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What is 3-phase electric/ Power transmission from generator to end user

Additional links: How to wire 3-phase
 How to wire single phase
power generation

Power Generation Book

Co-generation is growing market as demand for reliable energy grows.
Book by Singh covers the basics, and the engineering math. Future business and industry leaders should be aware of the complexity and variability of electricity.

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Basic How to wire 3-phase with illustrations and .pdf resources

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Water heater formulas/ pdf
Water heater formulas 2/ pdf
Troubleshot household electricity
What is 3-phase
See inside household electricity
Basic home electricity
Figure volts amps watts
3-phase electric Power company generates 3 phase electricity
and transmits electricity across high voltage lines....
Steam turbine, gas engine, wind or water rotates magnet past coils of wire, generating AC or alternating-current electricity.
Solar panel arrays produce DC or direct-current electricity that must be converted into AC before being transmitted on the same electric lines used by AC. Co-generation can be added at any point along the line, including end user generator, solar panel array or windmill.
generatorSteam turbine or gas engine rotates magnet past coils of wire. This is an AC alternating current generator
Although it's unknown exactly what electricity is, it can be described as movement of electrons. A basic principle of electromagnetism is that moving a magnet across a coil of wire causes electrons to move along the wire. This is called electromagnet induction. A 3-phase generator uses this principle by rotating a magnet past 3 separate stationary coils. In the US and Americas, the generator rotates 60 times per second (called 60 hertz or 60 cycles). In Europe, Asia, Africa etc, the grid is 50 cycles. Appliances and timers made for 60Hz might not function with 50 Hz etc, while some devices are rated 50-60Hz and will work worldwide.

Each time the magnet rotates past a coil, it produces a pulse of electricity that moves electrons down the wire. The pulses of electricity reverse direction each time the N and S poles of magnet pass, creating what is called alternating current.
Because the magnet passes the coils at different times in the rotation, each pulse of electricity is out-of-phase with the other. The result is a three phase wave of electricity that is transmitted from the generator across 3 separate wires. The entire grid is energized with current that oscillates at 60 cycles per second, with electrons racing back and forth on the wires, accelerating one direction and then back again 60 times per second. 

Small generators, sold at the local store, are different than power plant generator. Small generators produce two-wire single-phase alternating current by rotating a coil of wire, located in center of generator, past two steel magnets located on outer edge of generator.
Large generators found in a power plant have a different design, as shown in illustration on left: the three coils are on the outer edge, and a large electromagnet is located in center. Paradoxically, it requires so much electricity for the electromagnet that the power plant can consume up to 25% of total output. Each power plant is connected to other power plants so if one shuts down, it can be started again using electricity from another plant.
So how did they get enough electricity to start the first power plant generator? Answer: Using smaller and smaller generators until a small generator with coil on inside and magnets on outer edge started it all. The ordinary magnet is the root of AC electricity.
Read about generators
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You can hear the rise and fall of voltage by turning on a buzzer. The buzz is caused by the rapid rise and fall of voltage on the wire.
3 oscillating pulses of electricity leave generator
Understanding electricity is mathematical. Illustration on left shows the voltage of 3-phase alternating current over time. Three phase has 3 wires, and each wire is 1/3 cycle behind the other caused by the generator magnet hitting 3 different coils at different times during the rotation.  As the north pole of the magnet gets closer to the coil, the voltage climbs, until it reaches peak just as the magnet arrives, and then voltage declines as magnet moves away. Voltage drops to zero on the coil when both south and north are equidistant away from the coil, and then voltage begins to rise on the coil again as the south pole gets closer. Alternating current means the electrons reverse direction along the power line each time the south and north magnets pass the coil, with north electrons going one direction until voltage drops to zero, and then rise again as the south pole pushes electrons the other direction.
Why use 3-phase? Three phase means more power with less heat loss from amps, making it more efficient and less expensive compared with single phase. Since 3-phase has 3 coils and 3 wires coming off the generator, you get a voltage curve that looks like the illustration on the left... showing the rise and fall of voltage on each wire as the magnet rotates. Since there are 3 wires connected to the 3-phase motor, the motor receives average voltage that never falls to zero, resulting in higher average voltage, which means lower amps on the wire, so a smaller wire can be used. "In a balanced 3-phase system, the wires can be about 75% the size of conductors (wires) for a single-phase two-wire system of the same KVA rating. This helps offset cost of supplying the third wire required by 3-phase systems."
"The horsepower rating of three-phase motors is about 150% greater than for single-phase motors with a similar frame size. The power delivered by a single-phase system pulsates, and the power falls to zero three times during each cycle. The power delivered by a three-phase circuit pulsates also, but it never falls to zero. In a three-phase system, the power delivered to the load is the same at any instant. This produces superior operating characteristics for three-phase motors."  
3-phase circuits and basic math .pdf.      Read about 3-phase water heaters    Read about single-phase
Generator and turbine Generator and turbine
Illustration shows Typical turbine used in coal-fired power plant.
High pressure steam explosion accelerates turbine.
Coal or gas or nuclear rods boil water into steam.
High pressure steam explosion accelerates turbine.
Turbine rotates generator.
Backup diesel generators and Gas engines can also produce electricity without steam, using water to cool engine.
Generators in US rotate at 60 cycles per second
Output is 3-phase 60 Hz electricity
See illustration of coal-fired plant
Web link
generatorLarger image
WYE generator/ line and phase voltages
The end of the wires on each coil is joined together forming the Neutral wire, and this means the coils are in parallel instead of series, so this is a WYE generator.
Power is transmitted over 3 Hot  wires or Line wires that are accompanied by the Neutral wire. The Neutral wire is always bonded to the ground wire at the plant, switchyard and every pole along the way.
Line voltage: Each line carries same voltage if generator is functioning. Voltage from line1 to line2 is same as line1 to line3 is same as line2 to line3.
Phase voltage is measured between any Line and the Neutral.
Phase voltage is calculated by formula: Line voltage √3 (1.732) = Phase voltage.

Generator can be powered by steam explosion, back up diesel engine, natural gas, wind or falling water etc.
Center coil is electro-magnet with north and south pole.
The center coil rotates
Three identical stationary coils are located inside the generator, each at exactly 120 angle from each other.
Each of the 3 coils is connected to the Neutral wire that is connected to all 3 coils.
One hot wire comes off each coil... line 1, line 2, and line 3... these wires become the 3-phase output along transmission lines.
Small single-phase generators are different. They use a magnet, and the coil rotates in the center between the magnets.
Small generators can be used to provide electricity to larger and larger generators, until there is enough voltage to magnetize the center coil of a power plant generator.
As much as 25% of the electricity generated by a power plant can be consumed by the center coils of power plant generators.
If all the generators go out, then electricity must be brought in from other power plants to get started again.
Illustration shows coil 1-2-3 wired in parallel, or a WYE configuration.
WA Parrish coal-fired power plant
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WA Parrish coal-fired power plant
Water is boiled until it explodes into steam
With Smither's Lake in foreground. Located outside Houston Texas
Water is pumped from Brazos River to fill lake. Pump is located in Rosenberg, several miles away, at a sharp bend in the River where the channel runs deep.
Water is key for electric power generation. No water, no electricity.
During drought years, water for power plant has priority. No water is available for rice farmers. Rice fields sit fallow or are converted to other dry-farm crops such as cotton.
See illustration of coal-fired plant
Smither's Lake is man-made lake. Water is used to cool parts and run turbine.
Some of the water is recycled, while other water is not.
Coal trains arrive from Wyoming and dump coal
Bulldozers move coal into piles that feed into conveyors
Coal is burned
Water is heated into steam
Water turning into steam releases massive amount of energy called steam explosion
Steam explosion accelerates turbine
Turbine rotates generator at 60 cycles per second
Electricity leaves power plant
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Transmission substation or switchyard is located at power plant

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Electricity leaves power plant
Generator produces high-amperage 30,000 volt AC electricity.
It is not economical to transmit high-amperage electricity because wires must be larger, towers moved closer, larger insulators, heavier switchgear, and more heat loss... causing greater expense and shorter transmission distance.

To solve problem of high amperage, electricity from generator is sent to Transmission Substation or Switchyard located at power plant.
Switchyard uses Step-Up transformers to raise voltage and reduce amperage.
Volts x amps = watts is basic formula: When volts are increased, then amps are decreased.
Step up transformer decreases Amperage, while Voltage is increased.
So high voltage, low amperage electricity leaves power station on transmission towers, ranging from 69,000 volts upwards.
Lower amperage means less heat loss during transmission.

Electric power distribution system operation 1990/ pdf
Power lines leave power plant
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Other large image
Another image
Many power lines leave power plant
Large towers might carry 500 Kv or 500,000 volts
Shorter wooden towers might carry 115 Kv to 230 Kv
Wide corridor of land is needed for power lines leaving WA Parrish power plant en route to Houston and surrounding areas

This group of wires is headed to Houston/ Harris Co and Fort Bend Co on a wide corridor of land.
Other towers leave power plant and go different directions.
Use Google Earth to view local power station, and trace wires to local sub-stations. And then follow wires into each town and neighborhood, and to more substations to end user

Electricity is a wave that travels at the speed of light.
If AC electricity is not consumed at moment when available, it is wasted. Unless the AC is converted to DC and stored in a battery.
Cell phone and laptop batteries store AC power.
Electric water heater is indirect way to store electric power. Water stays hot in tank for many hours after power is off.
Transmission tower
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Tower carries 3 hot wires run in pairs
This tower has 12 hot wires, plus 2 system neutral wires located at top of tower.
The number of hot wires on tower can be divided evenly by 3, since tower is transmitting 3-phase power
Groups of three wires leave power plant substation attached to transmission towers
Example tower on left has 12 Hot wires plus 2 Neutral wires at very top. Each transmission tower and pole are grounded

Transmission wires run in pairs. Both carry same phase hot and are separated by wire tie. Tower has 6 pairs of wires

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Transmission groundEach tower is grounded at base of tower on all 4 legs
Transmission tower ground wire
Each tower and pole is grounded at base of pole or tower.
4-legged tower will have ground at each leg.
Each type of soil presents different resistance to ground. Low resistance is best since it will conduct electrical short or lightning strike best. Moist clay soils and salty soils offer less resistance to ground.... the ground rod is driven deep enough to reach permanent dampness. Dry rocky or sandy soils have higher resistance to ground and may require more ground rods in parallel, or an array of parallel ground rods, or a continuous ground cable that connects multiple towers together. Frozen soils are non-conductive and offer greatest resistance to ground. Formulas and measurements are used to determine the type of grounding that is necessary.
Ground wire increases reliability of grid, preventing excessive voltage peaks during disturbances.
System neutral wires at top of tower connect to smaller ground wire that runs to ground connection at base of each tower. Neutral wires are generally larger than ground wires.
Depth of ground connection into soil is determined by type and conductivity of local soils and standard electric practice. Dry, loose and rocky soils are less conductive than fine-grain wet compact soils, high salt content of soil increases ground conductivity etc... so each region must be assessed for proper grounding method based on soil testing and established formulas. Array of ground rods increases grounding and resistance to surge caused by lightning etc.
subtransmission towerLarger image
System neutral/ or static wire
System neutral wire is present on each pole and tower throughout transmission, sub transmission and distribution.
System neutral- ground array is used to stabilize the grid. Neutral and ground are established at each substation, and at each pole and at final user location. For example each home and business has a ground rod. Each pole carries a neutral that is bonded to the ground rod located at base of pole.
Neutral is important for grounding and for 3-phase transformer configurations, and single-phase household power.
System neutral is connected to ground wire at each tower and pole throughout grid.
The neutral wire connects all ground wires together into one giant array across the grid.
The neutral wire, when at top, acts like a shield against lightning strike, called a static wire
Air is a good insulator. As a result, the electrical charge carried in storm clouds cannot easily equalize itself with the ground.
Electricity is the flow of electrons from unequally charged materials. Insulators like breathable-air stop the flow of electrons until the charge becomes great enough to overcome the insulation. All electricity wants to find route to ground to equalize the electric charge. When overhead storm clouds carry a charge, the electrons in the clouds are not equal to the charge on the ground below. The result is a buildup of charge to the point where the flow of electrons will pass through the insulation provided by air. When that happen, there is a lightning bolt. The lightning will often strike highest point like a tree, house on hilltop, or transmission tower. =The static wire or system neutral is directly grounded with a ground wire, or series of ground wires, at each tower or pole. This ground wire gives the lightning an easy route to ground thus reducing damage caused by lightning.
If the lightning carries more voltage than the ground wire can absorb, there is a flashover onto the power wires, or hot wires. The flashover causes relays to activate and shut down the line.
An OPTICAL GROUND WIRE is a static wire with fiber optic cables embedded in the core for use as a communications path. 
Power transmission lines
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Transmission towers located in Sugarland Texas
Located near W. A. Parrish generating station in Thompsons Texas

Electricity arose from advancements in all sciences across many centuries.
Each advancement was supported by climate, food production, governments, education, writing, printing, and increasing population.
It took millions of hours to invent electricity.
Today, it takes millions of hours each year to produce, manage and maintain electric power.
Imagine the number of labor-hours needed to cut grass along transmission corridors.
Power companies are finding ways to re-purpose transmission corridors into commercial and recreational areas without endangering the electric grid.
Insulated standoff Insulated stand-offs prevent electrifying tower
Each transmission wire must be insulated away from tower or pole
Transmission wires are bare
Wires cannot come into contact with poles or trees, or else electricity will short to ground, causing possible fire and tripped fuse, loud crack sound like lightning
Larger-longer insulators indicate higher voltage
Puller Pulling new overhead cable
New wire is added
Trucks and linesmen are needed to pull new wire from pole to pole
As electric consumption increases, more wire is added
Diameter of wire and material used for wire is based on voltage and cost vrs transmission loss
Pulling electric wire/ photos
Identify power pole parts
pulling new wire
Pulling electric wire/ photos
Wires arrive at distribution substation
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Wires from power plant arrive at Distribution Substation
Wires leave power plant and travel to distribution substations
Distribution substations can be located by following power lines
Wires from one distribution substation also travel to other substations
Follow wire using google earth to see complexity of distribution

Substations generally re-distribute power onto many smaller poles going several directions
The smaller poles have lower voltage than incoming towers

Smaller power co-generating stations are located alongside transmission lines to boost power during peak demand.
Small natural gas-powered generation stations can be brought online quickly to meet demand.
Water for small generation plants can be from water wells

Co-generation is the fastest growing segment of electric generation. Many feel that small co-generation plants will meet demand for future electricity. The capitalist system requires growth to avoid recession and depression. Co-generation plants strategically placed can ensure essential industries receive power, while other less essential areas experience electric shortage.
Distribution Substation
Larger image of substation
Distribution Substation
Example shows substation fed by wires from power plant.
Substation might receive 500,000 volts from generator.
The substation reduces voltage and sends out on several lower-voltage lines.

With new growth, new substations must be added.
electric substation
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Full image
3-phase connects to Distribution Substation
Electricity from power plant to distribution substation
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Electricity from power plant to distribution substation
Illustration shows general concept 1) power-plant, 2) power plant substation with step-up transformers, 3) 500 Kv 3-phase power traveling along transmission towers, 4) 3-phase power arriving at distribution substation with step-down transformers, 5) 69Kv 3-phase power leaving substation on wood poles going to local businesses and homes.
Voltages vary.

Groups of three Hot wires arrive at distribution substation
Substation is for illustrative purpose and does not show all connections or activity

High amperage is bad for transmission because of heat loss, but high amperage is needed by end user
Very high voltage is good for transmission, but lower voltage is good for end user
Transformers solve the amperage-voltage problem
There is inverse relationship between volts and amps
Basic electric formula is Volts x Amps = Watts. Volts and Amps are inversely proportional.
When voltage is reduced, amperage is increased. The reverse is also true.
Electric company can use step-down transformers that reduce voltage and raise amperage. High amperage is needed at each business and home.
Electric company can use step-up transformers that increase voltage and lower amperage. Lower amperage means less heat on the wire, and is good for long-distance transmission.
Step up and step down transformers can be used anywhere as needed
Electric power distribution system operation 1990/ pdf
Power lines leave substation
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Many poles leave substation, traveling to each business and neighborhood
Wires from substation branch off many directions on many wooden poles, sending power all directions
Power can travel many miles from substation to local towns, or substation can be located near town, or near neighborhoods etc

Power poles shown image on left travel to local neighborhoods and businesses.

Follow power lines using google earth to reveal complexity of distribution network
Usually poles leaving substation carry several groups of 3-wires
Poles are generally wood, but can be steel. Voltages vary by type of tower, pole, and height from ground
Example wood pole might carry 115 Kv or 115,000 volts, while steel tower might carry 230 Kv or 230,000 volts or more
Each pole has ground wire running down pole and into the ground
Power lines leave substation
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These power poles go to another substation
Other poles leave substation, traveling to other substations
The line of poles seen in photo on left, leave substation pictured above.
The line of poles travel 15 miles to another substation, and then on to another substation.
Secondary substations also feed local lines.

This power line also feeds another substation which has step-down transformers.
At this point, the transformers increase voltage and lower the amperage, and then the power is again transmitted on tall steel towers to yet another substation with step-down transformers for local power consumption.
ground wire            Ground wire
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ground rod
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Each pole has ground wire
Ground wire is normally smaller than wires that carry power.
Grounding increases reliability of service.
Ground prevents excessive voltage peaks, provides ground connection for system neutral, and discharge path for surge arrestors.
Ground protects people who work on and use electricity.
Proper grounding helps mitigate damage from lightning.
Without a ground wire, overvoltages and other disturbances damage equipment at substation and end user.
Substations generally have multiple grounds to overcome resistivity of soil.
Soils that are warm, tightly grained, wet, and have high levels of dissolved salt offer less resistance to ground.
Loose, coarse, freezing, dry soils with gravel and low salt content offer more resistance to ground.
High pressure means less ground resistance.
Different regions have different grounding specifications.
Why you need ground wire in home
3 phase power lines
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Another image
3 phase arrives at local business
3 wires arrive at business

3 Hot power lines 1-2-3 on pole
Lines travel down street from pole to pole.
Drop lines from each Hot wire sends power to transformers: a-b-c
3-phase power
Larger image with more detailed labeling
There are many different transformer configurations used to make different voltages
Each installation follows same general pattern
3-phase power
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Transformer wiring
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Original image
Transformer wiring/ how to identify transformer wiring
Image shows Delta Primary and 4-wire WYE Secondary
Primary is Delta: How do we know? Each hot wire connects to two transformers.... so they are wired in series
Secondary is WYE. One wire connects to all three transformers, and to Neutral. One wire from each transformer is Hot... so they are wired in parallel
System neutral connects to Neutral and ground
There are many different transformer configurations

This is 'most common type of wiring' because Delta has lower amps/ meaning less heat, so insulation on primary coil is less expensive.

Transformers can be wired different ways depending on the incoming electric supply and end user need.
Two key factors for the grid are economic performance and reliability.
Reliability is necessary because electricity must run clean without big-voltage spikes and low-voltage brownouts. Otherwise motors and HVAC equipment will have shorter lifespan.

Transformer configurations
Transformer manuals
Identify more illustrations of transformer wirings
3 phase surge suppression
Larger image
Capacitor bank on 3-phase distribution line
This 3-phase line is 7200 volts and supplies power to multiple neighborhoods, including my neighborhood
These lines also supply power to several businesses that use motors
With several motors or inductive loads on the line, it will reduce power factor on the line.
Transformers without load also create reduced power factor.

Inductive loads such as motors, contactor coils, relays.... consume large amounts of amperage before voltage during start up ... causing voltage to lag behind amperage.
Resistive loads such as lights and heaters...  consume voltage and amperage at same time, without lag.
Capacitor banks help solve problems caused by voltage lag.

This protects motors of all kinds from surge, including the motors at local businesses, and homeowner appliances and HVAC unit.

Neutral wire at top of pole not shown.

Read about surge suppression for residential and commercial
3 phase service
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Different image
Example 3 phase service
Drop wires connect to insulators, and then loop into weatherhead, and down conduit mast into meter box
Image on left shows Meter box, 3-phase Meter, and breaker box
The box might contain cut off breaker, and not be the final breaker box

Wires drop down conduit mast and enter meter box.
There are many different services, and voltages, and wiring can vary to meet code.
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Example 3 phase service
3 phase weatherhead
Example 3 phase weatherhead
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Example 3 phase service
Showing secondary service wires, service rack with 4 insulators, weatherhead, and service conduit
3-phase arrives at building
Difference between single-phase and 3-phase
What is 208 volt
What is 277 volt
3-phase meter 3-phase meter has 7 prongs
3 Phase meters have 7 prongs that stab into meter box
Unlike household meter that has 4 prongs
3-phase meter
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3-phase meter box

Delta and Wye transformer configurations are wired same.
Illustration on left shows typical 3-phase meter wiring.
In the case of high-leg delta, the wild leg or high-leg connects to top right or Line 3 in illustration.
High-leg delta is a specific transformer configuration ... each hot wire is called a leg.
With high leg delta, the wild leg connects to top right terminal so it's location is identified since this wire carries different voltage potentials than other legs.

Ground wire connects to same terminal where neutral connects
Ground wire cannot be used as neutral, since ground wire is usually smaller gauge than neutral wire.
Neutral wire is same gauge as hot wires so it can safely carry same voltage as each hot wire.
3-phase service panel 3-phase service panel/ Neutral and Ground not shown
3-phase Power passes through a 3-phase electric meter that registers electric usage for billing.
From the meter, power enters a panel box, and connects to 3-pole  main breaker
3-pole means there are 3 places for wires to connect. And each pole is electrically separated from other poles.

Main breaker feeds each hot wire to separate hot busbar.
So there are 3 Hot busbars, each electrically separated from the other, and each carries power from one Hot wire
3-pole circuit breakers snap down over all 3 busbars, drawing power from each busbar, and then 3 wires leave breaker and go to motor switch, or other use etc.

How to wire 3-phase electric
See wiring for 3-phase non-balanced water heater
Example shows timer controlling 3-phase load

Illustration shows typical use for 3-phase.
3-phase load receives 3 hot wires and a neutral.
All single-phase circuits require 2 wires, while 3-phase requires 3 wires. The manufacturer and engineer design electrical equipment to meet the requirement for each application.
Note, the timer is ordinary 240 volt single phase, which shows that single phase 2-wire applications can be achieved by drawing two hot wires from the 3-phase.
It is also possible to achieve 120 volt single phase by drawing 1 hot from 3-phase and using the neutral (applies to 208volt 3-phase or high-leg services or buck-boost transformer)

How to wire 3-phase timers
How to wire T100 series Intermatic timers
Buck boost transformers
How to wire 3-phase
power plant to house electricity
Larger image
Read about basic household electric
Converting 3-phase to single-phase household power
One Hot wire is taken from 3-phase power lines
The system neutral and 1 Hot wire are used to make single-phase power
Residential single-phase power
Basic household electric wiring
Troubleshoot household electric

Power plant to house
Illustration shows 500 KV 3-phase transmission system from power plant to distribution substation > then shows 69 Kv 3-phase sub-transmission system to secondary substation > then shows 7.2 Kv 3-phase distribution system that supplies local area > then shows single-phase distribution system drawn from 1 hot wire on 3-phase that goes to transformer at individual home.
Voltage and amperage are inversely proportional.
Volts x amps = watts.
When volts are reduced at at substation transformer, amps are increased.
High amps are needed at the end user, because amps are the heat that does the work.
However high amps cause heat loss during transmission.
That's why transformer substations are needed: because they control volts and amps.
Each time voltage is reduced, the amperage is increased... and higher amps mean transmission distance is reduced.
So the 500,000 volt lines are used to distribute power long distance.
69,000 volt lines are used for shorter distances.
7,200 volt for local distribution.
Below 4000 volts, the distribution is inefficient because of heat loss

Generally, in the US, each home has a transformer that converts 7200 volt Hot and Neutral into split phase 120-240 volt service.
The home receive low voltage, high amperage
Each home has a transformer that converts 7200 volts into 120-240 single or split phase electricity
Sometimes more than 1 home will share a transformer... result is dimmed lights, or voltage drop each time heavy equipment such as HVAC turns on.


Transformers can convert electricity many ways.

Transformer manuals
Transforming electricity is limited only by physics governing natural world.
For example using a transformer, high voltage and low amperage can be converted to lower voltage and higher amperage used inside each home. There is inverse relationship between volts and amps shown in following formula: Volts x amps = watts.
See electrical formulas

High voltage 3-phase from the power plant can be converted into many different 3-phase voltages depending on which transformer is used. Read about Delta and Wye
The reverse is also possible: Using a transformer, single phase residential power can be converted into certain types of 3-phase.

Since solar generated power is DC (direct current) instead of AC (alternating current) a transformer called an inverter will convert DC solar power into more useful AC power. Different inverter voltages are available by wiring the transformer differently.

Transformers are 95-98% efficient
Transformers have primary side and secondary side
Primary side receives full power from generator at all times.
Secondary side supplies power to homes and businesses that do not draw full power at all times
As a result the overall efficiency of the grid is about generating the power so use and generation balance.
circuit breaker resources Circuit breaker resources
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Why you need ground wire
See inside breaker box
How to wire safety switch
How to wire whole house surge protector
Figure volts amps and watts
Figure correct wire and breaker
Types of surge protection
Price of water No water = No electricity
Power company boils water using hydrocarbon fuel, or nuclear rod.
When water turns to steam, a steam explosion occurs.
The explosive power of steam is used to rotate turbine which turns generator.
This applies to coal-fired, gas-fired, and nuclear power plants

Bath uses 20 gallons water (12-15 gallons hot water).
Shower uses 10 gallons (5-8 gallons hot water)
How much money is bath water worth?
Growth and electricity consumption
3-phase wiring
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How to wire 3-phase outlets and surge protection

How to wire 3-phase electric

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