... online, and improve the system's security. Applying very low frequency signal injecting and receiving technology, it greatly enhanced the ... capacitance and balance resistance, etc. Automatically match the best frequency. 5 frequencies automatically or manually selected. Receiver:Automatically determine ... ; 0-20KΩ@ system level is 24V.Transmitter:Output frequency:2Hz,1Hz,0.5Hz,0.2Hz,0.1HzShort circuit ...