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M91-2-R34 Unitronics M91 Textual display and keyboard HMI and PLC onboard I/Os expands up to 150 I/Os
Unitronics M91-2-R34 Micro PLC with integrated text HMI, featuring 20 digital inputs, 2 analogue/digital inputs, 12 relay outputs, RS232/RS485 communications and expandable I/O capability.
£569.73
Why Choose the Unitronics M91-2-R34 Micro PLC with Integrated HMI?
The Unitronics M91-2-R34 is a compact and powerful Micro PLC with integrated text-based HMI, designed to provide reliable machine control, operator interaction and industrial communications within a single cost-effective platform. As part of the trusted Unitronics M91 series, it combines PLC functionality, a built-in operator interface and onboard I/O, reducing panel space, wiring requirements and installation costs.
Featuring a built-in 2-line, 16-character LCD display and a durable 15-key keypad, the M91-2-R34 enables operators to monitor machine status, adjust parameters and access diagnostics directly from the controller. This integrated approach eliminates the need for a separate HMI whilst simplifying system design and maintenance.
With 20 digital inputs, 2 analogue/digital inputs and 12 relay outputs, the M91-2-R34 is ideal for industrial machinery, OEM equipment, building automation systems and process control applications. The controller also supports I/O expansion up to 150 points, providing flexibility for future system growth.
Key Advantages
- Integrated PLC and operator interface in one compact device.
- 2-line LCD display with built-in keypad.
- 20 digital inputs and 2 analogue/digital inputs.
- 12 relay outputs for versatile industrial control.
- Built-in RS232 and RS485 communications.
- Supports MODBUS networking and industrial integration.
- Expandable up to 150 I/O points.
- Reduces installation costs and control panel complexity.
Key Features
- Unitronics M91 Micro-OPLC platform.
- 2-line × 16-character LCD display.
- 15-key operator keypad.
- 20 digital inputs.
- 2 analogue/digital inputs.
- 12 relay outputs.
- 3 high-speed counter inputs up to 10 kHz.
- RS232 and RS485 communication ports.
- Real-time clock with battery backup.
- MODBUS and OPC server compatibility.
- DIN rail and panel mounting options.
- I/O expansion capability up to 150 I/O points.
Compact Control for Industrial Applications
The Unitronics M91-2-R34 provides a practical all-in-one automation solution for applications requiring multiple relay outputs and integrated operator control. By combining PLC logic, HMI functionality and communications within a single unit, it reduces hardware requirements whilst simplifying installation and commissioning.
Its combination of digital and analogue inputs, extensive relay outputs and communication capabilities makes it suitable for machinery control, building automation, pumping systems, HVAC installations and general industrial automation projects. Expansion capability ensures the controller can adapt as system requirements grow.
Typical Applications
- Water and wastewater treatment systems.
- HVAC and building automation.
- Pump control and booster stations.
- Packaging and labelling machinery.
- Material handling systems.
- OEM equipment and machine automation.
- Industrial process control.
- Standalone automation systems.
Technical Specifications
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| Device Type | HMI + PLC | |
|---|---|---|
| Product Series | Unitronics M91 | |
| Touch Technology | Keypad (non-touch) | |
| Communication | RS232, RS485 | |
| IP Rating | IP65 | |
| Series | M91 | |
| Product type | Micro PLC with integrated HMI | |
| Power supply | 24 V DC | |
| Digital inputs | 20 | |
| Analogue/digital inputs | 2 | |
| Relay outputs | 12 | |
| High-speed counter inputs | 3 × 10 kHz | |
| Display | STN LCD, 2 lines × 16 characters | |
| Keypad | 15 keys | |
| Communication ports | RS232 / RS485 | |
| Program memory | 36K virtual ladder memory | |
| Database capacity | 1024 integers | |
| Expansion capability | Up to 150 I/O points | |
| Protection rating | IP65 / NEMA 4X when panel mounted | |
| Operating temperature | 0°C to 50°C | |
| Weight | Approx. 420 g | |
| Mounting type | DIN rail or panel mounting |
Frequently Asked Questions
What is the Unitronics M91-2-R34 used for?
The M91-2-R34 is used for industrial automation applications requiring compact PLC control, integrated operator interaction and multiple relay outputs.
How many inputs and outputs does the M91-2-R34 provide?
The controller includes 20 digital inputs, 2 analogue/digital inputs and 12 relay outputs.
Does the controller include an HMI?
Yes. The M91-2-R34 features a built-in 2-line LCD display and 15-key keypad for local operation and monitoring.
Can additional I/O modules be added?
Yes. The controller supports expansion modules and can be expanded up to approximately 150 I/O points.
What communication interfaces are included?
The controller includes RS232 and RS485 communication ports and supports MODBUS networking for integration into industrial control systems.
Trusted by Industrial Automation Professionals
Unitronics M91 Micro-OPLC controllers are widely used in industrial automation, building management and OEM machinery applications, providing dependable control, integrated operation and cost-effective system design.
