Certified AC-DC Motors Rewinding Mechanic

TABLE OF CONTENT

​

Fundamental terms used in AC winding

• Coil
• Turn
• Active side of a coil
• Inactive side of a coil
• Leads of a coil
• Pole pitch
• Coil pitch/span and coil throw
• Pitch factors
• Coil group
• Coil connections
• Pole connection
• Whole-coil winding
• Half coil winding
• Single layer winding
• Double layer winding
• Balanced winding
• Unbalanced winding
• Concentrated winding
• Distributed winding
• Partially distributed winding
• Fully distributed winding

DIFFERENT TYPES OF AC WINDINGS

• Basket winding
• Concentric winding
• Skein winding
• Flat loop Noon-overlapped winding
• Flat loop overlapped or chain winding
• Skew winding
• Diamond coil winding
• Involute coil winding
• Electrical degrees
• Phase displacement    

Table fan- terms- types of motors- winding details – data to be collected

• Terminology pertaining to table fan as per I.S. 555-1979
• Table type fan
• Rated voltage
• Rated speed
• Blade sweep
• Winding Shaded pole type table fan
• Capacitor motor
• Grouping of coils in table van
• Procedure of preparing winding table for capacitor type table van
• Determine the winding table for the arrangement of coils
• Winding capacitor type table van
• Data

Testing of windings

• Continuity test/resistance test
• Short circuit test/growler test
• Internal growler method
• Voltage drop method
• Ohmmeter method
• Polarity test
• Magnetic compass method
• Two screwdrivers method
• Polarity test by search coil method
• Unbalanced current test
• No-load test

Insulating and varnishing process in electric machines

• Air drying varnish
• Baking varnishes
• Thermosetting varnishes
• Solvent less varnishes
• Varnish thinners
• Preheating
• Impregnation process
• Varnish stripping
• End connections
• Method of coil connections
• Method of lead connections
• Shaping and binding the overhangs

Rewind a ceiling van

• Terminology used in ceiling fans
• Capacitors
• Suspensions system
• Earthing
• Insulation resistance
• Method of stripping the winding of the ceiling van
• Preparing the winding table for Ac single phase permanent capacitor type ceiling van
• Whole coil connection
• Winding calculations
• Determine the coil group
• Winding calculations
• Determine the coil groups
• Method of preparing former and winding coils
• Method if winding van motor
• Classification of insulation according to thermal class
• Cuffing
• Coil separator
• Wedge separator/paking strip
• Wedge
• Overhang inter-phase insulation
• Connections
• Slot liner Cuffing
• Coil separator
• Wedge separator/paking strip
• Wedge
• Overhang inter-phase insulation
• Connections

Single phase, split phase type motor winding (concentric coil winding)

• Split phase type
• Winding calculation and diagrams for concentric type winding

Winding a three phase induction motor – single layer distributed winding

• Distributed type winding
• Single layer winding
• Calculation for single layer distributed winding
• Method of overlapping
• Overhang Insulation
• End connections

Winding a three-phase induction motor – single layer concentric type – half coil connection

• 3-phase concentric winding
• Merits
• Demerits
• Grouping
• Grouping of coils

Winding a 3 phase induction motor- double layer distributed type winding

• Grouping
• Coil throw
• Winding sequence
• End connections
• Coil connections
• Placing of the coils in double layer winding

Starter for 3-phase induction motor, its necessity – basic contactor circuit- its parts and their functions.

• Necessity of starter
• Selection of starter
• Contactors
• Power circuit
• Control circuits
• Push-button actuation from one operating location
• Push-button actuation from two operating location
• Purpose of overload relays
• Magnetic overload relay
• Bimetallic overload relay
• Relay setting
• Tripping of starters
• No-volt coil
• Coil voltages
• Troubleshooting in contactor

Write a review