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ELECTRICITY

ELECTRICITY

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ELECTRICITY

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  1. ELECTRICITY for kitchens & baths

  2. Electricity Amber

  3. 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

  4. Electricity Atom

  5. 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

  6. Electricity • The materials that allow this movement are called CONDUCTORS • The three metals that make the best conductors: • Silver • Copper • Aluminum

  7. Electricity Copper Atom

  8. Electricity Silver atom

  9. Electricity • Insulators or Non Conductors: • Dry Wood • Glass • Rubber • Mica • Asbestos • Semi-Conductors: • Silicon

  10. Electricity Charged Bodies • Like charges repel • Unlike charges attract

  11. 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

  12. Electricity Terms • Voltage • Amperage (current) • Resistance (Ohms) • Wattage (power)

  13. Electricity

  14. Electricity Theforce that moves electrons in a conductor can be called • VOLTAGE

  15. 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

  16. 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

  17. 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

  18. Electricity charge • The copper wire is full of “charged stuff” but there is no movement

  19. Electricity charge

  20. 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.

  21. 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

  22. 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

  23. 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.

  24. 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

  25. 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.

  26. 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

  27. Electricity ohms law Battery = 1.5 volts Resistance = 1.5 ohms Amperes = ? Amperes = 1

  28. Electricity ohms law Battery = 3 volts Resistance = 1.5 ohms Amperes = ? Amperes = 2

  29. Electricity ohms law Battery = 1.5 volts Resistance = 3 ohms Amperes = ? Amperes = .5

  30. Electricity ohms law • Another way of writing ohms law:

  31. 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

  32. 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

  33. 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

  34. Electricity watts power

  35. Electricity watts power

  36. Electricity watts power

  37. Electricity watts power

  38. Electricity watts power 15amp circuit *120volts =1800watts 100watt bulb*10 =1000watts

  39. 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

  40. Kitchen Electricity Circuits • Four types of circuits for the Kitchen • General Lighting • Small Appliance • Individual Appliance • Ground Fault Circuit Interrupter

  41. 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.

  42. 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

  43. Electricity circuits • Individual Appliance Circuits are dedicated to devices that draw enough current to warrant their own circuit.

  44. 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