UT-218 is a converter with optoelectronic isolation. It complies with RS-232C, RS422, and RS-485 standards; it converts single side RS-232 signal to a balanced differential RS-422 or RS-485 signal. The built-in optoelectronic isolator can provide as high as 2,500Vrm isolated voltage; the fast instant voltage restraint is designed to protect RS-422/RS-485 interface; it adopts advanced TVS (TRANSIENT VOLTAGE SUPPRESSOR) instant voltage restraint; normally, TVS tube is in high impedance state; when both sides of TVS tube suffer from high power impact in a sudden, the voltage restraint will fast lower the impedance from both sides, and absorb in big current; with this, the voltage on both sides are fixed at presupposed value, protects the component of circuit from damage. This voltage restraint provides 1,500W each wire with lightning and ESD protection, and surge voltage and instant overvoltage protection on circuit which causing by all reasons; the tiny interelectrode capacitance ensures high speed transmission for RS-422/485 ports. RS-232 port connects with RS-232C standard port by DB9 female connector; RS-422/RS-485 adopts RJ-45 and DB9 male as connector. 

This converter is with built-in zero delay auto receiving and transmitting conversion and unique I/O circuit auto control data flow direction without any handshake signal (RTU, DTR); there is no need jumper wire setting for full duplex (RS-422) and half duplex (RS-485) mode, plug & play. It is compatible with current communication software and hardware, no need to set the previous working mode which base on RS-232.

UT-218 optoelectronic isolated converter provides connection for point to point, point to multipoint communication. For point to multipoint mode, each converter is allowed to connect 128 sets RS-422 or RS-485 devices with baud rate 300-115.2Kbps. The power and data flow indicators indicate the working status.

UT-218 User manual

UT-218 Datasheet