agricultural electricity. what is electricity? easier to describe what it does than what it is! the...

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Agricultural Electricity

What is Electricity?

• Easier to describe what it does than what it is!

• The flow/movement of electrons through a material.

Direct Current (DC)

• Flow of electrons in only one direction.

• Produced by:• DC Generators• Batteries• Solar (PV) Cells• Wind Turbines

Alternating Current (AC)

• Flow of electrons in one direction and then the other.

• Produced by AC generators.

• Supplied by Modern Power Suppliers.

How do they flow?

• Conductors• Materials that allow electrons to readily

move from one atom to another.• Most metals are good conductors. (silver,

copper, gold, aluminum) • What about water?• Distilled water?

Copper vs. Aluminum

Copper Aluminum-Used Primarily on -Used primarily on the customer side the utility side of of the meter. the meter.-A better conductor -Not as good a

than aluminum. conductor as copper.-More expensive. -Less expensive.

-Lighter.

Insulators

• Materials that do not allow their electrons to readily move from atom to atom.

• Rubber, plastic, glass, porcelain, ceramics.

Voltage (Volts)

• The pressure/force pushing the electrons through the material.

• Similar to water pressure in a water piping system.

• Supplied by the generator.

• Symbol= E or V

Kilovolt (kV)

• 1000 volts

• Used to define the voltages of transmission lines and higher voltage distribution lines.

• Examples:• 345 kV line=345,000 volts• 12.5 kV line=12,500 volts

Current (Amps)• The rate of flow of the electrons through the

material.• Similar to the flow rate (gallons/minute) in a

water pipe.• One Ampere=6,280,000,000,000,000,000

electrons per second• Byproducts

• Heat• Magnetic Fields

•Symbol=I or A

Resistance (Ohms)

• Measure of a materials impedance/resistance to the flow of electricity through it.

• Similar to the friction/head loss in a water piping system.

• Symbol= omega

Resistance Creates Voltage Drop

• Voltage drops on a circuit the farther you get from the source.

• Low voltage can cause:• Dim lights• Hot motors• Reduced motor life

Real Power (Wattage..Watts)

• A measure of the power used by an appliance.

• “The rate or ability to do work”

• Symbol: W

Kilowatts

• 1000 Watts

• Most power suppliers use kilowatts to quantify how much power commercial/industrial customers use for billing purposes.

• Symbol=kW

Megawatts

• 1,000,000 watts

• Commonly used by electrial people to measure the power a generator is capable of producing or the power requirements of large customers or cities.

• Symbol=MW

Ohm’s Law

• The basic physical law describing how electricity acts.

• Volts=Amps X Ohms

• Helps us figure out “How big should the wires be?”

Why can’t I run my coffee pot, toaster, blender & microwave without the

breaker tripping?• How many amps does a circuit with a

1000 watt coffee maker, a 500 watt toaster, a 200 watt blender and a 700 watt microwave draw when all operate?

Use Watt’s Law

• 700+1000+500+200=2400 Watts

• Watts=Volts X Amps

• 2400 Watts divided by 120 volts=20 amps

Practice

• On a 120 volt system how many amps will a 800 watt microwave, 1000 watt coffee maker, a 500 watt toaster and a 200 watt radio.

• Watts= volts x amps

Long-Nose Pliers

Multipurpose Tool

Wire Strippers

Cable Ripper

Lineman’s pliers

Automatic wire strippers

MultiMeter

Amp Meter

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