Name two methods for measurement of low, medium and high resistance. Give one advantage and one limitation of V- I method.

1 Answer

Answer :

Methods for measurement of low resistance: 

1. Ammeter voltmeter method 

2. Kelvin’s bridge method 

3. Ohm meter method 

4. Potentiometer method 

5. Digital/analog multi-meter method. 


Methods for measurement of medium resistance: 

1. Ammeter voltmeter method 

2. Digital/analog multi-meter method. 

3. Wheatstone bridge method 

4. Substitution method. 

5. Carry- foster method 


Methods for measurement of high resistance: 

1. Direct deflection method 

2. Loss of charge method 

3. Megger 


Advantages of V-I method: 

1. Simple and economical method 

2. Reasonably accurate

3. Instruments for test are easily available. 


Limitation of V- I method: 

1. Ammeter resistance must be zero and voltmeter resistance must be infinity for perfectly accurate measurement which is not possible. 

2. Connection errors.

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