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IO-DI8-RO4 – Unitronics 8 in / 4 out digital module
Unitronics IO-DI8-RO4 digital I/O expansion module featuring 8 digital inputs, 4 relay outputs, PNP/NPN compatibility and integrated 5kHz high-speed counter functionality for industrial automation systems.
£99.66
Why Choose the Unitronics IO-DI8-RO4 Digital I/O Expansion Module?
The Unitronics IO-DI8-RO4 is a compact and versatile digital I/O expansion module designed to extend the capabilities of compatible Unitronics Vision and OPLC controllers. Combining 8 digital inputs and 4 relay outputs within a single module, it provides a cost-effective solution for machine builders, control panel manufacturers and industrial automation engineers requiring additional field connectivity.
Designed for industrial automation environments, the IO-DI8-RO4 supports both PNP (source) and NPN (sink) input wiring configurations, allowing seamless integration with a wide range of sensors, switches and signalling devices. The relay outputs provide reliable switching of AC and DC loads, making the module suitable for control and monitoring applications across many industries.
With DIN rail mounting, integrated diagnostics and a built-in high-speed counter input, the IO-DI8-RO4 offers dependable performance for machine control, process automation and equipment monitoring applications.
Key Advantages
- Combines 8 digital inputs and 4 relay outputs in a single module.
- Supports both PNP and NPN sensor wiring.
- Integrated 5kHz high-speed counter input.
- Relay outputs suitable for AC and DC load switching.
- Compact DIN rail-mounted design saves panel space.
- Compatible with selected Unitronics Vision and OPLC systems.
- Status LEDs simplify troubleshooting and commissioning.
Key Features
- Unitronics IO-DI8-RO4 digital I/O expansion module.
- 8 digital inputs.
- 4 relay outputs.
- 24V DC operation.
- PNP (source) or NPN (sink) input compatibility.
- Integrated 5kHz high-speed counter on Input 7.
- 16-bit counter resolution.
- Communication and I/O status indicators.
- DIN rail or panel mounting options.
Flexible Digital Control and Monitoring
The Unitronics IO-DI8-RO4 enables engineers to expand controller capabilities by adding additional digital inputs and relay outputs without replacing existing PLC hardware. The module is ideal for connecting field devices such as sensors, push buttons, limit switches and control relays within industrial automation systems.
Its built-in high-speed counter functionality makes it suitable for pulse counting, encoder monitoring and frequency measurement applications, while the relay outputs provide reliable switching of motors, contactors, solenoids and other industrial loads.
Typical Applications
- Industrial machinery control.
- Packaging and assembly systems.
- Material handling equipment.
- Conveyor systems.
- OEM automation panels.
- Pulse counting and frequency measurement.
- Production line monitoring.
- Process automation systems.
Technical Specifications
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| Signal / Input Range | 24 V DC | |
|---|---|---|
| Product Series | Unitronics Vision I/O Expansion | |
| Device Type | Digital I/O Module | |
| Coil / Supply Voltage | 20.4–28.8 V DC | |
| Digital Inputs | 8 | |
| Digital Outputs | 4 | |
| Signal Type / Function | Digital | |
| Voltage | 24 V | |
| IP Rating | IP20 | |
| Product type | Digital I/O expansion module | |
| Digital inputs | 8 | |
| Input type | PNP (source) or NPN (sink) | |
| Nominal input voltage | 24V DC | |
| Input current | 6mA @ 24V DC | |
| Relay outputs | 4 | |
| Relay contact type | SPST-NO | |
| Maximum relay current | 5A resistive load | |
| Relay voltage | 250V AC / 30V DC maximum | |
| High-speed counter | 5kHz maximum | |
| Counter resolution | 16-bit | |
| Supply voltage | 20.4-28.8V DC (24V DC nominal) | |
| Protection rating | IP20 / NEMA 1 | |
| Operating temperature | 0°C to +50°C | |
| Dimensions (W × H × D) | 80 × 93 × 60 mm | |
| Weight | Approximately 164 g | |
| Mounting type | DIN rail or panel mounting |
Frequently Asked Questions
What is the Unitronics IO-DI8-RO4 used for?
The IO-DI8-RO4 expands compatible Unitronics PLC systems by adding 8 digital inputs and 4 relay outputs.
Does the module support both PNP and NPN sensors?
Yes, the digital inputs support both PNP (source) and NPN (sink) wiring configurations.
Does the IO-DI8-RO4 include high-speed counting functionality?
Yes, one input can function as a high-speed counter with frequencies up to 5kHz and 16-bit resolution.
What type of outputs are included?
The module provides 4 SPST-NO relay outputs capable of switching AC or DC loads.
How is the module installed?
The IO-DI8-RO4 can be mounted on a standard 35mm DIN rail or secured directly to a panel.
Trusted by Automation Engineers Worldwide
Unitronics expansion modules are widely used throughout industrial automation systems where dependable digital control, flexible I/O expansion and reliable long-term operation are essential for machine performance and productivity.
