Modbus RS485 Module

Modbus RS485 I/O System


Discontinued: No new product for sale. More Info

The Modbus RS485 I/O System provides an easy and cost-effective way to connect local digital and analog devices to any Modbus master, such as SCADA systems or PLCs. This system requires no configuration or network mapping, as each I/O module appears as a slave device on the Modbus network with a pre-configured data map. I/O modules are conveniently powered from the RS485 I/O Expansion module via the DIN rail mounted DataRail backplane. Up to 16 I/O modules can be added to one Modbus network, making it easy to add the devices you need. The system can also be used in conjunction with ProSoft Frequency Hopping radios for remote applications.


I/O Modules

Analog I/O 0-10 V Module

Analog I/O 4-20 mA Module

Digital/Discrete I/O Module


Click on image(s) to enlarge
Drag with the mouse. Click for close.

Features and Benefits

  • Easy to use: No software configuration required.
  • Easy to install: Mounts onto a 35 mm DIN rail without any tools.
  • Isolated: Each I/O Module provides field isolated inputs and outputs.
  • Scalable: Modbus RS485 I/O Module supports a multitude of I/O Modules. See specs for details.
  • Less wire clutter: Single power termination.
  • Flexible: the same I/O Modules can be utilized for wireless applications with Wireless I/O Radio Kit.
  • Works with Any RS485 Modbus Master / standalone system.
  • Customize I/O using Digital, 0-10 V, and/or 4-20 mA options.
  • 24-bit high-resolution Analog inputs.
  • Wiring label on each device for quick reference.
  • Color-coded labels for easy device identification.


Hardware & System



Unique Features

Works with any Modbus RS485 master device
 No software configuration required
 Single point power termination

Maximum Network Capacity*

Max capacity depends on I/O combination use Power Budget Calculator

I/O Module Slave ID Selection

16-Position rotary switch (+1 for Modbus slave ID)

DIN Rail Mounting Compatibility

35 mm x 7.5 mm DIN rail

DataRail™ (Included w/ Kit)

6.1 in / 156 mm - Supports up to Exp. +5x I/O modules. Other lengths also available.

Auto-Detection of Modules

Yes, via DataRail at power-up

DataRail Mounting Hardware

4-Claw attachment to 35 mm DIN rail with end terminal bracket

Built-In Mounting Hardware

Spring-loaded clip-on system

Wire Gauge

Solid / stranded (AWG) 28-12 gauge

Wire Rating

UL: 300 V RMS, 80 °C and 300 V, 105 °C
 CSA: 300 V RMS, 105 °C


2-Year limited

*When using more than a 5-Module Combination per system, use the Power Budget Calculator to determine maximum I/O Module capacity.

RS485 Expansion I/O Module




Baud Rate

9600 bits per second

Data Bits


Parity / Stop Bits

None / 1

Modbus Slave Addressing

Supports up to 16 addresses / I/O devices*

Red LED (Left)


Green LED (Right)

USB-ready (For firmware update)

Supply Voltage Range

9 to 30 VDC (± 5%)

Reverse Polarity Protection


Power Consumption

Typical: 20 mA / Max: 24 mA @12 VDC

Packaging Dimensions (WxHxD)

5.5 x 10.1 x 2.8 in / 140 x 257 x 72 mm

Net Dimensions (WxHxD)

0.7 x 3.9 x 4.5 in / 17.5 x 99 x 114 mm

Packaging Weight

0.8 lbs / 363 g

Net Weight

0.3 lbs / 136 g



Declaration of Conformity (RoHS/CE) 108.25 kB Last Modified 07/24/2018