Din Rail RS485 to WiFi Converters

Din Rail RS485 to WiFi Converters | Modbus RTU Serial to WIFI TCP Converter

  • Price:
  • $
  • Model:
  • USR-DR404
  • Quantity:
  • - +

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Product Name:Din Rail RS485 to WiFi Converters

  • Model:USR-DR404


RS485 to Wi-Fi/Ethernet Converter

USR-DR404 is a device that can realize data communication between RS485 and Ethernet/Wi-Fi. Through this device, the communication between the on-site serial device and the remote SCADA system can be realized. It integrates a wealth of network protocols like MQTT, TCP, UDP etc. and supports a variety of networking methods, suitable for various scenarios.

Ordering Guide

For serial to Wi-Fi/Ethernet convertor, PUSR offers 3 models to meet the needs of customers in different scenarios, and the main differences are shown in the table on the left.

Multiple Networking Options

The USR-DR404 provides a wealth of networking methods to meet customer networking needs.

• AP mode: Allow network devices to access USR-DR404 via Wi-Fi or Ethernet.

• STA mode: USR-DR404 as a network device accesses other networks via Wi-Fi.

• AP+STA mode: Work in AP and STA mode simultaneously.

• Bridge mode: The device connected to the Ethernet port of DR404 is equivalent to directly connecting to the upper-level network, and the DR404 is equivalent to being transparent.

• Router mode: The device connected to the Ethernet port of DR404 will be assigned an IP by the DR404.

Data Transmission Encryption

• Supports SSLTLS encryption in TCP cient, HTTP client and MQTT operation modes.

• Supports two-way certificates authentication.

Transparent Transmission Mode

Data is transmitted transparently between RS485 and Wi-Fi / Ethernet via TCP/UDP/HTTP Protocol, enabling data transfer between serial port device and network device.

Serial Command Mode

In this mode, USR-DR404 needs work as UDP Client or TCP Client, it allows users to send serial data to different servers. Data, server IP and port information should be included in the data packet sent by the serial device.

Addtional Features

  • • Modbus Gateway: Modbus RTU/TCP protocol conversion and multi-host Modbus polling.

  • • Heartbeat Packet Function: Remote server can detect abnormal disconnection from the client using this feature.

  • • Registration Packet Funciton: The server can identify different clients by usingregistration packets.

  • • Websocket Function: It can realize the real-time interaction between the serial device connected to DR404 and the web page on PC.

PUSR: Cloud SCDA Solution

PUSR provides a cloud-based SCADA system that allows users to upload data from field devices to the SCADA system for remote monitoring and data management to realize the potential of the equipment.

Industrial-Grade Design, High Reliability

  • • EFT Protection: Level 3, protect device against damage caused by instantaneous current interference in circuit, such as lightning stroke, power switch, etc.

  • • ESD Protection: Level 4, prevent electrostatic damage equipment, such as dust electrostatic, electric arc environment etc.

  • • Surge Protection: Level 3.

  • • Watchdog: Hardware & software dual watchdog to ensure stable operation without downtime.

  • • Wide Operation Temperature: -40℃~ 85℃

Product Details

  • • Dimension: 28.0*110.0*64.7 mm.

  • • Serial port: 1*RS485. Baud rate range: 300~230.4Kbps.

  • • Ethernet port: 10/100M MDI/MDIX, auto switch between cross and direct connection, 1.5KV electromagnetic isolation.

  • • Power Supply: 5~36V input, terminal block.

  • • Installation: DIN-Rail mounting.

  • • Reload button: In the case of forgetting the parameters, long press to restore the factory settings.

  • • Antenna Connector: 1*SMA-Female.

  • • Shell: PC+ABS material, V0 antiflaming

Shipping List

  • • 1*USR-DR404

  • • 1*Power Supply (5V/1A )

  • • 1*Power Adapter Cable

  • • 1*Wi-Fi Antenna

Smart Agriculture

The USR-DR404 combined with soil sensors can quickly and effectively acquire multiple sets of important data such as farmland soil temperature, humidity, pH, etc., which is convenient for users to adjust the management method in time, improve management efficiency, and create modern smart agriculture.

Medical Device Data Transmission Solution

The medical equipment transmits the entered data to the cloud server in real time through Wi-Fi network of DR404. Users can quickly complete the collection, storage and analysis of important data.


Port Number

1 Ethernet Ports: 1 x WAN/LAN


RX/TX: Max 4K bytes


2KV Electromagnetic isolation for Ethernet port

Speed Rate

10/100Mbps, MDI/MDIX





802.11 b/g/n




802.11b: +19dBm(Max.@11Mbps)

802.11g: +18dBm(Max.@54Mbps)

802.11n: +17dBm(Max.@HT20,MCS7)


User can configure power


802.11b: -89dBm(@11Mbps)

802.11g: -81dBm(@54Mbps)

802.11n: -73dBm(@HT20,MCS7)





485 interface (anti surge, anti thunder, overcurrent protection)

Input Voltage


Operating Temp







Network Mode






Work Mode

Transparent transmission/Serial command/

https Client/Modbus TCP<=>Modbus RTU


AT+ command

Networking Protocol


Max Client Numberin TCP Server Mode



Web server+AT command

Customer application software

Support customize application software

Email contact


Use WhatsApp

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