Industrial Electronics

1
Industrial Electronics

• Lecture 2

2
Fuses

• Current limiting device
• For circuit protection
• Circuit breakers are resettable fuses

3
WIRE GAGE

• Larger number smaller the wire
• 20 gage smallest practical
• 8 is larger than 12
• 00 is larger than 0
• 000 is larger than 00

4
Types of meters

• Ammeter
• Voltmeter
• Ohmeter
• Multimeter
• Oscilloscope

5
Recognize measuring instruments
6
Making Basic Circuit Measurements
7
Making Basic Circuit Measurements
8
Ground

• Can be anywhere in a circuit
• Establish reference plane
• REMEMBER
• Voltage is relative

9
Schematic of Power Supply

• Project Page 1

10
Alternating Current

• Varies with Time
• Magnitude
• Polarity
• Direction of Electron Flow
• Usually Sinusoidal
• Could be Triangular
• Square
• Mixed Mode

11
Sinusoidal Waveforms

• Period
• The Amount of Time to Complete One Cycle
• Frequency
• How Many Cycles in a Particular Time
• Usually, cycles per second (hertz)
• Frequency is 1 / period

12
Sinusoidal Waveforms
13
Sinusoidal Waveforms

• Peak Value (Maximum and Minimum)
• Positive and Negative
• One-Half of Total Voltage or Current Variation
• Peak to Peak
• Total Change in Voltage or Current

14
Waveforms

• rms Value
• dc voltage that would produce the same effect
• average power value with time
• Sine Wave
• rms 0.707 x Peak
• Square Wave - rms Peak
• Triangular - rms 0.5 x Peak

15
Waveforms

• 110 VAC - rms or Peak ?
• 12 VDC - rms or Peak ?
• Average Voltage - Not Used

16
Oscilloscope

• Frequency - Sec/Div
• Increase Display to Maximum Size (full cycle)
• Count Squares Horizontally for One Cycle
• Multiply by Sec/Div Setting Period
• Frequency 1 / Period

17
Oscilloscope

• Magnitude
• Increase Display to Maximum Size (full cycle)
• Count Squares Vertically (Min to Max)
• Multiply by Volts/Div Setting
• This Gives Voltage Peak to Peak

18
Principles of Electromagnetism

• Oersteds Discovery
• Current Flowing Through A Wire Produces a
  Magnetic Field
• Direction of the Magnetic Field is Associated
  with the Direction of Current Flow
• Left Hand Rule

19
Oersteds Law
20
Principles of Electromagnetism

• Electromagnet
• Wrap wires carrying current around
• More wires, Stronger Field (Flux)
• More Current, Stronger Flux
• Fm N x I

21
Electromagnetic Devices

• Transformer
• Wires Wrapped Around A Bar
• Primary (Fmp) Np x Ip
• Fmp Fms (Ideal)
• Is Fms / Ns
• Direction (polarity) Related to
• Wire Wrapping Direction
• Current Direction

22
Transformers

• Used to
• Isolate electrically one circuit (supply) from
  another
• Used to alter voltage/current magnitude using
  number of turns of wire
• Primary vs Secondary about the same core

23
Transformer in Power Supply

• See Text Figure 10-9 for illustration of how a
  transformer is used in a power supply circuit

24
Full Wave Rectification

• See Section 10-5 for written explanation

25
Resistance
26
Capacitors

• Device for storing electrons(Fig 9-2)
• Composed of separated plates
• Factors affecting
• Area of plate - larger area larger C (Fig 9-6)
• Separation - Field intensity(Fig 9-7)
• closer plates higher intensity
• Dielectric strength
• determines magnitude of intensity at discharge

27
Capacitor Materials Section 3.6.5

• Mica - stacked foil or silver mica
• Ceramic - High dielectric constant
• Paper/Plastic - rolled foil
• Electrolytic - foil separated by electrolyte
• Variable - air dielectric
• Trimmers - adjust plate separation

28
Applications of Capacitance

• Rectifier (Fig 9-51)
• Tuning
• Computer Memories
• Motor Starters
• Batteries
• Compensation for Inductive Load

29
Capacitor Used for filtering

• See Figures in Section 3.6.9

30
Switches

• See Section 3.3.3

31
Voltage Regulation

• Uses Zener Diode Section 4.2.7
• See 10.1.1 and associated summary

32
Common Electrical Symbols

• Appendix B
• Be able to identify symbols in schematics
• Use correct symbols in drawing schmatics

33
Component info

• See Appendix G
• Typical resistor sizes
• Typical capacitor sizes
• IC number designations