What is PLC? 

Power line communication (PLC) is a communication method that uses the local power grid (230V) to provide an internet connection to other Power line devices (charging stations). The PLC module is thus a communication converter, which converts wired internet connection (network cable) to the internet over the local power grid (power line). This removes the need to run network cabling to each charger.

Please use the link here for additional information from Zaptec