Is the dS485 bus a SELV or PELV circuit? digitalSTROM Support October 05, 2018 07:33 Updated Follow The dS485 Bus is a SELV circuit, with an isolation voltage of 4kV. Related articles Can other deviced be linked to the dS-485 bus? Is it also possible to use 3-phase (400V) external conductors? What does the cabling look like if I have several sub-distributions in a single-family house? Can I use a free NYM cable or control line for the dS 485 bus?