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HP Partner

ES-320 Ethernet to Serial Device Server (Ethernet 1 Port RS422/485)


  • 1 port RS422/485
  • Max baud rate 1,000,000 (1 MegaBaud)
  • 10/100Base TX Ethernet port
  • User friendly interface, simple to use, powerful in operation
  • Web configuration and RFC2217 compliant interface
  • IP-30 rated enclosure
  • LED status indication
  • Optional DIN rail mounting kit
  • Serial Port Tunneling (individually configurable) allows serial cable replacement over any distance, no software required
  • Power supply included with screw fix connector (5-30V DC)
  • Simple operation for each and every operating system


Ethernet to Serial device server providing access to one RS422/485 serial port. Data transfer rates up to 1,000,000 baud, coupled with 1Mbit/s line drivers deliver uncompromising performance. Our ES range provides simple instant networked serial ports. RS485 - 1 twisted pair - half duplex configuration with autogating provides trouble free data transmission due to automatic control of data direction. A web interface allows secure configuration and control of the serial ports over a local network or the internet using any browser. For Windows our in-house designed (32 bit and 64 bit) driver gives you local COM ports, retaining existing software applications and allowing you to connect across your network to remote devices just as if they were attached locally. Serial Port Tunneling (individually configurable) allows serial cable replacement over any distance, no software required. You can access the device via TCP/IP sockets from any networked device like an Android tablet, PC or phone. On Windows OS TCP/IP sockets are handled by the Winsock API, this will differ on other OSs.

Windows Users - Our software drivers gives you local COM ports, allowing you to retain your existing software applications and connect to your devices over the network. COM Port can be assigned from COM1 to COM255 and the Brainboxes Ethernet to serial device remembers your COM Port assignment on reboots.
Web Interface Users (Linux/Apple OS/Android) - Alternatively access the device via TCP/IP socket from any networked device. Configure options via web interface.

Technical Specifications

LED Information

Status LED Green Device Ready
  Flashing Yellow Changing Settings
  Flashing between Red & Green Querying IP
  Flashing Green/Red User performing Hard Reset
  Flashing between Green & Red/Yellow IP address diagnostic
  Flashing between Green & Yellow Initialization diagnostic
Serial Port LEDs Green light on Port Open
  Flashing Green Data RX / TX
Network LED Green light on Link Established
  Flashing Green Data RX / TX


Ports 1 port RS422/485  
Connector DB9 Connector - 9 Pin Male  
Power Input 5 - 30V DC input, reverse polarity protected  
Power Consumption 0.77W (Typical)  

Port Settings - RS422/485

Baud Rate From 110 - 1,000,000 (1 MegaBaud)  
Data Bits 5,6,7 or 8  
Parity Odd, Even, None, Mark or Space  
Stop Bits 1 or 2  
Flow Control RTS/CTS, XON/XOFF  
Tx/Rx Modes RS422 Standard: RS422 allows one transmitter and up to 10 receivers with data transmitter rates up to 10
megabits per second for distances up to 40 feet and up to 100 Kilobits per second for distances up to 4,000
feet (1219 metres).
To achieve good long distance noise immunity, 2 wires are used to carry each signal, configured as a twisted
pair of cables. The TXD pair and RXD pair are used to carry the data whilst the RTS pair and CTS pair lines are
used for handshaking. Thus 2 twisted pairs are used without handshaking and 4 twisted pair cable is used with
handshaking both these schemes allow full duplex data communications.
RS485 Standard: RS485, based on the RS422 standard allows up to 32 driver/receivers pairs on a standard
load or 128 low load devices per port can be connected. Whilst only one of these should be transmitting data
at any time, the rest can all simultaneously listen to the data. Handshaking is performed by software protocol.
Two twisted pairs form a full duplex system.
Often only one twisted pair cable is used as the TXD and RXD lines are tied together; this is known as
half duplex mode. Brainboxes RS422/485 products implement a state of the art hardware autogating circuit
ensuring error free communications in half duplex configurations.

Port Settings - Ethernet

Data Rate 10/100 Mega bits/second  
Cabling Normal / Crossover auto-sensing (Auto-MDIX)  


Operating Temperature 0 to 55oc  
Storage Temperature -20 to 85oc  
Ambient Relative Humidity 5 to 95% (non-condensing)  
Housing IP-30 rated case  


Network Protocols ICMP, IP, TCP, UDP, DHCP, BOOTP, Telnet, HTTP, RFC2217  
Configuration Options Windows Utility, Web Interface  
OS Compatibility Microsoft Windows 7 32 bit & 64 bit Editions / Windows Server 2008 32 bit & 64 bit Editions / Windows
Vista 32 bit & 64 bit Editions / Windows Server 2003 32 bit & 64 bit Editions / Windows XP 32 bit & 64 bit
Editions / Microsoft Windows 2000 /Fully RFC2217 compliant / Interface for other OS’s & Linux
Connection to Network Ethernet 10BaseT / 100BaseTX  


Industry Approvals AEO C-TPAT Microsoft Certified Gold Partner WEEE RoHS EMC: CE TAA  
Microsoft Approvals Microsoft Certified Gold Partner  
Microsoft Signed Drivers Windows 7 32 bit & 64 bit Editions  
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