Features: _x000D_ _x000D_ _x000D_ This module give full consideration to the 485 bus lightning protection design and anti-interference design, high EMC and high performance of EMI; For outdoor long-distance transmission, the earth end of module is connected to the earth, that can have very good anti-interference and lightning protection, making the 485 bus more security;For indoor short-distance transmission, the earth end can be disconnected from earth. _x000D_ With standard 2.54 spacing pin header, it is convenient for your secondary development. _x000D_ With 120 ohm match resistor, short circuit of R0 can enable matching resistor; short circuit is suggested for long-distance transmission. _x000D_ It supports communication of multiple machines that the same network can be connected to at least 40 nodes. _x000D_ It supports hot plugging, while signal will not jam. _x000D_ Anti-interference type wiring and copper laying method prevent signal interference. _x000D_ Compatible with 3.3 V and 5.0 V signal, can match with module. _x000D_ With high performance of EMC and EMI. _x000D_ Using imported chip, industrial design, with strong anti-interference ability; using powerful 485 lightning protection design that can be used in industrial field and harsh environment; within the temperature of 40 to + 85 , the transmission distance can be up to 1km (tested with 850m 2*1.5 cable, it is suggested to use within 800 meters; please add repeater if more than 800 meters). _x000D_ With insulated wire and terminals, very convenient to use. _x000D_ Designed with RXD, TXD signal indicator lights for easy checking of sending and receiving status. _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ Specification: _x000D_ Wide voltage power supply: 3.0V ~ 30V _x000D_ Limiting voltage: 33 V( it is recommended to use within 30 V, the minimum voltage should be higher than 2.8 V) _x000D_ Size: 52 * 23 * 11mm / 2 * 0.9 * 0.4in_x000D_ _x000D_ _x000D_ _x000D_ Package list: _x000D_ 1 * Module_x000D_ 1 set * Cable