Classification of Insulating Material as per IS

Classification of Insulating Material as per IS Q. State the Classification of insulating material as per IS. No. Class Insulating Materials Uses 1 Y/ O Cotton, silk, paper vulcanized fibers wood PVC, VIR etc. Always used with impregnation. 2 A Cotton, silk, paper press, vulcanized fibers wood etc. Impregnated dielectric oil or varnish also some … Read more

Procedure for Cleaning, Washing and Drying of Insulation & Describe the Vacumm Impregnation Method of Varnishing

Procedure for Cleaning, Washing and Drying of Insulation & Describe the Vacuum Impregnation Method of Varnishing  Q. Explain the procedure for cleaning, washing and drying of insulation and describe the vacun impregnation method of varnishing. Methods of cleaning insulation : The failure of insulation takes place due to absorption of moisture. Oil, dust, dirt, excessive … Read more

Internal Causes of Failure and Abnormal Options of Equipments

Internal Causes of Failure and Abnormal Options of Equipments Q. What are the Internal causes of failure and abnormal operation of equipments. Internal Causes : In some unavoidable situation the machine may have to be run “over loaded” for a longer-period which causes temperature rise beyond the permissible limit.  During normal working shot-circuit may occur … Read more

Mechanical and Electrical Faults and Causes in Case of Electrical Machines

Mechanical and Electrical Faults and Causes in Case of Electrical Machines Q. list out the mechanical and electrical faults and causes in case of electrical machines. Mechanical Faults :  Sr. No. Fault Reasons Remedial measures 1 Bent shape Drawback in shaft coupling machine to machine or machine to load shaft. Concentric coupling very tight fitting … Read more

Causes of Heat in Bush-bearings of Electrical Machines

Causes of Heat in Bush-bearings of Electrical Machines Q. What are the causes of heat in bush-bearings of electrical machines ? Following are the causes of heat in bush-bearings : Worn out bearings / sleeves. Worn out shaft. Loss of lubrication. Mis-alignment of shaft pulleys couplings. Heavy vibration and noise due to uneven air-gap in … Read more