough writing is in but before it is concealed behind construction materials.
permit, inspectors
Chapter 2.3 title
Electrical Construction Drawings
An ____________________ shows the ______ and ________ of an electrical installation.
Electrical Construction Drawings, layout, design
In order to convey the desired information to the contractor, it is a ______ to obtain complete set of construction _______ and _____________ of the building electrical system.
must, drawings, specification
The following construction drawings and details are generally required:
- Complete plans and specifications of all electrical work.
- Labeling criteria of all electrical equipment.
- Lighting floor plans including electrical circuit indicating conduit and wiring sizes.
- Power floor plans including electrical circuits indicating conduit and wiring sizes, equipment and disconnected switches.
- Exit sign/ means of egress lighting location and power supply.
- Panel board schedule
- Lighting Fixture Schedule
- Symbol Schedule Diagrams
Specifications and drawing should be include requirements for:
- Race way and conduit with fittings
- Wire and cable
- Electrical boxes, fittings, and installation.
- Electrical Connections
- Electrical Wiring Devices
- Circuit and Motor Disconnects
- Hangers and Supporting Devices
- Electrical Identification
- Service Entrance and Details
- Overcurrent Protection
- Switchboards
- Grounding
- Transformers
- Panel boards
- Motor Control Centers
- Lighting Fixtures
_________ are specifically used an construction drawings to represent lighting and power distribution components and equipment.
Symbols
Predominantly, there is no specific symbol set is universally accepted by the industry. The symbols on the next slides are typically modified by the engineers consulting firm used on their drawing.
T
_______ are well- arranged on the drawings in the form of a one line diagram.
Symbols
___________ represents the conductors extending between two symbols regardless of the number of ___________.
One line, conductors
The ____________ without any additional identification indicates a ___________ set of conductors either an ungrounded (hot) and grounded conductor or two ungrounded conductors.
single line, two wire
A __________ with _________ indicates a three wire set of conductors and soon.
single line, three slashes
Chapter 3.3 Title
Building System Voltages
Variations from ______ voltages are caused by a number of reasons, including variations in load and changes in conditions in the power supply system.
nominal
_____________- expressed as a ____________ because it varies slightly. __________ can vary from about ___ to ___ of the nominal voltage under normal conditions.
Supply Voltage, nominal voltage, 90 to 105%
________ and ________ voltage systems carry voltages above ______ V may be used in special cases such as for large signage.
Medium and high, 600
___ voltage systems that carry voltages less than 600V are typically used in buildings.
Low
__________ is expressed as a ______ voltage because it varies slightly for the reasons mentioned earlier.
System voltage, nominal
__________ is the initial current carrying conductor in an AC system. The _______ is frequently known as the _____ or _____ conductor because it feeds current to the circuit.
Ungrounded (hot) conductor, ungrounded conductor, hot, live
______________ is required to complete a _________ phase circuit by connecting the ungrounded (hot) conductor to ground. The ______________ is a grounded conductor that serves more than one circuit.
Grounded (neutral) conductor, single , neutral conductor
________________- a third conductor that provides supplementary but important grounding protection.
Grounding (ground) conductor
The _______conductor is not normally a current carrying conductor, but is energized only on a temporary, emergency basis when there is a _______ between an _________________ and ______ associated to the electrical equipment.
grounding conductor, fault, ungrounded (hot) conductor, any metal
The most basic system voltage used.
120 Volt, Alternating Current, Single Phase, Two- wire System (120V AC, 1-2W)
It was used in the first electrical services to buildings; however, nearly all have since been upgraded.
120 Volt, Alternating Current, Single Phase, Two- wire System (120V AC, 1-2W)
_____________________ - the ____________ provided to the switch-board or panelboard is by two conductors; one ________________ conductor carrying _____ and one ______________. Voltage measured between the ungrounded (hot) and neutral conductors is ________.
120 Volt, Alternating Current, Single Phase, Two- wire System (120V AC, 1-2W), service entrance, ungrounded (hot), 120V, neutral conductor, 120V
_________________ - the most common residential electrical service in use today.
120/ 240 Volt, Alternating Current, Single- Phase, Three- Wire System (120/240 V AC, 1-3W)
_____________________- it is also used on a limited basis in light commercial buildings such as small office buildings, churches, and retail shops and stores. On a ______________, a _____ branch circuit provides electrical energy to convenience outlets, small appliances, and light fixtures.
120/ 240 Volt, Alternating Current, Single- Phase, Three- Wire System (120/240 V AC, 1-3W), 120/240 V system, 120 V
A ______ branch circuit serves large appliances and equipment such as electric resistance baseboard heaters, water heaters and air conditioning equipment.
240 V
A _________ branch circuit provides both __________ and _______ to an appliance such as a range and clothes dryer, controls, and light fixtures.
120/240 V, 120V, 240V
Typically, small motors run on ______ and heating elements operate on ________. A __________________ runs continuously through all branch circuits and serves as a ___________ incase of a short circuit.
120V, 240V, grounding conductor, safety circuit
An older electrical service found in small commercial buildings and high-rise buildings where three phase motors, above about 1/2 horsepower, and equipment such as large air conditioners are used. It is not used very often in industry because a ______ system is more economical for large motor loads.
208 Y/120 Volt, Alternating Current, Three-Phase, Four- Wire System (208Y/120 V AC, 3-4W), 480V
______________ - a common electrical service in most modern medium to large commercial buildings. The _____ three phase power is used to power specially designed heavy machinery. High voltage, 277V fluorescent lighting and other single phase devices have also been developed specifically for use with this system. Large retail shopping malls, schools, grocery supermarkets, and office buildings may use this system for its 277V fluorescent lighting capabilities, where fixtures are not located closer than ______ away from windows, platforms, and fire escapes.
480 Y/277 Volt, Alternating Current, Three-Phase, Four- Wire System (480Y/277 V AC, 3-4W), 480V, 3ft
When compared with the 208Y/120 V system, the __________ system has economic advantages from the standpoint of equipment and conductors. Because a given conductor can carry more than twice the VA load at 480 V than at 208 V, the savings in wire size for feeders can be quite significant with the _________ system. Additionally, the smaller current at 480V for any supply transformer capacity permits the use of protective devices with both smaller frame size and interrupting rating. Both of these factors permit significant savings.
480 Y/277 V, 480 Y/277 Volt
_____________ - is a less common electrical service in large commercial and industrial buildings that is used to power specially designed heavy machinery.
600Y/ 346 Volt, Alternating Current, Three-Phase, Four- Wire System (600Y/346 V AC, 3-4W)
This system is designed like the 480Y/277 V AC, 3-4W described earlier, except that 600V and 346 V are available in the circuit or feeder configurations.
600Y/ 346 Volt, Alternating Current, Three-Phase, Four- Wire System (600Y/346 V AC, 3-4W)
The _____________________ has additional economic advantages from the standpoint of equipment and conductor sizing in comparison to the 208Y/120 V and 480Y/277 V systems. However, the 550 V or 575 V equipment used on the 600Y/346 V system is not as readily available as the 460V equipment used on the 480Y/277 V system. As a result, this electrical service is used primarily in industries where the 600Y/346 V systems area tradition.
600Y/ 346 Volt, Alternating Current, Three-Phase, Four- Wire System (600Y/346 V AC, 3-4W)
There are 240V between the windings of each phase- that is, between Phases X and Y, phases X and Z, or phases Y and Z. Between Phase Y and ground there is 208V available.___________ is known as the high leg or wild leg because it has a higher voltage to ground than the other legs.
240/120 Volt, Alternating Current, Three-Phrase, Four- Wire System (240/120V AC, 3-4W), Phase Y
Is another fairly common electrical service found in commercial and industrial buildings where three-phase motors, above about 1/2 horsepower, and equipment such as large air conditioners are used. On this three phase, four wire, delta connected system, the mid- point of one phase winding is neutral to provide 120 V between phase X and ground and Phase Z and ground only.
240/120 Volt, Alternating Current, Three-Phrase, Four- Wire System (240/120V AC, 3-4W)
_____________________ is the target voltage entering the service panel.
System Voltage
___________ will vary slightly for different buildings because of variations of voltage available at the transformer and voltage drop in the service conductors. The standard for the system voltage is actually _____________.
System Voltage, 120/240 V
______________ - A ___________ occurs as current flows from the service equipment through the branch circuit conductors to the outlet. On a ____________, approximately _________ is available at the outlet of the ____________. Measured voltage at an outlet or connection is called the ________________.
Utilization Voltage, voltage drop, 120/240V, 115/230V, Branch Circuit, line voltage
____________ such as switches, receptacles, relays, and conductors are designed to endure voltages slightly higher than the ____________. The highest voltage to which a wiring can be exposed is known as _________________.
Wiring devices, utilization voltage., maximum voltage.
_____________ is defined as a system or circuit conductor that is intentionally grounded. When something is “_________” in accordance with the National Electrical Code (NEC), it is connected to ground or to a conductive body that extends the grounded connection.
Grounded Conductor, grounded
In a single branch circuits, a ______________ serves as the _____________ of the circuit. It completes the circuit by connecting the ungrounded (hot) conductor to ground. Thus, in circuit design, the ________________ is considered to be a current carrying conductor because it serves as a ______________ to the circuit’s power source.
grounded conductor, grounded leg, grounded conductor, return path
__________ are meant to keep people from getting shocked when using electrical devices or appliances.
Grounded conductors
It keeps the metal of the outlet from getting hot and causing electrical shock.
Grounded conductors
A _______________ performs the function of a grounded conductor for at least two ungrounded (hot) conductors that have sources from different voltage phases, such as on a multiwire branch circuit, multiwire feeder, and the electrical service.
Neutral conductor
It is a grounded conductor that is shared between two or more ungrounded conductors. Thus, a _____________ is frequently called a _____________ or ____________.
Neutral conductor, neutral conductor, shared neutral or common neutral
______________ are also called the _________. Although both the grounded and ungrounded conductors connect to the earth, if an accident occurs like an appliance breaking, you can get _______________ if you come into contact with an ungrounded conductor.
Ungrounded conductors, hot wire, electrocuted
________________ is the practice of dividing loads as evenly as possible between the ungrounded conductors on a multiwire circuit, feeder, or service. A well- designed neutral is balanced so that under under load little or no current flows through the neutral conductor. On a ___________, each ungrounded conductor should carry loads equally.
Load balancing, multiwire circuit
