Cells, Batteries, Lamps, Resistors, Switches, Wires, Cables, Fuses Circuit Components Cells, Batteries, Lamps, Resistors, Switches, Wires, Cables, Fuses

Cells and Batteries Def. Cell Def. Battery Electrochemical device consisting of two eletrodes made of different materials and an electrolyte. The chemical reaction between the electrodes and the electrolyte produces voltage. Def. Battery Two or more cells electrically connected together

Cells and Batteries Classification Primary Secondary Dry Wet Not Rechargeable Secondary Rechargeable Dry Electrolyte is a paste or gel Sealed Wet Filled with acid Must have vents

Cells and Batteries Ratings Capacity refers to the amount of energy the cell can provide under specified conditions Conditions Temperature Current drain Discharge Schedule Final Output Voltage

Miniature Lamps Incandescent Tungsten Filament Wedge Base Screw Type Base Bayonet Base Flasher Lamp Uses bimetallic strip

Miniature Lamps Neon Glow Glass bulb filled with neon gas Requires 70-95 volts to light (ionization) Once lit, voltage can drop 10-15% Resistors must be used to limit current Requires no more than 2mA of current

Miniature Lamps Light Emitting Diodes Used as indicator lamps Requires limiting resistors Operate at approx. 20mA Leads must be correct polarity

Resistors Used to control current or divide voltage Classification and symbols Fixed Variable Adjustable Tapped Power ratings Tolerance Factors Color Codes

Switches Types Toggle Slide Rocker Push Button Lever

Switches Symbols and Names SPST Single Pole, Single Throw SPDT Single Pole, Double Throw DPST Double Pole, Single Throw DPDT Double Pole, Double Throw

Wires and Cables Wires Electric Cables Coaxial Cable Flat Cable Solid or Stranded Electric Cables Shielded to isolate from electromagnetic fields Used in extension and telephone cords Coaxial Cable Shielded used to connect transmitter and receivers Flat Cable Used to digital circuits

Wires and Cables Specifications Gage Number Smaller the number the larger the diameter of the wire When measuring the gage always measure the bare wire.

Fuses Short Circuit Fast burn – sensitive electrical devices Undesired conductor path exists in the circuit Examples Fuses protect against shorts Fast burn – sensitive electrical devices Medium burn – when a spike is not expected Slow burn – Electric motor, short duration Circuit breakers