State the meaning of secondary instrument. Classify secondary instruments.

State the meaning of secondary instrument. Classify secondary instruments.
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1 Answer

Answer :

Secondary instruments: - Gives reading directly of the quantity being measured. - Calibrated with respect to absolute instruments 

Classification of Secondary instruments: 

1. Depending on the principle of operation: i) Magnetic meters ii) Induction meters iii) Hot wire meters iv) Electrostatic meters 

2. Depending on construction: i) Indicating instruments ii) Recording instruments iii) Integrating instruments 

3. Depending on permissible error: i) Standard meters ii) Substandard meters iii) First grade instruments.

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