IEC 60317-17:2010 specifies the requirements of enamelled rectangular copper winding wire of class 105 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 main change with respect to the previous edition is: - Clause 20: reference to the transformer oil resistance test method in IEC 60851-4.