Circuit shown in Figure 3-92. It uses dual-phase sequence protection relay sense. When the power positive phase sequence (U, V, w), following the electrical KA pull. If the pow
er supply phase sequence right, KA release, contact KM can not pull the motor does not work. Same time emitting diode VL light alarm. FIG transformer Ti, Tz becomes ratios of 100: 1 and 100: 3. A rated voltage of 380V, capacity is the number of VA.