Page 205 - CITS - Electrician - Trade Practical

ELECTRICIAN - CITS

EXERCISE 85 : Check and correct Power factor

Objectives
At the end of this exercise you shall be able to:
• connect 3-phase motor with the starter as load requiring pf improvement
• connect 3 phase synchronous motor as synchronous condenser
• improve the power factor of lagging motor load.

Requirements

Tools/Instruments Materials
• Electrician Tool kit - 1 Set • ICTP switch 16A 500V - 1 No
• MI Voltmeter 0-500V - 1 No • Lamp holder pendent - 2 Nos
• MI Ammeter0-15A - 1 No • Lamp 250V, 60 or 100 watts bulb - 2 Nos
• MC Ammeter 0 to 2.5A - 1 No • Stranded PVC insulated wire
• MC Ammeter 0 to 15A - 1 No 7/1.5 aluminium cable - 4 m
• MC Voltmeter 0 to 250 volt - 1 No • D.P.S.T. Switch 16A, 250V - 1 No
• Power factor meter 500V 15A 0.5 lag • PVC insulated connecting cable - as reqd
to 0.5 lead - 1 No • ICDP switch 16A 250V - 1 No
• Tachometer multi-range • Graph sheet - as reqd
0-300/1000/3000 rpm - 1 No

Equipment/Machines
• 3 phase induction motor - Synchronous motor -
5HP 415V three phase

Procedure

TASK 1: Start the synchronous motor
1 Connect three phase induction motor as per diagram Fig 1
2 Start and run three phase induction motor at no load.
3 Measure the power factor.

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