包括在标称电压为6OO V、最大频率为2 OOO Hz、连续温度不超过28O°C（环境温度加加热）但可在有限时间内承受4OO°C的情况下使用的单铜导线电缆的特性。当电缆在110°C的火焰下燃烧5分钟时，将保持一定的介电强度。

Includes the characteristics of cables with single copper conductors, for use at a nominal voltage of 6OO V, a maximum frequency of 2 OOO Hz and a continuous temperature not exceeding 28O °C (ambient temperature plus heating) but which may withstand 4OO °C for a limited period. The cables will retain a certain amount of dielectric strength when subjected to a flame of 1 1OO °C for 5 min.