Page 228 - CITS - Electrician - Trade Practical

ELECTRICIAN - CITS

EXERCISE 90 : Test burnt stator and demonstrate rewinding

procedure

Objectives

At the end of this exercise you shall be able to:
• test ac motor winding by growler
• collect data for rewinding and record
• demonstrate rewinding of ac motor.
Requirements

Tools/Instruments Equipment/Machines
• SEC cu wire - 400 g • Winding former
• Electric soldering iron 25W/240V - 1 No. Materials
• Hack saw blade - 1 No. • Soldering paste - 10 g
• Standard wire gauge • Resin core solder - 50 g
Procedure

TASK 1 :
1 Switch on the power to the internal growler.
2 Move the internal growler over the coils of the stator.
3 Identify the shorted coil by buzzing/growling sound.

4 Test for open by series test lamp in any phase winding.
5 Identify the open in phase winding by testing continuity of the coil
6 Record name plate details.
7 Remove pulley by pulley puller, remove fan cover and fan blade.
8 Mark and remove connection leads from terminal box.
9 Loosen screw from end shields and remove centrifugal switch
10 Remove rotor from stator
11 Inspect for any defect/
12 Mark stator for connection lead side with respect to terminal box
13 Trace the internal connection from and draw the connection diagram

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CITS : Power - Electrician & Wireman - Exercise 89