Power Distribution and transmission
AWG
Also knowmm system used since 1857 predominantly in the United States and Canada for the diameters of round, solid, nonferrous, electrically conducting wire.
30 AMPS (10 G)
Appliances it e.g. Dryer, Air-conditioning, Water Heater
20 AMPS (12 G)
Appliances like Laundry, Bathroom & Kitchen Circuit
SINGLE CONDUCTOR WIRES
Are THW and THWN/THHN, which are protected by metal or plastic sheathing.
red wires
Are also used for hot wires, switch legs (like to a ceiling fan), and are the second hot wire in 220-volt installations. Another useful application is the interconnect wire between two hardwired smoke detectors.
BLACK WIRES
Are always used for hot wires. These wires may feed a switch or outlet and are often used as switch legs.
WIRES
Are those electrical conductors which are 8 mm²
Electrical grid or simply grid
Distribution takes place through a system known as the _______ which is designed to keep power constantly on call so that it can meet demand. Power grid distribution lines can be above or underground.
CABLES
Electrical conductors greater than 8 mm²
* COMPOSITION OF THE CONDUCTOR * LENGTH OF THE CONDUCTOR *CROSS SECTION AREA OF THE CONDUCTOR *TEMPERATURE
FACTORS WHICH INFLUENCE RESISTANCE OF THE CONDUCTOR
NONMETALIC SHEATHED CABLE
Factory assembled two or more insulated ——Solid i, . §i Copper conductors having a moisture resistant, flame retardant and non metallic material outer sheath.
40 AMPS (8 G)
Feeder & Large Appliance Wire
55 AMPS (6 G)
Feeder & Large Appliance Wire
* SILVER * COPPER * ALUMINUM * NICKEL * BRASS * ZINC * PLATINUM * IRON * LEAD * TIN
GOOD CONDUCTORS:
* RUBBER * PORCELAIN * VARNISH * SLATE * GLASS * MICA * LATEX * ASBESTOS * THERMOPLASTIC * OILS * WAX
GOOD INSULATORS:
15 AMPS (14 G)
General Lighting, Fans & Outlet / Receptacle Circuits
True
In almost all cases, the power plant consists of a spinning electrical generator.
WHITE AND GRAY WIRES
Indicate a neutral wire
neutral wires
Indicate a neutral wire
SERVICE ENTRANCE CABLE
Is a single conductor or multiconductor assembly provided with or without an overall covering.
resistance
Is done by the friction between the flow of current and the conductor or insulator.
MULTI CONDUCTOR WIRES
Is made from metal or plastic and contains a neutral wire, a "hot" wire (or two), and a grounding wire.
Service Entrance
Is that portion that runs from the utility lines to the point of attachment at the waterhead, then down an entrance cable or conduit to the meter.
CORD
Is the term given to a heavily insulated wire
ELECTRICAL WIRE
It is made of a metal that easily conducts electricity, usually copper, in a plastic sheath called an insulator.
Electrical conduit
Made of Plastic, metal, fiber or fired clay and is available for special purposes
true
Metals offers high resistance to high temperature
<1000V
Minimum Clearance Requirement
conductors
Most metals are considered to be good _____ of electrical current.
gray green
Neutral wires are _____, grounding wires are _____, and hot wires are any other color.
SERVICE ENTRANCE CABLE
Primarily used for services and of the types se and use.
100 AMPS (3 G)
Service Entrance & Feeder Wire - To Panel Box
150 AMPS (1/10 G)
Service Entrance & Feeder Wire - To Panel Box
200 AMPS (3/10 G)
Service Entrance - From Utility Pole to Energy Meter
True
T or F. A good conductor must have extremely low resistance
True
T or F. a good insulator must also have extremely high resistance.
resistance
The longer the wire, the bigger the _____
good conductor
The mineral composition of a conductor is essential factor in determining a ______.
MULTI CONDUCTOR WIRES
The wires are color-coded to guard against connection errors.
SINGLE CONDUCTOR WIRES
The wires themselves can be either solid or stranded. Solid-core wire produces the best connections, but its stiffness makes it more difficult than stranded wire to route through conduit.
Blue and yellow
These wires are usually pulled in conduit.
blue
They also are used as switch legs to things like lights and fans.
Insulators
They do not let electrons flow very easily from one atom to another. Insulators are materials whose atoms have tightly bound electrons.
HH
This wire can withstand heat up to 194 degrees Fahrenheit.
GREEN WIRES
Wires are used only for grounding. These wires will ground devices and shall be bonded to junction boxes and appliance connections for safety.
yellow
are generally used for switch legs. These control things like light, fans, and switched outlets.
blue
are generally used for travelers in three-way and four-way switch applications
Insulators
are materials that have just the opposite effect on the flow of electrons.
3.0 m (10ft)
at the electrical service entrance to buildings, also at the lowest point of the drip loop of the building electrical entrance, and above areas or sidewalks accessible only to pedestrians, measured from final grade or other accessible surface only for overhead service conductors supported on and cabled together with a grounded bare messenger where the voltage does not exceed 150 volts to ground
copper
considered to be a conductor because it "conducts" the electron current or flow of electrons fairly easily. It is just one of the more popular materials that is used for conductors.
AMPACITY
defined as the ability of conductor to carry without over heating
Electrical conduit
electrical piping system used for production and routing of electrical wiring
ARMORED CABLE
fabricated assembly of insulated conductors enclosed in flexible metal sheath. Armored cable is used both in exposed and concealed work.
N
for the nylon coating that covers the wire insulation.
4.5 m (15ft)
for those areas listed in the 3.7 m (12 ft) classification where the voltage exceeds 300 volts to ground
Power distribution
is a process which is used to move electricity from locations where it is generated to people who need it.
W
means that the wire is approved for damp and wet locations. This wire is also suitable for dry locations.
HH
means that the wire is heat resistant and can withstand a higher temperature
X
means the cable is made of a synthetic polymer that is flame-retardant.
H
means the wire is heat resistant.
5.5 m (18ft)
over public streets, alleys, roads, parking areas subject to truck traffic, driveways on other than residential property, and other land such as cultivated, grazing, forest, and orchard
3.7 m (12ft)
over residential property and driveways, and those commercial areas not subject to truck traffic where the voltage does not exceed 300 volts to ground
7.5 m (24.5ft)
over tracks of railroads
Transmission lines
run between sub stations. They are higher and carry high voltages.
Distribution lines
run from the substation to the end user location
MC armored cable
sheathed in spiral metal, but because of its expense it is not commonly used for interior applications.
T
stands for thermoplastic insulated cable.
thermoplastic material
the neutral and hot wires are insulated by a ____
Substations
transform voltage from high to low or low to high.
NONMETALIC SHEATHED CABLE
used specifically for one or two family dwellings not exceeding 3- storey bldg
Service Entrance
where the electric utility's maintenance responsibility ends and the building owner's responsibility begins
ELECTRICAL WIRE
|s the medium through which electricity is carried to and through each individual home that uses electrical power.