DIN EN 50065-4-4:2003 頻率范圍為3KHz至148.5KHz的低壓電氣設備信令傳輸.第4-4部分:低壓退耦濾波器.阻抗濾波器
Signalling on low-voltage electrical installations in the frequency range 3 kHz to 148,5 kHz - Part 4-4: Low voltage decoupling filter; Impedance filter; German version EN 50065-4-4:2003