In critical industrial processes—where a single moment of downtime can cause catastrophic losses (in safety, revenue, or compliance)—Industrial HMI Displays are the command center for monitoring and controlling operations. Redundant HMI displays take this reliability further: if one screen fails, a backup instantly takes over, ensuring zero interruption. This guide explores why redundancy matters for Industrial HMI Displays, key features of redundant systems, and how to implement them—helping industrial facilities safeguard critical processes.
Why Redundancy is Crucial for Industrial HMI Displays
1. Minimize Downtime in Critical Processes
Instant failover: Redundant HMI displays use “hot standby” technology—if the primary screen malfunctions (due to hardware failure, software crash, or power loss), the secondary display takes control in milliseconds. For example, in a chemical plant’s reactor control system, this prevents unmonitored pressure spikes or temperature drops during an HMI outage.
Compliance with safety standards: Industries like oil & gas, pharmaceuticals, and nuclear power must meet standards (Par exemple, IEC 61508, ISO 26262) that mandate redundancy for safety-critical systems. Redundant HMI displays help satisfy these requirements.
2. Protect Against Single Points of Failure
Component redundancy: Beyond dual displays, redundant systems often include backup power supplies, network cards, and processors. This means a failure in one component (Par exemple, a faulty power supply in the primary HMI) won’t take down the entire monitoring interface.
Data integrity: Redundant HMIs sync data in real time, so the secondary display always has the latest process data (Par exemple, valve positions, tank levels). If a failover occurs, operators see no gaps in information.
3. Enhance Operational Continuity
Planned maintenance without downtime: During scheduled HMI maintenance, the secondary display remains active—allowing processes to run while the primary unit is serviced.
Remote monitoring resilience: For facilities using remote HMI access (via SCADA systems), redundancy ensures operators can still view and control processes even if one networked HMI fails.
Key Features of Redundant Industrial HMI Displays
1. Hardware Redundancy Design
Dual display units: Two identical HMI screens (primary and secondary) are installed, often in side-by-side enclosures or redundant mounting setups.
Redundant I/O modules: Input/output modules (which connect the HMI to sensors/actuators) are duplicated, so a failure in one module doesn’t cut off data flow.
Automatic synchronization: The secondary HMI continuously mirrors the primary’s configuration, firmware, and data—ensuring both displays are always in lockstep.
2. Software for Seamless Failover
Failover logic: Embedded software detects failures (Par exemple, loss of communication with a PLC, screen blackout) and triggers the secondary HMI to take over.
Redundancy management tools: Software dashboards let operators monitor the health of both HMIs (Par exemple, “Primary HMI: En ligne, Secondary HMI: Standby”) and log failover events for troubleshooting.
3. Robust Connectivity
Redundant network paths: HMIs connect to control systems via dual Ethernet ports or redundant fieldbus connections (Par exemple, Profibus, Modbus). If one network link fails, the other keeps data flowing.
Wide protocol support: Redundant HMIs work with multiple industrial protocols (EtherNet/IP, PROFINET, Modbus TCP) to integrate with diverse PLCs and sensors.
Implementing Redundant Industrial HMI Displays
1. Assess Process Criticality
Identify critical processes: Focus redundancy on processes where downtime risks safety, regulatory fines, or major revenue loss (Par exemple, a refinery’s distillation column, a water treatment plant’s filtration system).
Determine redundancy level: Choose “hot standby” (instant failover) for the most critical processes; “warm standby” (secondary HMI boots up quickly after a failure) for less critical operations to balance cost and reliability.
2. Select Compatible Hardware and Software
HMI vendor compatibility: Ensure the HMI brand (Par exemple, Siemens, Rockwell, Schneider) offers redundant systems and that your PLCs/sensors are compatible.
Software licensing: Verify redundancy features (Par exemple, failover management) are included in your HMI software license—some vendors require premium licenses for redundancy.
3. Plan Installation and Testing
Physical setup: Install primary and secondary HMIs in easily accessible locations (for maintenance) and ensure adequate cooling/power (redundant power supplies are a must).
Failover testing: Regularly test failover by simulating primary HMI failures (Par exemple, unplugging power, disabling network). Verify the secondary HMI takes over without data loss or process disruption.
FAQs About Redundant Industrial HMI Displays
Q1: How much does redundancy increase the cost of Industrial HMI Displays?
A1: Redundancy typically adds 30–50% to the initial cost, but it’s offset by avoided downtime losses. For critical processes, the ROI (return on investment) is often rapid.
Q2: Can I add redundancy to existing (non-redundant) Systèmes HMI?
A2: In many cases, yes—vendors offer retrofittable redundant modules or software upgrades. Cependant, compatibility depends on the HMI’s age and model.
Q3: How do I monitor the health of redundant HMIs?
A3: Most redundant systems include dashboards or LED indicators on the HMIs showing “Primary/Secondary” status. Some also integrate with SCADA or CMMS (Computerized Maintenance Management Systems) for remote monitoring.
Q4: What’s the typical lifespan of redundant Industrial HMI Displays?
A4: Avec une maintenance appropriée, 7–10 years—similar to non-redundant HMIs, as redundancy focuses on failover, not extending individual component life.
Conclusion
Redundant Industrial HMI Displays are a cornerstone of reliability for critical processes, eliminating single points of failure and ensuring uninterrupted operation. By investing in redundancy, industrial facilities protect safety, comply with standards, and maintain productivity.
If you’re ready to implement redundant HMI displays (or need help assessing your process’s redundancy needs), Remplissez le formulaire sur notre site Web. Our industrial automation experts will analyze your setup and recommend tailored solutions for maximum uptime.
