Page 202 - CITS - Electrician - Trade Practical

ELECTRICIAN - CITS

TASK 2: Vary the excitation and control the power factor at no load and full load

1 Vary the field current from zero to rated value and note down corresponding power factor and armature current
covering a range from low lagging to low leading power factor through a unity power factor.
2 Tabulate Field current and armature current

3 verify the armature current is minimum when the p.f. in unity.
4 Repeat step No.1 to 3 for full load on the synchronous motor, by mechanical load.
Readings on no load

Sl.No Armature Current (I ) Field Current (I )
a f

Readings at full load

Sl.No Armature Current (I ) Field Current (I )
a f

TASK 3: Plot the V-curve
1 Plot V curve as Armature current Vs filed current for half load and full load.
Follow the manufacturer recommended range of power factor in operation as current at lagging
and leading power factors will be more to take the load.

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CITS : Power - Electrician & Wireman - Exercise 83