Schematic and Schematic Symbols
5 February 2004
Schematic Diagrams and Symbols
Objective
• At the conclusion of this presentation the student will
– Describe and identify Standard Schematic Symbols
– Draw a Schematic Diagram
– Show polarity of components in the circuit based on the
connection of the source
– Connect components and meters to the circuit
5 February 2004
Professor Andrew H. Andersen
Schematic and Schematic Symbols
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Schematic and Schematic Symbols
5 February 2004
The Basic Circuit
• An electric circuit consists of a voltage source, one or more
components (or load), and a path for current between the
source and the load
• A closed circuit is one in which the current has a complete
path
• An open circuit is one in which the current path is broken, or
incomplete
5 February 2004
Schematic and Schematic Symbols
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Ground
• Ground is the reference point in electric circuits and has a
potential of 0 V with respect to other points in the circuit
• All ground points in a circuit are electrically the same and are
therefore common points
Earth Ground
5 February 2004
Professor Andrew H. Andersen
Chassis Ground
Schematic and Schematic Symbols
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Schematic and Schematic Symbols
5 February 2004
Schematic Showing Ground Connection
5 February 2004
Schematic and Schematic Symbols
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Some Basic Schematic Symbols
5 February 2004
Professor Andrew H. Andersen
Schematic and Schematic Symbols
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Schematic and Schematic Symbols
5 February 2004
The Series Circuit
• Single path from + terminal of source, through components, to – terminal
of the source
– Current is the same everywhere in the circuit
• There are 3 nodes in the circuit shown
• If a component is added in series
– Break the circuit where you wish to add the component
– Enter the component and wires as necessary to complete the circuit
– Each component added in series adds one more node
5 February 2004
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The Parallel Circuit
• Multiple paths from + terminal of source, through components, to –
terminal of the source
– Current in each branch depends on value of branch resistance
• There are 2 nodes in the circuit shown
• If a component is added in parallel
– Enter the component in parallel where desired
– Add wires as necessary to complete the circuit
– When a component is added in parallel does not create a new node
5 February 2004
Professor Andrew H. Andersen
Schematic and Schematic Symbols
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Schematic and Schematic Symbols
5 February 2004
The Series-Parallel Circuit
• R1 and R3 are in series
• The series combination of R1 and R3 is in Parallel with R2
5 February 2004
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The Series-Parallel Circuit
• R2 and R3 are in Parallel
• The Parallel combination of R2 and R3 is in series with R1
5 February 2004
Professor Andrew H. Andersen
Schematic and Schematic Symbols
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Schematic and Schematic Symbols
5 February 2004
Circuit with Resistors, Meters, and a Switch
SPDT
5 February 2004
Schematic and Schematic Symbols
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Example of Resistors Connected to a Rotary Switch
5 February 2004
Professor Andrew H. Andersen
Schematic and Schematic Symbols
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Schematic and Schematic Symbols
5 February 2004
Lamps and Switches
5 February 2004
Schematic and Schematic Symbols
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Rotary and SPST Switches
5 February 2004
Professor Andrew H. Andersen
Schematic and Schematic Symbols
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Schematic and Schematic Symbols
5 February 2004
Measuring Current
5 February 2004
Schematic and Schematic Symbols
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Measuring Voltage
5 February 2004
Professor Andrew H. Andersen
Schematic and Schematic Symbols
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