MIDTERM EXAM (2) Flashcards
3 Ways of illustrating the components of the building electrical Systems
Block Diagram
Single Line Diagram
Riser Diagram
A horizontal single line diagrams of the building’s electrical system from the incoming service to the utilization items at the end of the system where the major electrical components are shown as blocks or rectangles
Block Diagram
A ways of illustrating the components of the building electrical systems that is when electrical symbols are used in lieu of the blocks or it is also called a one line
Single Line Diagram
Is a vertical line diagram of the major electrical components of the buildings electrical system presented showing the spatial relations between components
Riser Diagram
Are materials which allow the free flow of electrons through them. They inherently have a low bond resistance to the free electrons they contain
Conductors
Material for conductors the is preferrable for all types
Copper
Most commonly used material for conductors
Copper and Aluminum
3 types of Conductors
Wires
Cables
Bus Bars
It is an insulated stranded wire
Cord
Are single insulated conductors No. 6 AWG or larger or they may be beyond conductors of any size assembled into a single unit.
Cables
are single insulated conductors No. 8 AWG (American Wire Gauge or smaller, for the English System. It is the B 1 & S Gauge or Brown and Sharpe Gauge. The smallest size of wire permitted is No. 14.
Wires
are range conductors which are not circular in cross sections and usually found only to supply the main switch boards.
Bus Bars
Enumerate the Types of Cables
Armored Cable (Type AC)
Metal Clad Cable (Type MC)
Mineral Insulated Cable (Type MI)
Non-Metallic Sheathed Cable (Type NM or NMC)
Shielded Non-Metallic Sheathed Cable (Type SNM)
Underground Feeder and Branch Circuit Cable (Type UF)
Service Entrance Cable (Type SE or USE)
Power and Control Tray Cable (Type TC)
Flat Cable Assemblies (Type FC)
Flat Conductor Cable (Type FCC)
Medium Voltage Cable (MV)
Enumerate the Types of Insulators
Moisture-& heat-resistant rubber
Thermoplastic
Moisture-resistant thermoplastic
Moisture-& heat-resistant thermoplastic
Moisture-& heat resistant cross-linked thermosetting polyethelene
Silicone-asbestos
Asbestos and Varnished Cambric
5 Purpose of Conduits
- To protect the enclosed conductors from mechanical injury and chemical damage.
- To protect people from shock hazards by providing a grounded enclosure.
- To provide a system ground path.
- To protect the surroundings against fire hazard as a result of overheating or short circuiting of the enclosed conductors.
- To support the conductors
Are circular raceways used to enclose wires and cables and are of metal or plastic (PVC)
Conduits
Enumerate the Types of Steel Conduits
Rigid Steel Conduits
Intermediate Metal Conduit
Electric Metal Tubing
A thin-wall steel conduits
Electric Metal Tubing (EMT)
A type of steel conduits with a thickness of 0.071 mm
Intermediate Metal Conduit
A type of steel conduits with a thickness of 0.117 mm.
Rigid Steel Conduits
Standard length of steel conduits
3 M or 10 ft
Are channels or wiring accessories so designed for holding wires, cables and busbars that are either made of metal, plastic, or any insulating medium.
Raceways
2 types of Raceways
Floor Raceways
Ceiling Raceways
Enumerate the 2 Ceiling Raceways
Header ducts (wireways)
Distribution ducts (laterals)
is a point in the wiring system at which current is taken to supply utilization equipment
Outlets
Enumerate the 3 Floor Raceways
underfloor raceways
cellular metal floor raceways
cellular concrete floor raceways (precast)
It refers only to the box in the wiring device¹ in which the utilization equipment (appliance) cord is plugged into
Receptable
It includes all devices that are normally installed in wall outlets boxes, including receptacles, switches, dimmers, pilot light, attachment plugs and wall plates.
Wiring Device
3 Kinds of Outlet
Convenience Outlet ( Attachment Cap)
Lighting Outlet
Receptacle Outlet
A kind of outlet that is the complete set-up which establishes connection between the conductor of the flexible
Convenience Outlet or Attachment Cap
A kind of outlet that intended for direct connection to a lamp holder, lighting fixture, or pendant cord terminating in a lamp holder.
Lighting Outlet
A kind of outlet where one or more receptacles are installed.
Receptacle Outlet
These are contact devices installed at an outlet for the connection of a single attachment plug. It includes receptacles and their matching cap (plug), wall switches, small dimmers, and outlet box-mounted lamps.
Receptacles
These are devices for making, breaking, or changing connections from electrical circuit under the conditions of load for which they are rated.
Switches
Types of Switch (According to voltage)
250V
400V
5KV
Types of Switch (According to intensity of use)
Normal Duty (ND)
Heavy Duty (HD)
Light Duty (LD)
Types of Switch (According to type of service )
Service Switch
Power Switches
Wiring Switches
General-purpose switches
Three-way switches
Four-way switches
Electrolier or multi-circuit switches
Momentary contact switches
Dimmer switches
It is a resistor for regulating a current by means of variable resistances
Rheostat
Types of Switch (According to number of poles and throws)
Rotary switch
Push-button switch
Toggle or tumbler switch
Enumerate the different special switches
Time Controlled Switches
Remote Control (RC) Switches
Air Switch
Magnetic Switch
Float Switch
Mercury Switch
Key Switch
Automatic Transfer Switch (ATS)
These are covering for switches and wall outlets usually made of metal or of phenolic compound (Bakelite)
Wall Plates or Faceplates
Different Wall Plates
one-gang, two-gang and three-gang
is a device, usually of handle-operated, movable blade and fixed grip, a conductor that control blocks of contacts and shaped copper clips, are forced together to make or break a circuit.
Contractor
It is a small electrically-operated contactor.
Relay
It is a protective glass surrounding an electric outlet or light switch
Fuse plate
are devices whose sole purpose is to protect Insulation , wiring , switches and other apparatus from overheating or burning , due to overloads , to faults or to short circuits , by automatically cutting off the circuit .
Over-current Circuit Protective Devices
It is a device consisting of an alloy link of wire
with a low melting temperature which is inserted in the circuit , in such a way , that all current which passes through the circuit , must also pass through this metal .
Fuse
Types of Fuses
Plug Fuse
Cartridge Fuse
Open Link Fuse
refers to the cutting - off or disconnection of the current electric supply
Tripping
______ refers to the upstream side of a load or device ; or it refers to where the current will come from .The downstream side of the device is called the “ _________ “
Line Side | Load Side
popularly known as “ panel “ or “ electrical panel “
Panelboards
An instrument which responds to the changes in temperature and consists of sensitive elements which expands and contracts according to the degree of heat . The movement may make or break an electric current or may close and open a small port in a compressed air line .
Thermostat
A switch that automatically interrupts an electric circuit to prevent excess current from damaging apparatus in the circuit or from causing a fire .
Circuit Breaker
it is simply the
be disassembled and a new fuse link inserted to replace the one within . box wherein the protective devises are housed from which the circuits and busbars terminate . If the devises are of fuses , it is called a “ __________and if the devices are
circuit breakers , it is called a “ ___________________l .
Panelboards |Fuse Panel| Breaker Panel
A. Nonrenewable plug fuse
B. Nonrenewable knife blade fuse
C. Nonrenewable dual element time delay ferrule cartridge fuses
D. Nonrenewable high interrupting capacity current limiting fuse ( dual element )
E. Nonrenewable miniature fuse
Types of Panel Boards
Lighting Panelboards ( LP )
Power or Motor Panelboards ( PP )
Distribution Panelboards ( DP )
