4DI 4DO Modbus RTU

Remote I/O

RS485-based with Modbus RTU protocol for easy integration with PLC, SCADA, and HMI systems.
4 optically isolated inputs and 4 digital outputs for reliable operation.
Supports half-duplex communication with cost-effective two-wire connectivity.
Offers robust communication, strong isolation, and industrial-grade reliability.
Ideal for factory automation, building control, and distributed monitoring applications.

Description

The 4DI/4DO Modbus RTU Remote I/O Module is an industrial I/O device designed for reliable digital signal acquisition and control in distributed automation systems. It supports Modbus RTU protocol over RS485 communication, allowing easy integration with most PLCs, SCADA, HMI, and DCS systems.

With 4 optically isolated digital inputs and 4 digital outputs, the module is ideal for monitoring switches, sensors, and controlling actuators or relays in real-time. It supports half-duplex communication with cost-effective two-wire connectivity, making it suitable for legacy industrial systems.

This device provides robust communication, strong electrical isolation, and industrial-grade reliability, making it suitable for factory automation, energy management, building control, and distributed monitoring applications.

Specifications

Input Power	Unregulated 9 – 24 VDC
Power Consumption	Less than 1 W @ 12 VDC
Protections	Reverse Polarity, Overvoltage (+/-35 VDC), Short Circuit, Transient Voltage, TVS/ESD
Indication	Power (Red), Status (Green)
Connector	5mm pitch screw terminal blocks
Enclosure	ABS Enclosure
Installation Type	Plug and Play
Dimensions	Modular Architecture (145mm x 90mm x 40mm)
Warranty	12 Months from date of installation or 18 Months from date of delivery (which ever is earlier)*

Data Connectivity

Connectivity Supported	RS485
Protocol Supported	Modbus RTU
Communication Interface	2 Wire Type
Watchdog Timer	System (5 Sec) and Communication
Indication	Green for Communication Status

Analog Input

Channels	8
Contact Rating	4-20 mA with 12 bit SAR ADC (Transient Protected) (80 dB CMRR)
Standard	Single ended 12 bit ADC

Digital Input

Channels	4
Contact Rating	24 VDC Sink/source (isolated) Upto 5000 VRMS for 1 minute
Standard	Digital Isolator type IEC 60950

Environment

Operating Temperature	0 to 65° C
Storage Temperature	-10 to 70° C
Operating Humidity	5 – 95% RH (non-condensing)

Mounting

Built Architecture	Modular
Mounting	DIN Rail Mountable, Wall Mountable, Stack Mountable
Installation	Plug and Play Device

Key Features

4 Optically Isolated Digital Inputs

Support source type connections for reliable signal acquisition.

4 Digital Outputs

Control relays, actuators, and other output devices.

Modbus RTU Protocol

Industry-standard protocol for seamless PLC and SCADA integration.

RS485 Communication

Half-duplex two-wire connectivity for cost-effective installations.

Optical Isolation

Protects against electrical noise and ground loops.

High-Speed Communication

Fast response time for real-time control applications.

Industrial-Grade Design

Rugged construction for harsh industrial environments.

DIN Rail Mountable

Easy installation in standard control panels.

Functional Description

Digital Input Channels can detect switch states, limit sensors, proximity sensors, or dry contact devices with optical isolation for noise immunity.

Digital Output Channels can control relays, solenoids, actuators, or other output devices based on Modbus RTU commands.

Modbus RTU Communication enables standard protocol-based data exchange with PLCs, SCADA systems, and HMI devices over RS485.

Optical Isolation provides electrical isolation between input/output circuits and the communication interface, protecting against voltage spikes and ground loops.

Configuration and Monitoring can be performed via Modbus RTU commands, allowing remote setup and real-time status monitoring.