How are instruments classified? Describe the different types.

How are instruments classified? Describe the different types.
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1 Answer

Answer :

The instruments are classified depending upon:

a. Principle of operation: E.g.: Magnetic meter, induction meter.

b. Permissible percentage error

c. Depending upon application: E.g.: ammeter, voltmeter, energy meter etc.

Different types:

The electronic instrument may be classified into two types:

1. Absolute instrument: The instruments which give the output in the terms of physical constants of the instruments are called as absolute instruments.

Example: Tangent galvanometer works on balance condition of current. Basically these instruments are time consuming; it takes a lot of time to complete the magnitude of the quantity under measurement. Absolute instruments are seldom used except in standard institution.

2. Secondary instrument: These are simple in construction and easy to understand.
Here the quantity can only be measured by observing the output indicated by instrument.
Example: Voltmeter, Thermometer, pressure guage.
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