This standard applies to electrical equipment, excluding decoupling filters, using signals in the frequency range 3 kHz to 148,5 kHz for data transmission on low voltage electrical networks, either on the public supply network or within installations in consumers' premises.
It specifies requirements for mains communication equipment with respect to the load impedance of the mains.
It does not specify the impedance of external components that are not necessary for the normal functioning of the communication equipment.