IO-DI8-TO8 – Unitronics 8 in / 8 out digital module

Why Choose the Unitronics IO-DI8-TO8 Digital I/O Expansion Module?

The Unitronics IO-DI8-TO8 is a reliable digital input and transistor output expansion module designed for use with Unitronics Vision PLC controllers. It extends automation systems by adding additional digital inputs for monitoring sensors together with high-speed transistor outputs for controlling external devices.

The module provides 8 digital inputs and 8 PNP transistor outputs, enabling PLC systems to interface with switches, sensors and pushbuttons while controlling loads such as relays, signal devices and electronic actuators. It operates using a 24 V DC nominal input voltage, making it suitable for standard industrial control systems.

Seven inputs operate as standard digital inputs while one input can function as a high-speed counter or frequency measurement input, capable of measuring pulse signals up to approximately 5 kHz. The module connects to the PLC via an expansion adapter and can be installed on a 35 mm DIN rail or mounted to a panel within a control cabinet.

Key Features

• 8 digital inputs for sensors and control signals.
• 8 PNP transistor outputs for high-speed switching applications.
• 24 V DC nominal input voltage for industrial automation systems.
• Inputs support PNP (source) or NPN (sink) wiring configurations.
• 1 high-speed counter input capable of pulse measurement up to approx. 5 kHz.
• LED indicators show real-time input and output status.
• Compatible with Unitronics Vision PLC expansion architectures.
• DIN-rail or panel mounting for flexible installation.

Technical Specifications

• Manufacturer: Unitronics
• Model: IO-DI8-TO8
• Product type: Digital input / transistor output PLC expansion module
• Digital inputs: 8 inputs (7 standard + 1 high-speed counter)
• Input type: PNP (source) or NPN (sink)
• Nominal input voltage: 24 V DC
• Supply voltage: 20.4–28.8 V DC (24 V nominal)
• High-speed counter: up to 5 kHz, 16-bit counting
• Outputs: 8 transistor outputs (PNP source)
• Output voltage: 12–24 V DC
• Maximum output current: approx. 70 mA per output
• Mounting: 35 mm DIN rail or panel mount
• Protection rating: IP20 / NEMA 1
• Operating temperature: 0 °C to 50 °C
• Typical dimensions: approx. 80 × 93 × 60 mm

Typical Applications

• Expansion of PLC digital I/O capacity.
• Monitoring switches, sensors and limit devices.
• Control of relays, signal lamps and electronic actuators.
• Machine automation and production equipment.
• Industrial control panels using Unitronics Vision PLC systems.

Trusted by Automation Engineers

Unitronics Vision I/O expansion modules are widely used in industrial automation systems to extend PLC monitoring and control capabilities while maintaining reliable machine operation.