Agricultural Electricity What is Electricity Easier to describe
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 -Used Primarily on the customer side of the meter. -A better conductor than aluminum. -More expensive. Aluminum -Used primarily on the utility side of the meter. -Not as good a conductor as copper. -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 (k. V) • 1000 volts • Used to define the voltages of transmission lines and higher voltage distribution lines. • Examples: • 345 k. V line=345, 000 volts • 12. 5 k. V 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 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=k. W
Megawatts • 1, 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
Diagonal-Cutting Pliers
Crimper
Multipurpose Tool
Wire Strippers
Cable Ripper
Lineman’s pliers
Automatic wire strippers
Multi. Meter
Amp Meter
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