Page 181 - CITS - Electrician - Trade Practical

ELECTRICIAN - CITS

EXERCISE 75 : Check,dismantle and reassemble of
different types of 1f motors

Objectives

At the end of this exercise you shall be able to:
• dismantle the motor
• inspect the performance of the motor
• reassemble the motor
• test the motor in no-load condition.

Requirements

Tools/Instruments Equipments/Machines
• Combination pliers 150mm -1 No. • 1Ф Squirrel cage Induction
• Screw driver 100,150,200mm -1 No. Motor 1.5HP,1440rpm -1 No.
• D.E. spanner set 5mm – 30mm -1 No. Materials
• Ring spanner 5mm to 30mm -1 No. • Cotton waste -100gm
• Cold chisel 25mm x 200mm -1 No. • Grease lithium based -250gm
• Ball peen hammer 500gms -1 No. • Sand paper 220size -1 No.
• Nylon hammer 75mm x 100mm -1 No.
• Pulley puller 200mm 3 jaws -1 No.
• Centre punch 10mm x 150mm -1 No.
• Megger 500 V -1 No.

Procedure

TASK 1: Dismantle the given motor
1 Collect the name plate details and record it.

2 Remove the shaft key or grab screw holding the pulley Fig 1
3 Remove the pulley by using suiTable pulley puller. Fig 2

Fig 1 Fig 2

4 Make a centre punch alignment mark on the stator and the end shield cover.Fig 3

To avoid confusion, make a single punch mark on one side and dual punch mark on the other end
of the motor.
5 Remove the grease cup screw.
6 Loosen the bolts gradually, switching from side to side until they can be removed.Fig4

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