Most industrial computer systems provide standard RS-232 serial ports. Though widely accepted, RS-232 has limited transmission speed, range, and networking capabilities. The RS-485 standards overcome these limitations by using differential voltage lines for data and control signals, which transparently converts RS-232 signals into isolated RS-485 signal without changing any hardware or software. The tM-7520A lets you easily build an industrial grade, long-distance communication system by using standard PC hardware.