EDAM-8520U4 Isolated RS-232 to 4-CH RS-485 converter (Iso RS-232) * True RS-485 Star Wiring Hub * Surge protection on RS-485 line * The RS-485 Short-circuit protection * Isloated on RS-232 side * Auto direction flow control on RS-485 * Independent RS-485 driver for each channel * Transmission speeds of up to 115kbps or 6 Kbps (E-8520U4F) * Power and data flow indicator for trouble shooting