1. { Electricity

2. { Who invented electricity? No one Benjamin Franklin is credited with the discovery.

3. { What is electricity? The movement of Electrons through a conductor.

4.  Do we value electricity?  What would our lives be like without it?  What are some things in our classroom that operate by electricity?  What are some things at your house that operate by electricity?

5. Nucleus of an atom Electrons on outer shells Electrons move from one atom to another – creating electricity How does electricity really work?

6. { Speed of Electricity Electricity travels at the speed of light which is 186,000 miles / second

7.  It is a public commodity that we buy just like we buy groceries. You can shop for groceries at Food Lion, Walmart or Piggly Wiggly. Where can you shop for electricity?  Four County Electric  South River Electric  Tri-County Electric  Duke Energy Progress (Progress Energy) Where does our electricity come from?

8.  In the early 1900’s, people wanted electricity in their homes. Companies that made electricity began to spring up all around the country.  It was very expensive to get electricity to people so, only areas of large populations were profitable.  People in rural areas lobbied congress and a new program was established to help rural communities to get electricity.  Thus the start of electric Co-ops. (Four County, South River, etc.) The Story of Electricity

9.  Electricity is made by large generators that use large magnets to create energy  Some source of power must turn a generator  Sources of Power  Hydro Electric  Fossil Fuels (natural gas, coal and oil)  Nuclear  Geo-Thermal  Wind Generation of Electricity

10.  Amperes (A) -measure of the rate of flow of electricity in a conductor  Volts (V) - measure of electrical pressure  Watts (W) - measure of the amount of energy or work that can be done  W=V x A  Kilowatt = 1000 watts  Ohms (R) - measure of electrical resistance to flow Electrical Terms

11.  Hertz (cycles) – the number of times electricity reverses flow each second. In the U.S. we use 60 Hz electricity.  Conductor – a substance that allows electric current to move through it.  Insulator - a substance that resist the movement of electricity.  Horsepower – a unit of measurement of work -  1 horsepower = 33,000 ft-lb /min. Electrical Terms Continued:

12.  Circuit Breaker – protects circuits from overload.  Circuit Breaker – protects circuits from overload of current by tripping to or open the current.  Fuse – protects circuits from overload by melting a metal strip in the fuse.  Hot Wire – a current-carrying conductor under electrical pressure.  Neutral Wire – a current-carrying conductor NOT under electrical pressure (has volts).  Ground Wire – a conducting wire that transmits current to the earth to minimize the danger of electrical shock.  Underwriter’s Laboratory – an independent organization that tests electric devices for safety.

13.  Find the 5 pieces of equipment listed & 5 of your own choosing and locate the following information:  Amps (A)  Volts (V)  Watts (W)  Horsepower (Hz)  Hertz (Hz)  Ohms ( R)  Underwriter’s Laboratory (UL) Electricity Scavenger Hunt

14.  Watts =- V x A  Volts = W / A  Amps = W / V  1 horsepower = 742 watts (rounded to 1000)  1 kilowatt = 1000 watts Formulas

15.  Ohm = R  Volts = E  Amps = I  Ohm’s Law: E = IR I=E/RR=E/I Ohm’s Law

16.  Power from from power company  Transformer: drops volts from 25,000 volts to 240 volts  Service drop: wires etc from transformer to house  Entrance head: weather-proof at house  Meter: $$$  Service Entrance Panel (SEP): box with fuses or breakers Service Entrance

17.  Kilowatthours: how electricity is sold  Kilo = 1000  Watthour = use of 1 watt for one hour  100 watt light bulb for 1 hour - 100 watthours  Kilowatthour = 1000 watts for one hour  Pointer Meter is used to measure electrical ususage. Electric Meter

18.  Nonmetallic sheathed cable: copper or alluminum wire covered with paper, rubber, or vinyl for insulation  Armored cable: flexible metal sheath with individual wires inside. Wires are insulated  Conduit: tubing with individually insulated wires Types of Cable

19.  copper  No 14 (14 gauge) = 15 amp circuits  No 12 = 20 amps  No 10 = 30 amps  aluminum use one size larger  lower gauge number = larger wire  No 8 and larger use bundles of wires  current travels on outer surface of wire, so a bundle of smaller wires can carry more Wire Type and Size

20.  loss of voltage as it travels along a wire  lights dim, motors overheat  larger wires have less voltage drop for a given amount of current  longer wire = greater problem  must increase wire size as distance increases Voltage Drop

21.  Type T - dry locations  Type TW - dry or wet  THHN - dry, high temps  THW and THWN - wet, high temps  XHHW - high moisture & heat resistance  UF - direct burial in soil but not concrete Wire Types

22.  Color coded: black, red, & blue = positive or hot wires which carry current to appliances  White = neutral wires carry current from appliance back to source  Green or Bare = ground all metal boxes and appliances Wire Identification

23.  Wire Size: 12-2 has two strands of No. 12 wire (black & white)  12-2 w/g same, with one green or bare  12-3 has three strands of No. 12 (black, red, white)  12-3 w/g same, with green or bare Wire Identification

24. Reading the Pointer Meter 2 5987

26. Electrical Equipment and Supplies  Single Pole Switch  3-way Switch  4-way Switch  Duplex Receptacle  Keyless Socket  Circuit Breaker  Thermostat  GFCI  Switch Box  Junction Box  Wire Nuts  Wire Strippers  Long Nose Pliers  Side Cutting Pliers  Screwdriver  Multimeter