State the application of phase sequence indicator; clip on ammeter, frequency meter & P.F. meter.

1 Answer

Answer :

Phase Sequence Indicator: 

1. For finding correct phase sequence of supply 

2. For obtaining exact instant of parallel operation of alternators. 

3. For obtaining reversal of rotation of A.C. motors 

Clip on Ammeter: 

4. Measurement of leakage current at grounded conductors 

5. Measurement of leakage current at single-phase or 3-phase systems 

6. Measurement of line current in live situations 

7. Measurement of charging current 

Frequency Meter: 

1. Measurement of supply frequency 

2. For obtaining exact instant of parallel operation of alternators 

3. For obtaining exact instant of parallel operation of transformers 

4. AC motor tuning 

5. Audio frequency pitch tuning 

6. RF signal calibration 

7. Parasitic harmonics and cross-modulation detection within RF signals 

8. Heavy equipment vibration monitoring 

P.F. Meter: 

 1. For obtaining power factor of the load 

 2. On the distribution panels 

 3. For electrical load monitoring 

 4. In electroplating industries 

 5. In various processes industries for measuring power factor

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