IO-PT400 – Unitronics 4 PT100/NI100 inputs module

Why Choose the Unitronics IO-PT400 RTD Temperature Input Expansion Module?

The Unitronics IO-PT400 is a dedicated RTD temperature input expansion module designed to provide accurate temperature measurement capabilities for compatible Unitronics Vision and OPLC control systems. Featuring 4 RTD temperature inputs, the module enables reliable monitoring of industrial processes, HVAC systems, environmental controls and manufacturing equipment requiring precise temperature measurement.

Designed specifically for resistance temperature detector (RTD) applications, the IO-PT400 supports PT100, NI100 and NI120 sensors. The module offers high measurement accuracy and flexible wiring options, supporting 2-wire, 3-wire and 4-wire RTD configurations to suit a wide range of industrial installations.

With DIN rail mounting, integrated diagnostics and support for multiple RTD sensor types, the IO-PT400 provides a dependable solution for expanding temperature monitoring functionality within Unitronics automation systems.

Key Advantages

• Provides 4 dedicated RTD temperature inputs.
• Supports PT100, NI100 and NI120 temperature sensors.
• Compatible with 2-wire, 3-wire and 4-wire RTD connections.
• High measurement accuracy for industrial temperature monitoring.
• Simple integration with Unitronics Vision and OPLC systems.
• Compact DIN rail-mounted design saves control panel space.
• Suitable for industrial process control and environmental monitoring.

Key Features

• Unitronics IO-PT400 temperature input expansion module.
• 4 RTD analogue temperature inputs.
• Supports PT100, NI100 and NI120 sensors.
• 2-wire, 3-wire and 4-wire RTD compatibility.
• 40ms conversion time.
• Successive approximation conversion technology.
• Channel fault and out-of-range diagnostics.
• Communication and channel status LEDs.
• DIN rail or panel mounting options.

Technical Specifications

• Manufacturer: Unitronics
• Model: IO-PT400
• Product type: RTD temperature input expansion module
• Number of inputs: 4 RTD inputs
• Supported sensor types: PT100, NI100, NI120
• RTD wiring: 2-wire, 3-wire and 4-wire
• Conversion method: Successive approximation
• Conversion time: 40ms
• Input impedance: 10MΩ minimum
• Measurement accuracy: ±0.3°C typical (PT100)
• Maximum current consumption: 35mA from adapter 5V DC supply
• Typical power consumption: 0.19mA
• Protection rating: IP20 / NEMA 1
• Operating temperature: 0°C to +50°C
• Storage temperature: -20°C to +60°C
• Relative humidity: 10% to 95% non-condensing
• Dimensions (W × H × D): 80 × 93 × 60 mm
• Weight: Approximately 140 g
• Mounting type: 35mm DIN rail or panel mounting

Accurate Temperature Monitoring for Industrial Automation

The IO-PT400 enables automation engineers to integrate precise temperature measurement into PLC-controlled systems. By supporting multiple RTD sensor types and wiring methods, the module simplifies temperature monitoring across manufacturing, process control and building automation applications.

Its dedicated RTD inputs eliminate the need for external signal conditioning equipment, while built-in diagnostics help identify wiring faults, sensor failures and out-of-range conditions to improve system reliability and maintenance efficiency.

Typical Applications

• Industrial process temperature monitoring.
• HVAC and building management systems.
• Food and beverage processing.
• Water and wastewater treatment.
• Environmental monitoring systems.
• Manufacturing and production equipment.
• OEM machinery and automation systems.
• Heating and cooling control applications.

Trusted by Automation Engineers Worldwide

Unitronics temperature measurement modules are widely used in industrial automation systems where accurate process monitoring, reliable sensor integration and seamless PLC communication are essential for efficient operation.