Basic House Wiring

1. Basic House Wiring

2. Electrical Measurement Terms • Amp - measures the rate of flow of electrical current • Volt - measure of pressure or force pushing electricity • Ohm - measure of electrical resistance • Watt - basic measure of electricity (amps x volts = watts)

3. Other Basic Terms • Ground - connector that runs between a device or circuit to safely conduct current to earth • Conductor - device intended to carry electrical current • Insulator - material that is a poor conductor of electricity; used to prevent electrical flow • Short circuit - accidental connection between two conductors • Overload - to run equipment in excess of its normal full load

4. Where does electricity come from? • 1) Generation • Nuclear fission - split atoms • Hydro power - moving water • Burning fossil fuels - power plants • 2) Step-up transformer • Voltage stepped up in transformer to between 69 and 345 thousand volts (sometimes even higher) • 3) Transmission lines • Electricity travels through wires over long distances

5. Where does electricity come from? (continued) • 4) Step-down transformer • Voltage stepped down in transformer at substation to between 2000 and 13000 volts • 5) Distribution Lines • Electricity travels around community (sometimes above ground and sometimes below ground • 6) Distribution transformer • Steps down voltage to between 120 and 240 volts for use in business or home • 7) Customer line • Electricity enters homes or business

6. Circuit • Path for electricity • Closed - electricity is allowed to flow • Open - electricity is stopped • Many circuits within a home

7. Fuse/Circuit Breaker Boxes • Each branch circuit is protected by fuses or circuit breakers • If too much current is used, fuses or breakers will open the circuit • Fuse - if blown needs to be replaced • Circuit breaker - “trips” to open circuit; may be reset

8. Voltage • Two wires carry 120 volts each • 120 used for lights and small appliances (outlets) • Two wires combined for 240 volts • 240 volts used for large appliances (oven, dryer, hot water heaters, air conditioners)

9. Basic Electrical Tool Kit • Screwdriver • Long-nose pliers (similar to needle nose but has curved ends) • Lineman’s Pliers • Side Cutters - Diagonal-cutting pliers • Tin Snips • Wire Stripper/Cutter (Multipurpose tool) • Cable Ripper • Fuse Puller • Fish Tape • Conduit Bender

10. Testers • Receptacle analyzer • Voltage tester • Continuity tester • Multimeter (has specific settings to test all - voltage, amperage, and resistance)

11. E (or V) I R Basic Electrical Relationship • Ohm’s Law • I = amperage (the flow of electrons) • R = resistance (resistance to the flow) • E (or V) = voltage (force behind electrons) • E = I x R

12. Basic Skills for Replacing an Extension Cord End • Use a wire ripper to slice cable sheathing • Remove cable sheathing • Use a wire stripper to remove insulation around each wire • Make necessary connections • Hook wire clockwise over screws • Twist wire clockwise for wire nuts

13. Wire Identification • Black wire - “hot”...electricity is brought to devices through this wire • White wire - “neutral”...electricity goes back through this wire • Bare Copper or Green wire - “ground”...safety for all stray electricity

14. Long Nose Pliers Back

15. Lineman’s Pliers Back

16. Side Cutters Back

17. Tin Snips Back

18. Wire Stripper/Cutter Back

19. Cable Ripper Back

20. Fuse Puller Back

21. Fish Tape Back

22. Conduit Bender Back

23. Receptacle Analyzer Back

24. Voltage Tester Back

25. Continuity Tester Back

26. Multimeter Back