IEC 60317-68 Ed. 1.0 b:2017

IEC 60317-68:2017 specifies the requirements of enamelled rectangular aluminium winding wire of class 120 with a sole coating based on polyvinyl acetal resin, which may be modified providing it retains the chemical identity of the original resin and meets all specified wire requirements. The range of nominal conductor dimensions covered by this standard is
Wires of grade 1 and grade 2 are included in this part of IEC 60317 and apply to the complete range of conductors. The specified combinations of width and thickness as well as the specific ratio width/thickness are given in IEC 60317-0-9:2015.