DC Motor Repair
1. Repairing of field winding DC motor
A. Preparation of Coils
The wooden former are used for preparation of field coils of D.C motor the former is selected according to the size of coil. The wooden paces situated in the former is lightly tapered which makes the coils preparation easy.
First of all a cotton tape is placed on the former which is use to tie up the winding after .its preparation so that its remains as it is when it is taken out the paper insulation is also placed on the former now the coil is prepared having same number of turns and shape which means the original point. In D.C series motor the coil has less no of turns and the diameter of conductor is selected according to the power, voltage and current rating of the motor.
In DC shunt motor the coil has more no of turns of the conductor having small diameter. The no of turns are counted. The no of turns must be equal to the original coil. In D.C compound motor there are smooth. The series and shunt winding, in small size motor, the wooden former, now layer of insulation is placed on its danger size motor, the shunt and series field winding are prepared separately and then installed in the motor.
B. Inter poles
Inter poles are used between the main pole and on geometrical neutral axis they produced dew to armature reaction that’s why the coil undergoing commutation does not experienced, flux linkage change.
2. Separation of bearing
For separating the bearing from the shaft a puller is used. It is used in same way lockage the puller of shaft coupling. the hocks are fixed on bearing and the threaded screw is rotated which pulls the bearing out from the shaft .
After dismantling all the parts of motor are clean with blower or brush the petrol may also be used if required. After its clamping all the part inspected deeply and all the essential points are noted in the record resister which may be required during assembling.
The winding are checked properly. if the winding are fully or burnt up the it is required to rewind the motor. Before rewinding not of all of the essential information about a winding.
4. Cleaning of a slots
After inspection if it is essential to rewinding the motor then the winding is taken out from the slot safely without giving any loss to the core. The instrument like tong, liver, hacksaw, pliers, etc, may be used for this purpose after taking out the winding the slots are clean and the pieces of insulation are taken up.
5. Maintenance of body
After cleaning, the motor body is maintaining. In this step all the joints are checked. If the internal surface of stator and outer surface of rotor are warmish. Thus the body is prepared.
6. Rewinding of motor
So now the motor is rewind according to the data’s collected during the dismantling. After rewinding both the stator and rotor they are properly warmish and the insulation resistance is chucked. If its value is not proper that the motor is dried again and again til the insulation resistance thus not common its proper value.
7. Assembling of motor
Now the motor is assembled again properly having full precaution. There must be no loss to any part of the at the time off assembling after assembling the motor, checked ,its insulation resistance again and its connection check the air gap between the stator and the rotor and test the motor and its proper operation. Thus the motor is over hauled and it is prepaid to reinstall on its place and to take the particular load.
So following these above steps we can prepare a dc motor.
Hence it is the main step of dc motor repair.
for knowing more about how to dc motor repair please sea this video.