1. Residential Wiring Unit 3 – Installation and Planning

2. INSULATION COLORS HOT WIRE– Dark colors (Black, Red, Blue) Brings electricity from the panel to the circuit. Is always hot. NEUTRAL WIRE – (White, Beige, Gray) Returns power to ground from the loads on the circuit. Never gets wired to a switch (do not want to turn this off) GROUNDING CONDUCTORS – (Bare or Green) - Bonds the boxes and devices to ground.

3. CIRCUIT PROTECTION Fuses and Breakers – Devices that stop the flow of electricity within short circuits or overflows. – Overloads – Too many devices on one circuit. – Short circuits – When two conductors unintentionally touch each other or create a path. – Ground Faults - when electricity travels outside an intended path and tries to get to the ground by the shortest route.

4. Switches S1 = Single Pole Switch Single pole switches turn a light, receptacle or load on and off from a single location, it has an on and off marking on the switch. S3 - Three Way Switch The three way switch is always used in pairs and allows you to turn a light or receptacle on and off from two different locations. These switches have no "on" or "off" markings and three screw terminals one labelled “common”. S4 - Four Way Switch The four way switch is used in between two three-way switches to control an outlet or light fixture from three(or more) different locations. The four-way switch has four terminals most always brass in color. There is no COM or "common" wire like a three-way switch. The four-way switch simply functions as a switching device for the traveler wires between the three-way switches.

5. Wiring Outlets (receptacles) Break- away supplies power to the 2nd screw so only one black and one white wire is needed to supply power to both parts of the outlet. Switch operated outlet– gets one switch-leg (yellow) wire and one neutral (white) wire. Hot outlet – gets one hot (black) wire and one neutral (white) wire. Split-circuit receptacle = both switch operated and hot

6. Service Entrance Where the electricity enters the residence. Types of Service 1. Service Drop – overhead wires come down from the utility pole. Must be 12’ (12 feet) above residential driveways 2. Service Lateral – Wires are run underground from the utility pole to the residence. 120/240 Volt Service = 2 Hot + 1 Neutral Metering equipment – measures the use of electricity for the electric company, by how many Kwh is used.

7. Wire/Conductors You should strip ¾ - 7/8 ” for proper connections All splices are to be made within a box You are to have 6” excess wire at every opening The larger the AWG the smaller the wire

8. Grounding Grounding – the connection of all parts of wiring installation to the earth providing safety and protection of the system and the people installing and using the system. 1.) System Grounding – connection of one of the conductors (neutral) to the earth. This is done by attaching the neutral wire to all light sockets and all receptacles in the circuit. Bonding – connecting all metal parts of the system for good continuity. 2.) Equipment grounding – this is joining all metal parts of the wiring system and bonding it to the equipment grounding conductor. One conductor (green/bare) is grounded by connecting it to the grounding bus bar. The equipment ground protects the electrical equipment from damage during a ground fault ( a live conductor touches the box).

9. Installation Contractors will bid on jobs and do the work if they win the bid A supervisor will check the work before the inspector. Work will be checked by the local inspectors (ie. authorities having jurisdiction).

10. Breakers Main is usually 100 amp service – 100 x 120 volts = 1200 watts total – 100 x 240 volts = 2400 watts total 15 amp breaker at 120v = (15 x 120) = 1800 watts 20 amp breaker at 120v = (20 x 120) = 2400 watts 30 amps at 120 v = 3600 watts Note: No more than 80% of available wattage should be used.

12. Try these 1.Will a 15 amp fuse blow with a 100 watt light bulb, a 2 watt clock, a 300 watt freezer, and an 8 watt electric razor on at the same time? 2. Will a 20 amp fuse blow with a 350 watt color TV, a 175 watt clothes washer and a 4000 watt dryer on it?

13. Electrical Prints and Specs Print – is a copy of a drawing that illustrates materials, locations, and methods used for installations. Electrical Print – uses symbols to represent fixtures, receptacles, switches and panels. It is used to order the equipment, determine the length of wires and cables needed, and inform the local inspector.

14. Print Scale A Scale is used to draw a floor plan on a smaller scale. For instance a home that is 30’x 40’ may be represented using a scale of ¼” = 1’ so the home drawn will measure 7 ½” x 10” (7 ½ x 48 = 360, 360/12 = 30’) (10 x 48 = 480, 480/12 = 40’) (ie. multiply the denominator (4) by 12 to get the size of the new drawing 1/48 th the size) ½” = 1” - 1/24 th 1/8” = 1’ – 1/72 nd

15. Practice scale ¼” =1’ – A wall 6” long on a drawing would actually be what? 24’ in real life – 12 x 4 = 48, 48 x 6 = 288, 288/12 = 24’ (6 x 4 = 24) – A wall 1/12” long on a drawing would actually be what? 6’ in real life – 12 x 4 = 48, 1.5 x 48 = 72, 72/12 = 6’ (1.5 x 4 = 6)