[LNX-003M Rev2] RS-485 LAN Converter for Modbus HuMANDATA LTD.

[LNX-003M] RS-485 LAN Converter for Modbus (PoE/Non-PoE) Rev2


Possible to integrate Modbus TCP and RTU/ASCII networks
Easy configuration by microSD

Upcoming Product
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LNX-003M is a LAN converter which makes it possible to use Modbus RTU/ASCII devices via Ethernet local area network. LNX-003Me is an economy model of LNX-003M which only PoE function is removed.
LNX-003M has obtained the CE marking.(except for PoE function)CE


LNX-003M can convert protocols from Modbus TCP to Modbus RTU/ASCII. LNX-003M can connect Modbus devices over Ethernet by acting as masters or slaves. Although Modbus can be used for both serial and Ethernet devices, protocol conversions are also required to interconnect, because not only the physical connection of serial and Ethernet communications, but also the protocol is different. LNX-003M allows you to integrate Modbus TCP and Modbus RTU/ASCII networking.

You can use Lantronix Com Port Redirector (CPR) of the software that maps Virtual COM ports on a PC platform. It redirects application data destined to an attached device via the PC’s local serial (COM) port. Rather than going out the local port, the data is transmitted across the Ethernet network using TCP/IP. LNX-003e attached to the network receives the data and transfers it from its own serial port to the attached equipment.

LNX-003M supports PoE function as a standard model, making it possible to be powered via LAN cable (PoE compatible HUB or other is required).  It can also be operated from AC adapter. LNX-003Me is an economy model of LNX-003M from which only PoE function is removed. It requires AC adapter for power supply.
Network setting can be set by a microSD card. Restoring the setting information from a microSD card is very convenient when replacing LNX-003M.


  • Possible to control RS-485 devices via Ethernet local area network
  • Modbus TCP and Modbus RTU/ASCII protocols can be converted.
  • Supports Virtual COM port
  • Half-duplex / Full-duplex (auto detected)
  • Easy configuration by microSD
    • It is easily restored at the time of the exchange by microSD.
    • It can send configuration data by e-mail attachments.
    • It is setable in PC out of the network segment.
    • Backup of the configuration data is easy.
  • Configuration is possible via LAN by LNX SETTING TOOL
  • Possible power supply from the LAN cable by PoE function
  • Reliable industrial grade design
  • ESD and surge protection
  • Housing material: Plastic
  • DIN rail, magnet, and screw mountable (Attachment is required)
  • Includes a microSD card (with USB adapter)
  • Includes an AC adapter
  • RoHS and CE compliant CE(except for PoE function)

Connection example

[LNX-003M Slave Mode]

You can control remote Modbus RTU/ASCII slave devices via Ethernet.If the master is a PC, the IP address assigned to the LNX-003M can also be used by assigning it to the virtual COM port.

[LNX-003M Master Mode]

Modbus RTU/ASCII master device can communicate with remote Modbus TCP slave device via Ethernet

[Tunneling mode between two LNX-003M]

Direct communication between the two LNX-003M without PCs offers you to connect separated a RS-485 networks. By using cross cable, one to one connection is also available.


Item Description Remarks
Model LNX-003M/LNX-003Me  
Power 5VDC
Supplied by AC adapter or by LAN connector (PoE function)
(LNX-003Me is not supported the PoE function)
PoE function supports both mode A and B
Current Consumption Less than 350 mA  
Network Interface IEEE802.3(10Base-T)
half-duplex / full-duplex (auto detected)
LAN Connector RJ45 ESD protection
Isolation over 1500VDC
Protocol Modbus TCP  
Interface RS-485
Half Duplex Communication
(2 wire)
isolated from inner circuit (DC3000V)
ESD protection
Connector 5 position Terminal Block
5.08mm pitch
Memory Card microSD card For configuration
Baud Rate 300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200 bps  
Data Bits 7 or 8 bits  
Stop Bits 1 or 2 bits  
Parity Even, Odd, No parity  
Mode Modbus RTU Master/Slave
Modbus ASCII Master/Slave
Number of connectable devices (Slave Mode) Up to 8 Modbus TCP masters can be connected simultaneously  
Slave address - IP address table (Master Mode) Up to 8 IP addresses can be registered for each slave address (ID) range  
RX: Reception LED
TX: Transmission LED
SYS: System Status LED
LINK (RJ45 Connector): LINK Status
ACT (RJ45 Connector): ACT Status
Operating Ambient Temperature -10 to +55 °C No condensation permitted
Operating Ambient Humidity 30 to 85 % RH No condensation permitted
Storage Ambient Temperature -20 to +60 °C No condensation permitted
Storage Ambient Humidity 30 to 85 % RH No condensation permitted
CE Compliant EMS:EN61000-6-2
- IEC61000-4-2 Electrostatic discharge requirements
- IEC61000-4-3 Radiated electromagnetic field requirements
- IEC61000-4-4 Electrical fast transient burst requirements
- IEC61000-4-5 Surge immunity test requirements
- IEC61000-4-6 Conducted radio frequency requirements
- EN61000-6-4(2007)+A1(2011) Radiated Emissions
- EN61000-6-4(2007)+A1(2011) Conducted Emissions
This product has applied the common standard for industrial environment EN61000-6-2 and EN61000-6-4
(except for PoE function)
Weight Approx. 120 [g] Only main body
Dimensions 69 x 82.5 x 30 [mm]
(2.638" x 3.248" x 1.181")
Without projections

Interface Termianl (RS485 PIN ASSIGNMENT)

Pin No Signal Direction Notes

A (+)

I/O RS485 Data +

B (-)

I/O RS485 Data -
3 GND - Signal ground
4 A (+) I/O RS485 Data +
5 B (-) I/O RS485 Data -


This application makes configured data of the LNX series.

After saving the configuration data to the microSD, and insert the product it.
It will be automatically set by turning on the power of LNX-003M.
Then backup file is made to microSD card automatically.

Package Contents

  • LNX-003M or LNX-003Me
  • microSD card (with USB adapter)
  • AC adapter
  • Driver & Application CD

Price and Optional Accessories

Description MODEL Image List Price (JPY) Stock Status
RS-485 LAN Converter for Modbus
LNX-003M LNX-003M
RS-485 LAN Converter for Modbus
economy type Rev2
LNX-003Me LNX-003Me
Not supported
PoE function
Attachment with clamping screw
PEN-003 PEN-003
Attachment for 35mm DIN rail
Attachment with neodymium magnet
PEN-003-MG PEN-003-MG
5P Terminal to RJ45
Convert Adapter
ACC-005 ACC-005
Detachable 5P Terminal Connector
1757048 (Phoenix)
(Additional purchase)
© HuMANDATA LTD. - Altera & Xilinx FPGA Boards manufacturer in Japan - 2016