Procedure for Calibration of AC Voltmeter and AC Ammeter :

Calibration of Ammeter :

1. Set Up the Circuit:

   • Connect the circuit as per the given diagram.
   • Ensure the ammeter is placed in series with the load and power source.

2. Increase the Load Step by Step:

   • Use the single-pole switches to gradually increase the load.
   • Start with the lowest load setting and increase it incrementally until the ammeter shows full-scale deflection.

3. Take Observations:

   • Record the ammeter reading (testing value) and the corresponding standard value (from a reference instrument) at each step.
   • Perform at least six observations across the range of the ammeter.

4. Calculate Percentage Error:

   • For each observation, calculate the percentage error using the formula:

     Percentage Error = (|Testing Value - Standard Value| / Standard Value) * 100
               

5. Repeat if Necessary:

   • Check consistency of readings and repeat the measurements if needed to ensure accuracy.

Calibration of Voltmeter :

1. Set Up the Circuit:

   • Connect the circuit as per the given diagram.
   • Ensure the voltmeter is connected in parallel with the load.

2. Adjust the Rheostat:

   • Adjust the rheostat to set the voltmeter to a low value initially.

3. Increase Voltage Step by Step:

   • Gradually increase the voltage by adjusting the rheostat, ensuring the voltmeter displays readings up to full-scale deflection.

4. Take Observations:

   • Record the voltmeter reading (testing value) and the standard value (from a reference device) at each step.
   • Perform at least six observations across the full voltage range of the voltmeter.

5. Calculate Percentage Error:

   • For each observation, calculate the percentage error using the formula:

     Percentage Error = (|Testing Value - Standard Value| / Standard Value) * 100
               

6. Repeat if Necessary:

   • Check the consistency of readings and repeat the measurements if needed.