A system that includes low voltage power line subnet coupler that provides bi-directional communications between multiple power line subnets while substantially preventing the flow of power is provided. The system may include a power line communications device coupled to a first LV power line subnet, and a low voltage power line subnet coupler providing a data communications path between the first low voltage power line subnet and a second low voltage power line subnet. Additionally, some embodiments include a low voltage repeater communicatively coupled to the second LV power line subnet.