JWY-60, The 70,80 series static voltage relays without auxiliary power supply are static relays composed of imported integrated circuits. The measured AC voltage U - after passing through an isolated inverter, a voltage Ui proportional to the measured current is obtained in its secondary. After setting a fixed value, it is rectified, and the rectified pulse voltage is filtered by a filter to obtain a DC voltage Uo proportional to Ui. In level detection, Uo is compared with the DC reference voltage Ue. If the DC voltage Uo is lower than the reference voltage, the level detector outputs a positive signal to drive the output relay, and the relay is in an active state. Conversely, if the DC voltage Uo is higher than the reference voltage Ue, the level detector outputs a negative signal, and the relay is in a non active state
Classification and meaning of relay models

JWY-60、 70 and 80 series static voltage relays without auxiliary power supply