UniOP ETOP308-U301 HMI Touch Panel – ETOP300 Series

UniOP ETOP308-U301: 5.7-Inch TFT Operator Panel in Distributed Control Architectures

The UniOP ETOP308-U301 is a panel-mount human-machine interface belonging to the ETOP300 product family, developed by UniOP S.p.A. (now part of the Gefran Group). Within a control loop, this unit occupies the operator layer — the boundary between field-level automation logic and human decision-making. Its 5.7-inch TFT color display, rated at 320 × 240 (QVGA) resolution, delivers sufficient pixel density for alarm banners, trend graphs, and multi-state indicator objects without imposing excessive processing overhead on the embedded controller.

Electrically, the ETOP308-U301 operates from a 24 VDC regulated supply, drawing a nominal current consistent with the ETOP300 platform’s power budget. The front panel carries an IP65 ingress protection rating, meaning it withstands dust ingress completely and resists low-pressure water jets — a specification that qualifies it for installation in wash-down zones, dusty machining environments, and outdoor enclosures with appropriate back-panel sealing. The resistive touch overlay responds to gloved-hand input, a practical requirement in manufacturing cells where operators wear PPE.

Communication is handled through RS-232 and RS-485 serial ports, supplemented by a USB interface for project upload and firmware maintenance. The RS-485 port supports multi-drop topologies at baud rates up to 115,200 bps, enabling the panel to reside on a shared serial bus alongside other field devices without requiring a dedicated point-to-point cable run to the PLC. The built-in driver library within the eSigner/Designer programming environment covers Siemens S7-200/S7-300 (via MPI/PPI adapter), Mitsubishi FX and Q Series (RS-422/RS-485), Omron C/CJ/CS Series (Host Link), Modbus RTU/ASCII, and Allen-Bradley DF1 — making the ETOP308-U301 a viable operator terminal across heterogeneous PLC environments without third-party gateway hardware.

Project development is performed offline in UniOP’s eSigner or Designer software suite, which compiles screen objects, tag bindings, alarm definitions, and communication parameters into a binary project file transferred to the panel via USB. This workflow decouples panel configuration from live PLC operation, allowing engineers to validate screen logic on a development workstation before commissioning. Existing project files from earlier ETOP308 firmware variants are generally forward-compatible, reducing reprogramming effort in like-for-like replacement scenarios.

The ETOP308-U301 is stocked at our Xiamen, China facility and ships globally via DHL Express, FedEx International Priority, and UPS Worldwide Expedited. Standard lead time from order confirmation to dispatch is 1–3 business days. All units are inspected for physical integrity and powered on for functional verification prior to packaging. A 12-month warranty against manufacturing defects is included with every shipment.

Real-time Stock & RFQ: [email protected] | WhatsApp: +86 18359268345

Technical Parameters

Hardware Logical Analysis

The ETOP308-U301’s hardware architecture reflects the design priorities of a mid-2000s industrial HMI platform: deterministic display refresh, robust serial communication, and tolerance for electrically noisy environments.

EMC Design: The panel’s metal enclosure functions as a Faraday shield, attenuating radiated emissions from the internal switching power supply and display backlight inverter. The RS-485 transceiver circuit incorporates common-mode choke filtering on the A/B differential pair, suppressing conducted noise induced by long cable runs through cable trays shared with motor drive wiring. Transient voltage suppression (TVS) diodes on the serial port lines clamp electrostatic discharge events to safe levels, protecting the UART controller from ESD damage during cable connection in live panels.

Resistive Touch Overlay: The four-wire resistive touch matrix operates independently of the display controller, with a dedicated analog-to-digital converter sampling the X and Y voltage dividers. This architecture means touch input processing does not compete with display refresh cycles for CPU time — a relevant consideration in screens with animated trend objects or high-frequency alarm updates.

Serial Port Isolation: The RS-232 and RS-485 ports employ optocoupler-based galvanic isolation between the panel’s internal logic ground and the field wiring ground. This isolation barrier — typically rated at 500 V or 1,000 V depending on the specific optocoupler selected — breaks ground loops that would otherwise inject 50/60 Hz hum or high-frequency switching noise into the serial data stream, causing framing errors and communication timeouts.

Flash Memory Architecture: Project data and firmware reside in separate flash memory partitions. This partitioning prevents a corrupted project file from overwriting the bootloader or firmware image, allowing the panel to recover to a known-good state via USB reflash without requiring factory service.

System Integration Benefits

• Multi-PLC Driver Library: The eSigner driver set covers Siemens, Mitsubishi, Omron, Modbus, and Allen-Bradley protocols natively, eliminating the need for protocol converters or OPC servers in mixed-brand installations.
• RS-485 Multi-Drop Topology: Up to 32 nodes can share a single RS-485 bus segment, allowing the ETOP308-U301 to coexist with remote I/O modules, drives, and other HMI panels on one cable pair — reducing wiring cost and panel space.
• IP65 Front Panel: Qualifies the unit for Zone 2 light-industrial wash-down and dusty machining environments without additional enclosure modifications, shortening installation engineering time.
• Offline Project Development: eSigner/Designer compiles and validates screen logic on a PC before deployment, enabling pre-commissioning testing and reducing on-site programming time.
• Project File Reuse: Existing ETOP308-series project files are generally forward-compatible, allowing direct reuse in replacement scenarios and avoiding full reprogramming costs.
• Glove-Compatible Touch Input: Resistive overlay responds to standard industrial gloves, maintaining operator usability in PPE-mandatory environments such as chemical processing and food production.
• Galvanic Serial Isolation: Optocoupler isolation on RS-232/RS-485 ports eliminates ground-loop interference, improving communication reliability in installations with long cable runs or shared cable trays.
• Deterministic Display Refresh: Dedicated touch ADC and display controller operate independently, ensuring screen refresh rates remain consistent under high alarm-event loads without input latency degradation.
• Compact Panel Footprint: The 5.7-inch form factor fits standard DIN-rail enclosure cutouts, preserving panel real estate in space-constrained control cabinets.
• USB Maintenance Port: Firmware updates and project transfers via USB require no serial adapter hardware, reducing field service tool requirements to a standard USB cable.

Quality Assurance & Global Logistics

Every ETOP308-U301 unit dispatched from our Xiamen facility is sourced from authorized distribution channels or verified OEM supply chains. Prior to packaging, each unit undergoes a power-on functional check: display illumination, touch calibration verification, and serial port loopback test. Units that do not pass this inspection are quarantined and not shipped.

Packaging uses anti-static foam inserts and double-wall corrugated cartons rated for international air freight handling. Shipments are dispatched via DHL Express, FedEx International Priority, or UPS Worldwide Expedited, with tracking numbers provided within 24 hours of dispatch. Typical transit times are 3–7 business days to Europe and North America, 2–5 business days to Southeast Asia and the Middle East.

A 12-month warranty against manufacturing defects is included. Warranty claims are processed via email with photographic evidence of the defect; replacement units are dispatched within 5 business days of claim approval. Documentation packages — including the original datasheet, wiring diagram, and eSigner software download link — are provided with every order at no additional charge.

Contact Information

Email: [email protected]
WhatsApp: +86 18359268345
Web: siemensplc.com
Location: Xiamen, China
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