When voltage changes occur in rapid succession, with magnitudes large enough to cause lighting level variations. The human eye-brain response is most sensitive to periodic r.m.s. voltage changes that occur at around 8 - 10 cycles per second.
Covered Conductor is extensively used in voltage up gradation projects ranging between 6.6KV to 33 KV. Covered Conductors are longitudinally water blocked and covered with special grades of materials that provide insulation and ultraviolet protection.
EXAMIANS