Alternating Current Direct Current

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Alternating CurrentDirect Current
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Components of Electrical System

• Voltage source generator/batteries
• Conductor wires
• Control Element switch
• Load light bulb, motors, appliances

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Alternating Current

• Electrons flow back and forth 60 times per second
  
• Electrons travel in bidirectional path in circuit
• EXAMPLES
• Power generated from power plant
• Travels over long distance to your home or
  business
• VOLTAGE amounts 120v 208v 240v 480v
• Advantages?
• Disadvantages?

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Direct Current

• Maintains a constant value
• Electrons travel in a Unidirectional path, point
  to point
• EXAMPLES
• Batteries are the most common source of DC
• Primary Cells are intended for 1 use
• Secondary Cells can be recharges for multiple use

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Battery Construction

• In its simplest form a battery consists of two
  different metal (copperzinc) plates called
  electrodes which are dipped into an acid
  solution called electrolytes
• The cell then produces current through the path
  of the two metals

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Battery types

• Primary cells
• Nonrechargeable
• Alkaline
• Carbon-Zinc
• Lithium
• Mercury
• Silver-Oxide

• Secondary cells
• Rechargeable
• Lead-Acid
• Nickel-Iron
• Nickel-Cadmium
• Lead-Calcium
• Silver-Zinc

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ELECTRICAL SYMBOLS

• Load
• Battery
• AC power

• Wire
• Switch
• Lamp