IEC 60317-26:1990 specifies the requirements of enamelled round copper winding wire of class 200 with a sole coating based on polamide-imide resin. Class 200 is a thermal class that requires a minimum temperature index of 200 and a heat shock temperature of at least 220 °C. The temperature in degrees Celsius corresponding to the temperature index is not necessarily that at which it is recommended that the wire be operated and this will depend on many factors, including the type of equipment involved. The range of nominal conductor diameters covered by this standard is:Grade 1: 0,071 mm up to and including 1,600 mm;Grade 2: 0,071 mm up to and including 0,500 mm.The nominal conductor diameters are specified in clause 4 of IEC 60317-0-1. This second edition of IEC 60317-26 replaces the first edition issued in 1988.