commutation and interpoles, including: conditions for sparkless commutation and methods used to reduce sparking interpoles or commutating poles principles of commutation and advantages of interpoles resistance and electromagnetic field commutation current industry practices and technologies d.c. motor winding techniques calculations and insulation specifications, including: calculation of a half coil length and the amount of copper required commutators and identification of insulation specifications preparation of coils and equalisers preparation of copper prior to insulating coils and equalisers on armatures commutation and interpoles critical details and measurements when stripping a stator of a d.c. machine, including: lap winding with equalisers types of windings wave winding winding layout d.c. armature windings, including: lap and wave windings, progressive and retrogressive windings terms preparation for rewinding, including: checking the condition of a stripped core core loss test hot spots in armature core testing commutator before use removing of old winding principles and construction, including: construction of d.c. machine d.c. machine types types of armature windings, including parallel circuits value of generated electromagnetic field procedures and precautions required when inspecting, testing and/or re-using a commutator, including: coil position and commutator segment relationship commutator wear ring removal of armature leads on tungsten inert gas (TIG) welded commutator TIG welded and soft soldered commutators selection of appropriate insulation, including: B stage and VPI insulation dielectric strength, temperature rating, insulation properties, method of application and specific uses insulations used on the slot portion and overhang manufacturer recommendations reason for selecting a particular insulation simplex armature lap windings and wave windings, including: characteristics and applications commutator pitch number and position of brushes electrical power systems LV identification of insulation specifications relevant job safety assessments or risk mitigation processes relevant manufacturer specifications relevant safe working practices relevant WHS/OHS legislated requirements relevant workplace documentation relevant workplace policies and procedures simplex lap windings, including equalising connections for armature windings simplex wave windings, including dummy coils, comparison of lap and wave windings, and armature winding calculations sustainable energy principles and practices testing techniques, including continuity, insulation testing, use of ‘growler’ and magnetic field testing. |