... , countryside, worksites, villages and pastures as electric power source STC Series generators are used in town, countryside, worksites, villages and pastures ... rotary field type, IP23, Insulation Class: B or F, adopting harmonic excitation system, safe and reliable using, easy operation and maintenance ... JB/T8981-1999. And in conformity to IEC34-1. STC series Three-Phase A.C.Synchronous Generator