The RS-C200ST range provides media conversion from RS-232, RS-422 and RS-485 serial to ST Multi-Mode or Single-Mode Fibre. They support speeds up 115Kbps for RS-232 and up to 500K for RS-232/RS-485 over extended distances of up to 2Km in Multi-Mode and 20Km in Single-Mode. Models are offered with either DB-9 serial connection or terminal block connection. Fibre is the perfect medium for extended distance RS-232/422/485. Unlike copper RS-232/422/485 cable runs, fibre is completely immune to electrical noise and therefore can cover much greater distances without any need to reduce transmission baud rates. The RS-C200ST supports 4 wire or 2 wire RS-485 operation, RX/TX 130 ohm line termination, and 1K ohm pull up/pull down resistors, all selectable via dip switches to ensure compatibility with virtually any Serial network. The RS-C200ST series media converter can be installed as a standalone unit or as a slide-in module to the 19" converter rack ( CR-1000 ) for use at a central wiring closet. Features: # 4 wire or 2 wire RS-485 operation # RX/TX 130 ohm line termination # 1K ohm pull up/pull down resistors