Transducer

1. April 23 By Gordon Shering
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Transducers
Gordon Shering

2. April 23 By Gordon Shering
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Introduction
 What is a transducer.
 Different types of transducers.
 Examples of commercial transducers.
 Using transducers on control systems.

3. April 23 By Gordon Shering
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What is a Transducer?
 A device for turning one form of energy into
another form of energy.
Input Output
Transducer

4. April 23 By Gordon Shering
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What is a Transducer?
 The input can be length, force, pressure, light,
tempature etc.
 The output can be anything but most typically an
electrical (analogue) signal.
 The analoge siganal may be converted into a digital
signal with an ADC for computer systems
Input Output
Transducer

5. April 23 By Gordon Shering
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Transducers
 The input can be length, force, pressure, light,
tempature etc.
 The output can be anything but most typically an
electrical (analogue) signal.
 The analoge siganal may be converted into a digital
signal with an ADC for computer systems
Input Output
Transducer

6. April 23 By Gordon Shering
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Position Transducers
 A Potentiometer may be used to
measure position or movement.
 Electrical contacts age and can become
unreliable.

7. April 23 By Gordon Shering
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Liquid Level Transducers
 A Potentiometer used with a float to
measure liquid level.
 Is this used in a car to measure petrol?.

8. April 23 By Gordon Shering
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Pressure Transducers
 A Potentiometer used with bellows
or a diaphragm to measure presure.

9. April 23 By Gordon Shering
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Pressure Transducers
 Other ways to measure pressure.

10. April 23 By Gordon Shering
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Position Transducers (Magnetic)
 Using magnetic coupling has the advantage
that there are no rubbing contacts.

11. April 23 By Gordon Shering
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Position Transducers (Capacitive)
 Using capacitive coupling can also be used
and also has the advantage that there are no
rubbing contacts.

12. April 23 By Gordon Shering
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Position Transducers (Optical)
 Optics can be used to give a digital output
directly. In this case rotational position is being
measured.

13. April 23 By Gordon Shering
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Position Transducers (Optical)
 What is the name for the cyclic code on the right.?
 Why is the wheel on the write normally used instead
of the wheel on the left.?

14. April 23 By Gordon Shering
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Force Transducers (Strain gauge)
 A strain gauge can be used to measure force.
 This could be used as a weighing machine.

15. April 23 By Gordon Shering
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Force Transducers (Strain gauge)
 Real commercial strain gages are
designed to give maximum
sensitivity.

16. April 23 By Gordon Shering
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Temperature Transducers
 A thermo couple uses two different
metals that generate a voltage when
they are heated.