Serial to serial converters are designed to convert one serial protocol into another. Built for industrial applications, they also offer isolation and protection for electrical surges and noise. These serial converters accept power from the RS-232 connector or external 5 VDC power source.
The STS-1915S is a useful tool for connecting an RS-232 serial device to an RS-422 or RS-485 multi-drop network. And the reverse is true. Connect an RS-422 or RS-485 port to a standard RS232 port. It features a DB9 female connector (DCE) that connects directly to a standard RS232 port and a terminal block for wiring the RS-422/485 circuit. The STS-1920SI is a simple RS-232 to RS-232 repeater offering 2,500 Vrms 3-way isolation.