BASIC ELECTRICAL ENGINEERING

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Name : B. Damodaram
Designation : Lecturer
Branch : Electrical & Electronics Engineering
Institute : Govt. Polytechnic, Mahabubnagar
Year/Semester : I Year
Subject : Basic Electrical Engineering
Subject Code : EE105
Topic : Conducting Materials
Duration : 50 minutes
Sub Topic : Constantan (Eureka)
Teaching Aids : PPT, Animation, Diagrams
Revised by : A.K.Srikanth, L/EEE, Q.Q.GPT, HYD

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• Understand the Properties of Manganin
• Understand the Applications of Manganin
2
Recap
In the previous class we have studied about

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• Understand the Properties of Constantan
• Understand the Applications of Constantan
On completion of this period , you would be able to
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Objectives

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What type of materials used for the following
applications ?
• High resistivity conducting material
• Constantan
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Rheostats Resistance Box
Resistance wires

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Constantan (Eureka)
• Alloy of 60% Copper , 40% Nickel
• Stable alloy with high working temperature
• Can be easily drawn into thin wires
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2. High electrical resistance
Properties of Constantan
3. Resistance is constant over wide range of
temperatures
1. Silver like in appearance
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5. Melting point is 13000 C
4. Does not rust due to air, moisture and heat

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6. Specific gravity is 1.9
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7. Temperature coefficient of resistance
is 0.000002 / 0 C
8. Resistivity is 49 µΩ-cm
9. Permissible working temperature is about
500 0C
Properties of Constantan
Contd..

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Applications of Constantan
• Used for making Rheostats, resistance wires
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• Used for Resistance boxes and motor starters
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Starter
Applications of Constantan
Contd..

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• Constantan is a stable alloy with high working
temperature.
• Constantan is an Alloy of 60% Copper,40%Nickel
• Constantan is used for Rheostats, resistance
boxes and motor starters
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Summary
In this period we have discussed about

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1. Melting point of Constantan is
a) 13000 C
b) 11000 C
c) 10200 C
d) None of the above
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Quiz

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a) Copper
b) Nickel
c) Copper and Nickel
d) None of the above
2. Constantan is an alloy of
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Quiz

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1. State the properties of Constantan
2. State the applications of Constantan.
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Frequently Asked Questions

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In the next class we will discuss about
Next Class topic
• Understand the Properties of Nichrome.
• Understand the Applications of Nichrome.

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The will to win, the desire to
succeed, the urge to reach your
full potential... these are the
keys that will unlock the door to
personal excellence.
Eddie Robinson