Industrial Serial Server, RS485 to RJ45 Ethernet, TCP/IP to Serial, Rail-Mount Support

SKU: 20978
Part Number: RS485 TO ETH (B)
Brand: Waveshare


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Industrial serial server, RS485 to RJ45 Ethernet, TCP/IP to serial, rail-mount support
RS485 to RJ45 Ethernet Module

Rail-mount RS485 serial server

Features at a glance

This is a RS485 device data acquisitor / IoT gateway designed for industrial environment. It combines multi functions in one, including serial server, Modbus gateway, MQTT gateway, RS485 to JSON, etc. The module features RS485 and Ethernet ports, uses screw terminals for power input, supports 9~24V wide range power supply. Rail-mount flame-retardant case design, small in size, easy to install. It is suitable for applications like data acquisition, IoT gateway, safety & security IoT, and intelligent instrument monitoring...

Communication interface RS485, screw terminal, supports 32x slave devices
Power supply 9 ~ 24V DC, screw terminal
Dimensions L × W × H: 87 × 36 × 59 mm
Ethernet 10 / 100M auto-negotiation RJ45 connector, 2 KV surge protection
Serial port RS485 × 1: RXD, TXD, GND
Serial specification
Baudrate 300 ~ 115200 bps
Parity bit none, odd, even, mark, space
Data bit 5 ~ 9 bits
Flow control N/A
Configuration host, web browser, device management functions library
Communication method TCP/IP direct communication, VCOM
Operating mode TCP server, TCP client (coexisting with TCP server), UDP, UDP multicast
Environment requirement
Operating temperature -40℃ ~ 85℃
Storage temperature -45℃ ~ 165℃
Humidity range 5% ~ 95% relative humidity

Primary function

bi-directional transparent data transmission between RS485 and Ethernet

Rail-mount support

easy to combine multi rail-mounted serial server together, more freely

Modbus gateway support

suitable for Modbus gridding upgrade, can be used with 3D configuration software

Multi communication modes

supports TCP server / TCP client / UDP mode / UDP multicast

MQTT/JSON to Modbus

more flexible conversion between different protocols

When used as MQTT gateway, the devices can upload serial data to MQTT server by MQTT protocol through transparent transmission, supported servers including Baidu Cloud MQTT, Alibaba Cloud MQTT, China Mobile OneNet, etc. The acquired Modbus RTU or non-standard serial data can be parsed into JSON format and packaged into MQTTdata packet for uploading.

When used as JSON data acquisition gateway, the devices can be connected to data acquisition instruments through RS485 connection, then acquire data automatically, convert the data into JSON format, and finally post it to server. The acquired data supports Modbus RTU 645 instrument 97 version, 645 instrument 07 version, as well as sorts of non-standard RS485 protocols. The uploaded data format can be configured via host, and the JSON upload protocol can be MQTT protocol, HTTP POST protocol, HTTP GET protocol, and so on.

Multi hosts roll-polling support

different network devices will be identified and responsed respectively,
no more crosstalk issue while communicating with multi network devices

User-defined heartbeat/registration packet

easy for cloud communication and device identification

NTP protocol support

getting network time info for serial output or data upload

Multi configuration methods

supports Web browser configuration, obtaining dynamic IP via DHCP,
DNS protocol connected domain server address

Interface introduction
Outline dimensions
Resources & Services
Selection guide
Processor Cortex-M0 Cortex-M4 (up to 120MHz frequency) CH9121
Type RJ45 (10/100Mbps auto-negotiation)
Type UART RS485 RS232+RS485 (allows concurrent operation) UART
Baudrate 600bps~460.8Kbps 600bps~230.4Kbps 300bps ~ 115.2Kbps 600bps~230.4Kbps 300bps~921.6Kbps
Hardware flow NOT supported supported NOT supported
Data bit 5, 6, 7, 8
Stop bit 1, 2
Parity bit None, Even, Odd, Space, Mark
Interface protection
Power supply reverse-proof, ESD protection, anti-surge
Ethernet 1.5KV electromagnetic isolation
RS485 - 2KV ESD protection, 2.2KΩ pull up/down registers 2KV anti-surge 2KV ESD protection, 2.2KΩ pull up/down registers -
Other - - - lightningproof, over-current protection -
Operating mode
Type TCP Server, TCP Client, UDP Server, UDP Client, etc.
TCP Server customizable 1~16 Clients supports 30 Clients supports 2-ch Socket, 8 Clients per ch customizable 1~16 Clients
Features customized heartbeat packets, customized registration packets, customized webpage, RFC2217-like protocol, KeepAlive, timeout auto reboot, short connection, firmware upgrade via network KeepAlive, firmware upgrade via network
- - Modbus gateway, MQTT/JSON to Modbus Modbus gateway, Websocket (webpage to serial) -
Configuration Built-in webpage, Host computer config software, Serial commands Host computer config software, Serial commands
Power supply 3.3V/5V 5~7V 9~24V 5~36V 3.3V/5V
Operating current [email protected] [email protected] TBD [email protected] [email protected]
Operating temp. -25~75℃  -40~85℃ 
Storage temp. -40~105℃  -55℃~125℃

Weight: 0.077 kg

Quick Overview

  1. RS485 TO ETH (B) x1