M91-2-R6C Unitronics M91 Textual display and keyboard HMI and PLC onboard I/Os expands up to 150 I/Os

Why Choose the Unitronics M91-2-R6C Micro PLC with Integrated Text HMI?

The Unitronics M91-2-R6C is a compact micro PLC with integrated text-based HMI from the Unitronics M90/M91 series, designed for small to medium industrial automation systems. By combining programmable logic control, operator interface and onboard I/O in a single device, it simplifies control panel design while reducing wiring and hardware requirements.

The controller includes a built-in two-line LCD display capable of showing 16 characters per line and a 15-key keypad, enabling operators to monitor machine status, view alarms and adjust parameters directly from the device without requiring an additional HMI panel.

The M91-2-R6C provides flexible onboard I/O including digital inputs, analogue inputs and relay outputs. It also supports serial and CANbus communication for integration with industrial networks, SCADA systems and distributed automation architectures.

Key Features

• Integrated PLC and text HMI in a compact automation controller.
• 2-line LCD display with 16 characters per line.
• 6 digital inputs configurable as PNP or NPN.
• 6 analogue inputs supporting voltage or current signals.
• 1 high-speed counter / encoder input for motion or frequency measurement.
• 6 relay outputs for switching industrial loads.
• RS232 / RS485 communication for PLC networking.
• CANbus support for distributed automation systems.
• I/O expansion capability for adding additional modules.

Technical Specifications

• Manufacturer: Unitronics
• Series: M90 / M91
• Model: M91-2-R6C
• Controller type: Micro PLC with integrated text HMI
• Display: LCD text display
• Display size: 2 lines × 16 characters
• Keypad: 15 operator keys
• Digital inputs: 6 inputs (PNP/NPN)
• Analogue inputs: 6 inputs (voltage or current)
• High-speed inputs: 1 counter / shaft-encoder input
• Relay outputs: 6 SPST-NO outputs
• Communication ports: RS232 / RS485 serial
• Network interface: CANbus support
• Programming capacity: approx. 36 kB ladder logic memory
• Supply voltage: 24 V DC
• Expansion capability: supports I/O expansion modules
• Mounting: DIN rail or panel mount
• Protection rating: IP65 / NEMA 4X (panel mounted)
• Operating temperature: 0 °C to 50 °C

Typical Applications

• Machine automation and OEM equipment.
• Water treatment and pump control systems.
• Industrial process monitoring.
• Packaging and material handling machines.
• Standalone automation systems requiring a simple operator interface.

Trusted by Machine Builders

Unitronics M90 and M91 PLCs are widely used in industrial automation because they combine programmable control and operator interface in a compact, cost-effective controller platform.