EtherNet/IP to Modbus Serial 4 Port


The EtherNet/IP® to Modbus Serial gateway offers bi-directional data transfers between Modbus Serial and the EtherNet/IP network. Our EtherNet/IP Driver uses Class 1 I/O connections and/or Class 3 Message instructions. Protocol conversion gateways are the ideal solution for distributed networks when adding a remote rack becomes too costly.

The PLX31-EIP-MBS4 gateways are stand-alone DIN-rail mounted gateways that provide one Ethernet port for communication, allowing for remote configuration and diagnostics, and up to four (4) serial communication ports. The PLX30 gateways also come with an SD Card slot (SD card optional) for storing configuration files. In the event of a failure the SD card can be transferred to another gateway reducing downtime. These gateways also come with a wide input power range (10 Vdc – 36 Vdc), and an extended temperature range (-25°C to 70°C ). The PLX30 gateways include all the necessary cables required for communication.

A conformal coating option is available for this product.


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Features and Benefits

  • Data prioritization: Multiple I/O connections allow you to set RPIs for status and/or control data, optimizing Ethernet bandwidth. 
  • Includes an embedded EDS Add-On Profile, allowing for simplified integration and reduced commissioning time. 
  • Includes a SD card slot (SD card optional) for storing configuration files. This can be used for disaster recovery. 
  • Four serial ports allow for connectivity of up to 400 Modbus® devices, reducing the amount of gateways required for your application. 
  • ProSoft Discovery Service: This utility allows your PC to see the gateway and change its default IP address without being on the same subnet. 
  • Secure module configuration via module switch (v1.04 and greater). 
  • Up to 4000 16-bit registers can be used to exchange large amounts of data.




Power Supply

24 Vdc nominal
10Vdc to 36 Vdc allowed
Positive, Negative, GND Terminals

Current Load

24 Vdc nominal @ 300mA
10 to 36 Vdc @ 610mA maximum

Operating Temperature

-25°C to 70°C (-13°F to 158°F )

Storage Temperature

-40°C to 80°C (-40°F to 176°F )

Relative Humidity

5% to 95% RH with no condensation


IEC 60068-2-27; 15G @ 11ms, 3-Axis (Operational)
IEC 60068-2-27; 30G @ 18ms, 3-Axis (Non-Operational)


IEC 60068-2-6; 5G @ 10Hz to 150Hz

(Height x Width x Depth)

Standard: 5.38 in x 1.99 in x 4.38 in
(13.67 cm x 5.05 cm x 11.13 cm)

LED Indicators

Configuration (CFG) and Error (ERR) Communication Status
Power (PWR) and Hardware Fault (FLT)
Network Status (NS) EtherNet/IP Class I or Class III Connection Status
Module Status (MS) Module Configuration Status
Ethernet Communication Port Link/Activity and 100mbit
Serial Communication Port Receive (RX) and Transmit (TX)

Ethernet Port

10/100 Base-T half-duplex RJ45 Connector Electrical Isolation 1500 Vrms at 50 Hz to 60 Hz for 60 seconds, applied as specified in section 5.3.2 of IEC 60950: 1991 Ethernet Broadcast Storm Resiliency = less than or equal to 5000 [ARP] frames-per-second and less than or equal to 5 minutes duration

Serial Ports


Serial Port Isolation

2500 Vrms port signal isolation per UL 1577 serial port communication signal uses RF(Radio Frequency) modulation signal as isolation media, IC chip model is SiliconLabs Si844x(Si8440,Si8441,Si8442).

Shipped With Each Unit

2.5 mm screwdriver, J180 Power Connector,
(1 to 4) RJ45-DB9M Serial Adapter Cable (serial protocol),
(1 to 4) DB9 to Screw Terminal Adapter (serial protocol)


EIP Protocol Specifications

EIP Protocol Specifications

Protocol Specifications

EtherNet/IP Server

In server mode, the gateway accepts commands from one or more Clients to read/write data stored in the gateway’s internal registers.

Number of Connections


Supported PLC Types

PLC2, PLC5, SLC and ControlLogix file types supported

Internal Database

Data Table File Size: 100 or 1000 words

Data Table File Start: N10 to N109 (based on file size set to 100) or

N10 to N19 (based on file set to 1000)

CIP Services Supported

0x4C - CIP Data Table Read

0x4D - CIP Data Table Write

EtherNet/IP Client

In Client mode, the gateway controls the read/write data transfer between the gateway and other EtherNet/IP devices.

Number of Clients Supported


Command List

Support for 100 commands per Client, each configurable for command type, IP address, register to/from addressing and word/bit count.

Polling of Command List

User-configurable polling of commands, including disabled, continuous and on change of data (write only).

Other Configurable Parameters

Number of Commands (up to 100 per Client)

Min Command Delay

Response Timeout

Retry Count

Command Error Pointer

MBS Protocol Specifications

MBS Protocol Specifications

Protocol Specifications

Modbus Master

A port configured as a virtual Modbus Master actively issues Modbus commands to other nodes on the Modbus network. The Master ports have an optimized polling characteristic that polls slaves with communication problems less frequently.

Command List

Up to 100 commands per Master port, each fully configurable for function, slave address, register to/from addressing and word/bit count.

Polling of Command List

Configurable polling of command list, including continuous and on change of data, and dynamically user or automatic enabled.

Status Data

Error codes available on an individual command basis. In addition, a slave status list is maintained per active Modbus Master port.

Modbus Slave

A port configured as a Modbus slave permits a remote Master to interact with all data contained in the module. This data can be derived from other Modbus slave devices on the network, through a Master port, or from the module.

Node Address

1 to 247 (software selectable)

Status Data

Error codes, counters and port status available per configured slave port


Declaration of Conformity (ATEX) 348.50 kB Last Modified 10/28/2019
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