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## ELECTRICITY

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**ELECTRICITY**for kitchens & baths**Electricity**Amber**Electricity**• We know that electricity behaves in a consistent predictable manner, in given situations, but electricity has never clearly been defined. • Atoms –neutrons, protons and electrons • Atoms are neutrally charged • Most of the weight of an atom is found in the protons and neutrons. • Protons are more or less attached to the nucleus • Electrons revolve around the nucleus like planets revolve around the sun**Electricity**Atom**Electricity**• Some electrons, particularly in metals are loosely bound and can detach and become “free electrons” • Free electrons as the name implies can move freely from atom to atom • When a force or pressure is applied free electrons begin to move**Electricity**• The materials that allow this movement are called CONDUCTORS • The three metals that make the best conductors: • Silver • Copper • Aluminum**Electricity**Copper Atom**Electricity**Silver atom**Electricity**• Insulators or Non Conductors: • Dry Wood • Glass • Rubber • Mica • Asbestos • Semi-Conductors: • Silicon**Electricity**Charged Bodies • Like charges repel • Unlike charges attract**Electricity**• Electrical energy is transferred through conductors by means of movement of free electrons • A material’s ability to conduct current flow determines whether it is a good or bad conductor**Electricity**Terms • Voltage • Amperage (current) • Resistance (Ohms) • Wattage (power)**Electricity**Theforce that moves electrons in a conductor can be called • VOLTAGE**Electricity voltage**• Current that flows through electrical conductors is directly proportional to the difference in potential • Current is directly proportional to the amount of voltage • Voltage increases – current increases • Voltage decreases-current decreases**Electricity voltage**Six Methods of Producing Voltage • Friction – Static electricity • Pressure – Compression of crystals • Heating – In copper, electrons move away from the heat. In iron they move to the heat. • Light – Photoelectric cells • Chemical Action - Batteries • Magnetism**Electricity charge**What is Charge? The stuff inside conductors It’s the free electrons How do we measure charge? 1 Coulomb = 6.28 x 1018 electrons 6,280,000,000,000,000,000 Ampere = 1 coulomb of charge flow per second**Electricity charge**• The copper wire is full of “charged stuff” but there is no movement**Electricity charge**The battery drives the ring of charge into motion, the charge moves along like a drive belt, and the light bulb filament “rubs” against the moving charge which makes it glow white hot.**Electricity charge**• The higher the amperage the faster charge stuff moves • The more charge stuff that flows (though a larger wire) the higher the amperage • A fast flow through a narrow wire can have the same amps as a slow flow of charge through a bigger wire. • If you keep the speed constant and increase the size of the wire you also increase the amperage**Electricity watts**Watts is the name given to electrical flow – but what flows? Energy Energy is measures in joules A joule of electrical energy can move from place to place along the wires. The amount of energy that flows in one second is one watt**Electricity**btu’s • BTU short for British thermal unit, a British standard unit of energy. One Btu is equal to the amount of heat required to raise the temperature of one pound of liquid water by 1 degree Fahrenheit at its maximum density, which occurs at a temperature of 39.1 degrees Fahrenheit. One Btu is equal to approximately 251.9 calories or 1055 joules. • As a rough guide, 1 joule is the absolute minimum amount of energy required (on the surface of Earth) to lift a one kilogram object up by a height of 10 centimetres.**Electricity closed circuits**• A closed loop of wire is not necessarily a circuit unless voltage is present. • In any electric circuit where electrons move around, three things are present: • Voltage • Current • Resistance**Electricity closed circuits**• The physical pathway for current flow is actually the circuit and it’s resistance controls the amount of current flow around the circuit. • By knowing any two of the three quantities, the third can be calculated.**Electricity ohms law**• Ohms Law – The current in a circuit is directly proportional to the applied voltage and indirectly proportional to the circuits resistance. I = current measured in amperes (amps) E = Voltage R = Resistance in Ohms**Electricity ohms law**Battery = 1.5 volts Resistance = 1.5 ohms Amperes = ? Amperes = 1**Electricity ohms law**Battery = 3 volts Resistance = 1.5 ohms Amperes = ? Amperes = 2**Electricity ohms law**Battery = 1.5 volts Resistance = 3 ohms Amperes = ? Amperes = .5**Electricity ohms law**• Another way of writing ohms law:**Electricity watts**Watts is the name given to electrical flow – but what flows? Energy Energy is measures in joules A joule of electrical energy can move from place to place along the wires. The amount of energy that flows in one second is one watt**Electricity watts**• Power pertains to the rate at which work is being done. • Work is done whenever a force causes motion i.e. when voltage causes electrons to move in a circuit work is done • The rate at which this work is done is called the electric power rate and is measured in WATTS**Electricity watts power**Watts = the amount of voltage across a circuit x the current through the circuit or Watts = Volts x Amperes or P= EI**Electricity watts power**15amp circuit *120volts =1800watts 100watt bulb*10 =1000watts**Electricity What you need to remember**• Voltage – Theforce that moves electrons in a conductor. Electrical pressure • Amperage – The rate of flow of electrical current. • Watts – The measure of the amount of electrical power. • Watts = Volts X Amps**Kitchen Electricity Circuits**• Four types of circuits for the Kitchen • General Lighting • Small Appliance • Individual Appliance • Ground Fault Circuit Interrupter**Electricity Circuits**• General Lighting – rules of thumb • One 15 amp circuit per 600 square feet • Rule of thumb – 12 outlets • Or one 20 amp circuit per 800 square feet • Rule of thumb – 16 outlets Note: Lights in kitchens and baths must be permanently wired.**Kitchen Electricity Circuits**Receptacle Circuits – Rule of thumb • 12 receptacles for a 15-amp circuit • 16 receptacle for a 20-amp circuit • Small appliance circuits • Two 20-amp circuits • One or more 20-amp circuits in the dining room or family room • These circuits may not be used for lighting**Electricity**circuits • Individual Appliance Circuits are dedicated to devices that draw enough current to warrant their own circuit.**Appliance Voltage**Garbage Disposer120 Electric Range/Cooktop 240 Gas Range/Cooktop 120 Dishwasher 120 Electric Tankless Hot Water 240 Refrigerator 120 Microwave Oven 120 Exhaust Fan 120 Breaker Capacity Amps 20 50 20 20 30 20 20 20 Electricity circuits