utilities: chap 1-3

c 1-3 definition of terms

Ion

is the term applied to an atom or molecule which is not electrically balanced. It is an atom or molecule that is electrically charged. It simply mean there is a loss or gain of one or more electrons.

Ampere

is the standard unit used in. measuring the strength of an electric current

voltage

-is the electrical pressure that causes the electrons to move through a conductor (wire). In other words, this is the electromotive force.

Alessandro Volta

Volt was named after ________, an Italian scientist who discovered that electrons flow when ·two different metals are connected· by a wire ·and then dipped into. a liquid that connduct or carry electrons

Andre M. Ampere

Ampere is named after who?

Watt

is the rate or measure of power used or consumed. It represents the equivalent heat volts and ampere consumed by lights, appliances or motors.

James Watt

The term Watt ·is. named after a Scottish inventor who is he?

Circuit

refers to the wire installations that supply current to light and convenient outlets.

Resistance

is the friction or opposition to the flow of current by the wires and transformers, analogous to plumbing installation, where the flow of water is subjected to resistance caused by friction between the water. and the inside wall of the pipe, and the various form of turns and fittings.

Composition of the Conductor:
Length of Wire.
Cross Sectional Area of Wire.
Temperature

4 Factors that Influences Conductor Resistance.

Composition of the Conductor:

this refers to a conductor having free electrons that has low resistance.

Length of Wire.

The Ionger the wire, the higher is the reSistance.

Cross Sectional Area of Wire.

The bigger the cross sectional area of wire, the lower its resistance.

Temperature

Metal offers high resistance to high temperature (heat).

Electric Current

is the flow or rate of flow of electric force in a conductor.

1. Source of voltage
2; A closed loop of wiring
3. An electric load, ,
4. A means of opening and closing the circuit

A current will only flow if a circuit is formed comprising a complete loop and contains all the following required components. what are the 4 ?

l. Direct Current (DC) .
2. Alternating Current (A C)

Electric Current is Classified as:

Direct Current

This electricity, flows in one direction. The flow. is said to· be ·from negative to positive.

Alternating· Current

This electricity constantly reverses its direction of flow. It is generated by machine called generator. This type of current is universally accepted because of its unlimited number of applications.

Alternating Current or Voltage

is a current or voltage that changes in strength according to a sine curve.

a) .Electron
b) Proton.
c) Neutron

Electricity. is a ·property · of the basic particles· of matter which like an atom, consists of:

Electron

is the negatively charged particle of an Atom sometimes referred to as the negative charge of electricity

Neutron

is that particle of an Atom which is not electrically charged ·and weighs slightly more than the proton

Proton

is th positively Charged particle of an Atom which is sometimes referred to as the positiye Charge of electricity that weighs about 1850 times as much as the Electron.

Impedance

electrical term for friction

The parallel circuit

is sometimes· referred to· as multiple connections where the loads are placed across the same voltage constituting a separate circuit.

Series Connection

a single path exist for current flow, that ·is, the elements are arranged in a series one after the other with no branches.

Transformer

is a simple static device consisting of a magnetic core wherein the primary and secondary windings are made.

Power

is the rate at which energy is used or alternatively; the rate at which work is done

Work

is the product of Power and Time

Energy

ln electrical terms, it is synonymous with Fuel. It is associated with work. It can be expressed in gallons, liters. barrels or tons of oil, coal, kilowatt hour or consumed· electricity arid cost of operations.

Electric Conductors

are substances or materials used to convey or allow flow of electric current·

Insulators

are substances or materials that resist the flow of electric current

Wires

are those etectrical conductors 8 mm~ (AWG No. 8) and smaller in sizes.-

Cables

are those which are larger than the wires

Stranded Wire

consists of a group of wires twisted to form a metallic string.

Cord

is the term given to an insulated stranded Wire.

mil

The word ______ that is equal to 1/1000 of an inch was used to describe. or measure ·a round wire diameter

Armored Cable (AC)

is a fabricated assembly. of insulated conductOrs enclosed in flexible metal sheath. It is. used both on exposed and concealed work

Metal Clad Cable (MC)

is a. factory assembled cable of one or· more conductors each ·individually insulated and enclosed in a metallic sheath of interlocking tape of a. smooth or corrugated tube: This type of cable is especally used for service feeders, branch circuit, and for indoor Or outdoor work

Mineral lnsulated Cable (MI)

is a factory assembly of one or more conductors insulated with a highly compressed refractory mineral insulation enclosed in a liquid and gas tight continuous copper sheath

Ampacity

is defined as the ability of the Wire or conductor to carry current without overheating ..

Raceways

are channels 'or wiring 'accessories designed for. holding ·wires, cables· or busbars that are· either made of metal, plastic, or any insulating mediums.

Conduit pipe

'is· the most common electrical ·raceways ·used in all types of construction.

Connector

is a metal sleeve usually made of copper that is slipped over and secured to the butted ends of conductors in making a joint. It is otherwise called splicing sleeve.

outlet

is a point in the wiring system at which current is taken to supply utilization equipment.

Convenience outlet or attachment cap

is· a device that by insertion into a receptacle establishes connection between the conductor of the. flexible cord and the conductors connected permanently to the receptacle.

plug

is another name for the attachment cap on the wire coming from a device such lamps or appliances.

Lighting Outlet

is an outlet intened for direct connection to a lamp holder, lighting fixture, or a pendant cord, terminating. in a lamp holder.

Receptacle Outlet

is an outlet where one or more receptacles are installed.

Junction Box

is not an outlet. By definition, it does not supply current to utilization device.

Pull Box

is a box with a blank cover that is inserted in one or more runs or ·raceways to facilitate pulling-in the conductors. It may also serve to distribute the conductors.

Receptacle

are contact device installed at the outlet for the connection of a single attachment plug.

Switch

is a device that opens or closes the circuitry in an electric circuit. ·

Branch Circuit

is defined by the National Electrical COde (NEC) as: "the circuit conductors .between the final over current protective device and the outlets."

Flexibility of the Circuit

means that the installation can accommodate all probable pattern arrangements and location of the loads for expansion, or future development.

Reliability and Efficiency of Service

means to have a continuous service and supply of power that are all dependent on the wiring system

Safety

means that independent service can be used in lieu of emergency equipment as backup for. normal services.

Fuse

is· defined aS an overall current protective device with a circuit opening fusible element which opens (break) when there is an over current in the circuit

Circuit Breaker

is an over-current protective device designed to function as a switch. Basically, it is equipped with an automatic tripping device to protect the branch circuit from overload and ground fault.

Trip or Tripping

refers to the cutting-off or disconnection of the current supply

Panel board

is simply the box wherein the protective devices are grouped from which they are fed.