EMB-2 Modbus Protocol Aware Server-0

EMB-2 Modbus Protocol Aware Server


In stock

SKU: EMB-2 Category:



The EtherModbus gateway allows serial Modbus RTUs to communicate and interoperate with Modbus/TCP based controllers. The Modbus standard protocol is an asynchronous protocol designed to connect directly to computer asynchronous ports. Modbus has been extended to operate over ethernet using the IP protocol suite. This gateway converts between the Modbus TCP/IP protocol and Modbus ASCII/RTU protocols transparently. The EMB-02 enables one or more MODBUS controllers to communicate with MODBUS ASCII/RTU based serial RTUs. It will not allow Modbus/TCP RTUs to operate with a serial MODBUS controller.

The Ethernet Modbus gateway contains two independent serial ports. Each may be configured as RS-232, RS-422, or RS-485 (2 or 4 wire). When configured for RS-485 4-wire, multiple RTU polling strings may be polled on each interface.

For other applications (point-to-point direct RS-232 links or point-to-multiple-points dialed links ) see the EtherPath single port serial server. The EtherPath uses TCP/IP.

A companion product, the EtherPoll is appropriate for applications using other protocols. The EtherPoll is protocol independent, and requires no knowledge of the RTU protocol. This allows it to work with any asynchronous byte-oriented protocol with no additional configuration. The EtherPoll uses UDP/IP. It’s data sheet is here.

The EtherGate is another companion product that is protocol-aware. It enables serial SCADA devices to communicate via an ethernet network. The EtherGate is ideal for transporting SCADA protocols via ethernet. To transport SCADA protocols over Frame Relay circuits (without ethernet), use the DCB BPF Scada-FRAD.



  • Configuration Methods
    • Any web browser
    • Telnet Menu Interface
    • Direct Connection Menu Interface
  • SNMP agent functionality ifaces (with bus-mastering on the 4-wire)
  • Serial speeds from 300 bps to 230,000 bps
  • RJ45 10/100BaseT ethernet,ncluded
  • Two serial ports, DE-9 (commonly called a PC DB-9) DTE interface, individually configurable
  • RS-485 two or four wire interface
  • Set up via telnet command line interface, the serial port, or any web browser
  • No Dip-switches… only one reset/setup button!


Six LEDs indicate LAN and port status


Press button for configuration

Data Port


  • Two serial ports, DE-9 (commonly known as a DB-9 PC connector) DTE interface, individually configurable
  • RS-485 two or for wire interfaces (with bus-mastering on the 4-wire)
  • Serial speeds from 300 bps to 230,000 bps

    LAN Connection

    Interface: 10/100BaseT autoselected


    • DIN rail or wall mount
    • 1 lb
    • 5mm x 78mm x 28 mm (W x H x D) 2.5 in x 3.25 in x 1.25 in (approximate)
    • 5-30 volt DC (external power supplies available for 110 VAC, 220 VAC, 48VDC, 125VDC and others)
    • 350ma @ 5 VDC, 200ma @ 12 VDC
    • Temperature Rated from -40 to +70 C, < 95% non-condensing humidity.

    Front view
    RS-232/422/485 Connector

    Rear view
    LAN and power Connectors

    Front view of Isolated Version



    • Integrating a new Modbus/TCP host into an existing Modbus RTU or Modbus ASCII network.
    • Extending the life of existing serial RTUs when installing a new Modbus/TCP host computer.
    • Interface between Modbus/TCP host network and wireless network connecting serial Modbus RTUs
    EMB-2R EtherModbus; Dual Port RS-232/485/422 Modbus/TCP to serial Modbus gateway
    (5-30VDC and 120 VAC power supply)
    EMB-2R-I EtherModbus; Isolated RS-422/485 Dual Port Modbus/TCP to serial Modbus gateway
    (5-30VDC and 120 VAC power supply)
    9501033 Optional 36-72 VDC Input Power Supply
    9501081 Optional 125 VDC Input Power Supply
    9902090 Optional DIN rail mounting clips

Additional information

Weight 2 lbs
Dimensions 5 × 5 × 5 in