These Optic Fiber devices are designed to extend the RS485 or/and RS232 using the optic fibers. RS485 is a frequently applied differential serial communication standard in industrial automation, building control, and instrumentation networks. The most crucial aspect of any RS485 communication is the choice of cable, which will guarantee signal fidelity, data transmission reliability, and. The RS-485 Belden cables are the reference choice for automation systems, including Modbus, BACnet MS/TP, CANopen, or DMX512. Moxa's industrial-grade serial-to-fiber optic converters can convert RS-232/422/485 to optical fiber, which provides users with an easy and reliable way to communicate with their serial devices. Capable of extending the range of a RS485 communications link to 1Km minimum, typically 1mile.