M91-2-R2C Unitronics M91 Textual display and keyboard HMI and PLC onboard I/Os expands up to 150 I/Os

Why Choose the Unitronics M91-2-R2C Micro PLC with Integrated Text HMI?

The Unitronics M91-2-R2C is a compact micro PLC with integrated text-based HMI from the Unitronics M90/M91 series. It combines programmable logic control, operator interface and onboard I/O in a single device, making it a practical and cost-effective solution for small and medium industrial automation systems.

The controller includes a built-in two-line LCD display with 16 characters per line and a 15-key operator keypad, enabling operators to view system data, navigate menus and enter parameters directly from the panel. This integrated design eliminates the need for a separate HMI panel while reducing panel space and wiring requirements.

The M91-2-R2C provides digital and analogue inputs with relay outputs for controlling industrial equipment. It also supports communication via RS232 / RS485 and CANbus, allowing integration with PLC networks, SCADA systems and remote monitoring solutions.

Key Features

• All-in-one PLC with integrated text HMI and keypad.
• 2-line LCD display with 16 characters per line.
• 10 digital inputs for sensors and control signals.
• 2 analogue inputs supporting voltage or current signals.
• 6 relay outputs for switching industrial loads.
• High-speed counter / encoder inputs for motion or measurement applications.
• RS232 / RS485 serial communication for industrial networking.
• CANbus support for distributed control systems.

Technical Specifications

• Manufacturer: Unitronics
• Series: M90 / M91
• Model: M91-2-R2C
• Controller type: Micro PLC with integrated text HMI
• Display: LCD text display
• Display size: 2 lines × 16 characters
• Keypad: 15 operator keys
• Digital inputs: 10 inputs
• High-speed inputs: up to 3 counter or encoder inputs
• Analogue inputs: 2 inputs (0–10 V, 0–20 mA, 4–20 mA)
• Relay outputs: 6 SPST-NO relay outputs
• Communication: RS232 / RS485 serial port
• Networking: CANbus support
• Programming capacity: approx. 36 kB ladder logic memory
• Supply voltage: 12 / 24 V DC
• Expansion capability: supports I/O expansion modules
• Mounting: Panel mount or DIN rail
• Protection rating: IP65 front panel
• Operating temperature: 0 °C to 50 °C

Typical Applications

• Small machine automation systems.
• Water treatment and pump control systems.
• Packaging and material handling machines.
• Industrial process monitoring and control.
• Standalone automation systems requiring basic operator interface.

Trusted by Automation Engineers

Unitronics M90 and M91 series PLCs are widely used in industrial automation because they combine PLC control and operator interface in a compact, cost-effective platform suitable for small and medium control systems.