NB-IoT DF520 Bottom installation Ultrasonic Liquid Level Sensor
DF520 Ultrasonic Liquid Level Sensor is build through the NB-IoT module. it transmit the status via NB-IoT sim card to base station,then via internet network to network server to application server. Finally user can monitor the status remotely. It is optional for different frequency, such as Full frequency band( B1(2100MHz2), B3(1800MH2), B5(850MHz), B8(900MHz), B20[800MHz]]) and B28(700 MH2) and etc.