Download series-parallel circuits - Pearson Higher Education

OBJECTIVES
After studying Chapter 7, the reader should be able to:
1. Prepare for ASE Electrical/Electronic Systems
(A6) certification test content area “A” (General
Electrical/Electronic System Diagnosis).
2. Identify a series-parallel circuit.
3. Calculate current flow and voltage drops in a
series-parallel circuit.
4. Identify where faults in a series-parallel circuit can
be detected or determined.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
SERIES-PARALLEL CIRCUITS
• Series-parallel circuits are a combination of
series and parallel segments in one complex
circuit.
• A series-parallel circuit includes both parallel
loads or resistances, plus additional loads or
resistances that are electrically connected in
series.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
SERIES-PARALLEL CIRCUITS
• A circuit where the load is in series with other loads
is parallel.
FIGURE 7-1 A series-parallel circuit.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
SERIES-PARALLEL CIRCUITS
• A circuit where a
parallel circuit contains
resistors or loads are in
series in one or more
branches.
FIGURE 7-2 This complete
headlight circuit with all bulbs and
switches is a series-parallel circuit.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
SERIES-PARALLEL CIRCUITS
Series-Parallel Circuit Faults
• If a conventional parallel circuit, such as a
taillight circuit, had an electrical fault that
increased the resistance in one branch of the
circuit, then the amount of current flow
through that one branch will be reduced.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
SOLVING SERIES-PARALLEL CIRCUIT
PROBLEMS
• The key to solving
series-parallel circuit
problems is to combine
or simplify as much as
possible.
FIGURE 7-3 Solving a series-parallel circuit
problem.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
SERIES-PARALLEL CIRCUIT
EXAMPLES
• Each of the four examples includes solving
for the following:
– Total resistance
– Current flow (amperes) through each branch, as
well as total current flow
– Voltage drop across each resistance
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
SERIES-PARALLEL CIRCUIT
EXAMPLES
FIGURE 7-4 Example 1.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
SERIES-PARALLEL CIRCUIT
EXAMPLES
FIGURE 7-5 Example 2.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
SERIES-PARALLEL CIRCUIT
EXAMPLES
FIGURE 7-6 Example 3.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
SERIES-PARALLEL CIRCUIT
EXAMPLES
FIGURE 7-7 Example 4.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
SUMMARY
1.
A series-parallel circuit is called a compound circuit or a
combination circuit.
2.
A series-parallel circuit is a combination of a series and a
parallel circuit, which does not include fuses or switches.
3.
A fault in a series portion of the circuit would affect the
operation if the series part was in the power or the ground
side of the parallel portion of the circuit.
4.
A fault in one leg of a series-parallel circuit will affect just
the component(s) in that one leg.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
REVIEW QUESTIONS
1. Explain why an increase in resistance in the series
part of a series-parallel circuit will affect the
current (amperes) through the parallel legs
(branches).
2. What would be the effect of an open circuit in one
leg of a parallel portion of a series-parallel circuit?
3. What would be the effect of an open circuit in a
series portion of a series-parallel circuit?
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
1. Half of the dash is dark. Technician A says
that a defective dash light dimmer can be
the cause because it is in series with the
bulbs that are in parallel. Technician B says
that one or more bulbs could be defective.
Which technician is correct?
a)
b)
c)
d)
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
2. All brake lights are dimmer than normal.
Technician A says that bad bulbs could be
the cause. Technician B says that high
resistance in the brake switch could be the
cause. Which technician is correct?
a)
b)
c)
d)
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
3. See Figure 7-8 to solve for total resistance (RT) and total
current (IT).
a)
b)
c)
d)
10 ohms ÷ 1.2 A
4 ohms ÷ 3 A
6 ohms ÷ 2 A
2 ohms ÷ 6 A
FIGURE 7-8 Chapter quiz
question 3.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
4. See Figure 7-9 to solve for the value of R3 and total
resistance (RT).
a)
b)
c)
d)
12 ohms ÷ 12 ohms
1 ohm ÷ 7 ohms
2 ohms ÷ 8 ohms
6 ohms ÷ 6 ohms
FIGURE 7-9 Chapter quiz
question 4.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
5.
See Figure 7-10 to solve for voltage (E ) and total resistance (RT).
a)
b)
c)
d)
16.3 volts ÷ 12 ohms
3.3 volts ÷ 2.4 ohms
1.36 volts ÷ 1 ohm
6 volts ÷ 4.4 ohms
FIGURE 7-10 Chapter
quiz question 5.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
6.
See Figure 7-11 to solve for R1 and total resistance (RT).
a) 3 ohms ÷ 15 ohms
b) 1 ohm ÷ 15 ohms
c) 2 ohms ÷ 5 ohms
d) 5 ohms ÷ 5 ohms
FIGURE 7-11 Chapter quiz
question 6.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
7.
See Figure 7-12 to solve for total resistance (RT) and total current (I ).
a) 3.1 ohms ÷ 7.7 amperes
b) 5.1 ohms ÷ 4.7 amperes
c) 20 ohms ÷ 1.2 amperes
d) 6 ohms ÷ 4 amperes
FIGURE 7-12 Chapter quiz
question 7.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
8.
See Figure 7-13 to solve for the value of E and total resistance (RT).
a)
b)
c)
d)
13.2 volts ÷ 40 ohms
11.2 volts ÷ 34 ohms
8 volts ÷ 24.2 ohms
8.6 volts ÷ 26 ohms
FIGURE 7-13 Chapter quiz
question 8.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
9.
See Figure 7-14 to solve for total resistance (RT) and total current (I ).
a)
b)
c)
d)
1.5 ohms ÷ 8 amperes
18 ohms ÷ 0.66 ampere
6 ohms ÷ 2 amperes
5.5 ohms ÷ 2.2 amperes
FIGURE 7-14 Chapter quiz
question 9.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
10. See Figure 7-15 to solve for total resistance (RT) and total current (I ).
a)
b)
c)
d)
48 ohms ÷ .42 ampere
20 ohms ÷ 1 ampere
30 ohms ÷ .66 ampere
10.2 ohms ÷ 1.96 amperes
FIGURE 7-15 Chapter quiz
question 10.
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
END
Automotive Electricity and Electronics, 2/e
By James D Halderman
© 2009 Pearson Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458