SPC X-Bus RS485 to Fiber Converters The FDX60 multimode fiber units allow the X-Bus transmission to be converted from 485 protocol to optical and back to 485. This allow the data between the SPC expanders to travel further distances. (max 4.5Km). It is recommended to use a maximum of 3 pairs per data channel or … Continue reading X-Bus to Optical Converters – COMnet