1. Objective 17.01 Describe materials used in electric wiring

2. Materials used in electric wiring Wire –Size is measured by gauge The small the gauge number, the larger the wire –Kinds of wire Solid Stranded Copper : best conductors of electricity Aluminum: has to be one size larger

3. Definitions Conductor: a material that allows electricity to move readily and offers low resistance Insulator: a material that will not conduct electricity Hot wire: red or black Neutral wire: usually white Ground wire: bare or green

4. Indoor Wire T is thermoplastic used for dry locations indoors TW is moisture resistant thermoplastic for indoor dry or wet areas RHW is rubber and is heat and moisture resistance and is used for large appliances or service entrance in both wet and dry locations Others include: THHN, THW/THWN, RH, and XHHW

5. Outdoor Wire UF is underground feeder wire used for underground service and can be buried directly in soil, but not in concrete USE is underground service entrance that has to have mechanical protection (conduit) where wires enter and leave the ground

6. Outdoor Wire SE/SEU is unarmored service entrance cables used to bring service into the building ASE is armored service entrance used to bring service into a building

7. Romex Non-metallic sheathed cable Has copper wire covered with paper and vinyl for insulation Most common type used in residential construction

8. Conduit Provides mechanical protection for wires and may be flexible or non-flexible and metal or plastic depending on NEC Code requirements

9. Electrical boxes Outlet, junctions and switch boxes are electrical boxes used anywhere wires are spliced or connected to a switch, light, receptacle, etc.

10. Receptacles Duplex receptacle has places or holes to receive two plugs A 15a-240v receptacle has holes to receive one plug Dryer and range receptacles are 240v with holes to receive specific shaped plugs Porcelain receptacles for lights may have only a place for a bulb, or they may include a chain for a switch or they may also include an outlet for a plug

11. Switches Used to stop and start the flow of electricity Single pole has two terminals and controls lights form one location Three-way has three terminals and controls lights from two locations Four-way has four terminals and is used in combination with three-way switches to control lights form three or more locations

12. Misc. Blank covers are used to cover junctions boxes Wall plates are used to cover switch and receptacles boxes. Others include ground clamps, screws and clips. Entrance elbow and caps or weather heads, and insulators

13. Misc. Circuit breaker is a switching device that automatically opens the circuit when too much current passes through it Fuse has a strip of metal in it that melts when too much current passes through it. Meter is used to measure the amount of electricity used.

14. Connectors Cable connectors and split bolt connectors are used to fit knockouts in boxes and to connect outside wires to entrance wires Solderless wire connectors are used to turn wires to make a pigtail splice and to insulate the connection or splice in one operations