An automated process for producing exposed electrical contact areas on the conductor part of an epoxy coated bus bar. When the epoxy coating is in the glassy state, one can safely and economically, preferably via automated apparatus, put the epoxy into the rubbery state by positioning the bar and applying localized heat at a select area of the coating; monitoring the heating to above the glass transition temperature of the epoxy, bringing cutting tools into contact with the epoxy for cutting and removing the rubbery coating away from the bus bar, and cooling the bus bar to bring adjacent coating back to the glassy state, thereby leaving an exposed electrical contact area of conductor on the bus bar with little or no surface damage.

An insulated wire having at least one layer of coating of the wire, comprising a thermosetting resin layer, at the outer periphery of a conductor, wherein the thermosetting resin layer is comprised of thermosetting resin layers having a laminated structure formed by coating and baking a thermosetting resin varnish; and wherein, in said laminated structure, an innermost layer having contact with the conductor comprises a thermosetting resin having an imide bond and is a layer having an average thickness of more than 5 μm and 10 μm or less; a method of producing the insulated wire; a coil; a rotating electrical machine; and an electrical or electronic equipment.

An automated process for producing exposed electrical contact areas on the conductor part of an epoxy coated bus bar. When the epoxy coating is in the glassy state, one can safely and economically, preferably via automated apparatus, put the epoxy into the rubbery state by positioning the bar and applying localized heat at a select area of the coating; monitoring the heating to above the glass transition temperature of the epoxy, bringing cutting tools into contact with the epoxy for cutting and removing the rubbery coating away from the bus bar, and cooling the bus bar to bring adjacent coating back to the glassy state, thereby leaving an exposed electrical contact area of conductor on the bus bar with little or no surface damage.

An insulated wire having at least one layer of coating of the wire, comprising a thermosetting resin layer, at the outer periphery of a conductor, wherein the thermosetting resin layer is comprised of thermosetting resin layers having a laminated structure formed by coating and baking a thermosetting resin varnish; and wherein, in said laminated structure, an innermost layer having contact with the conductor comprises a thermosetting resin having an imide bond and is a layer having an average thickness of more than 5 m and 10 m or less; a method of producing the insulated wire; a coil; a rotating electrical machine; and an electrical or electronic equipment.