Thermal Vision: Enhancing Electrical Distribution Board Reliability Through Advanced Infrared Scanning at Hensoldt Optronics

As the electrical maintenance team at Hensoldt Optronics, we are the backbone, ensuring that every critical process, from specialised manufacturing to sensitive testing, receives stable and reliable power. The integrity of their Distribution Boards (DB boards) is non-negotiable. Any unexpected failure within these panels can trigger widespread system shutdowns and pose severe safety risks. Recognising the need to move beyond routine checks, our team drove a major initiative to deploy Infrared (IR) Thermography—a powerful diagnostic tool—to upgrade our maintenance approach from reactive repair to proactive prediction.

The Challenge: Detecting the Silent Killer

Electrical faults rarely happen without warning; they usually evolve from minor issues. These issues—a loose terminal lug, slight corrosion, or simple component wear—introduce increased electrical resistance into the circuit. This resistance generates heat, and this heat is the most reliable early warning sign of a problem.

The difficulty lies in the fact that this heat is invisible. Conventional inspection methods cannot reliably detect it:

• De-energised Inspection: We'd have to shut down production, and the cooling components would hide the fault.
• Load Checks: These confirm total current, but don't show the localised condition of individual internal connections where the fault is brewing.

Our team needed a system that allowed us to see the heat being generated under normal, full-load operating conditions—a non-invasive method to map the electrical health of the entire panel in real-time.

The Solution: Precision Infrared Thermography

The solution we implemented was high-resolution IR thermography. This non-contact technology captures infrared radiation and converts it into a visual thermal image, or a thermogram. This tool essentially gives our team an instantaneous Resistance Map of the electrical system.

We utilise specialised IR cameras capable of detecting minute temperature variances. This ensures even subtle signs of overheating are identified at an early stage. Our inspection focus areas include:

• Busbar Joints and Splices: These critical high-current junctions are primary candidates for loose connections.
• Cable Lugs and Termination Points: Checking the quality and tightness of the connection points.
• Circuit Breakers and Fuses: Identifying internal component failure or overloading.

By translating invisible heat into a clear, visual spectrum (from cool blue to hot white/red), we obtain immediate, undeniable visual evidence of an impending failure.

Methodology: Our Structured Approach to Predictive Maintenance

To maximise the effectiveness and safety of the IR scanning initiative, our team implemented a strict, four-stage protocol:

1. Inspection Under Load is Mandatory: All scans are conducted during peak operational periods. Since heat generation is load-dependent, maximum current flow provides the clearest possible thermal profile of any resistive fault.
2. Safety First Protocol: Our certified technicians always adhere to strict PPE and safety guidelines as the internal components are energised. Safety is our team's highest priority.
3. Delta-T (Delta T) Analysis: The Action Trigger: We don't just look at the absolute temperature. The core metric driving our action is the temperature difference (Delta T) between the faulty component and an equivalent, healthy reference component (e.g., comparing the hot phase to the cool phases on the same breaker).
   • Delta T of 1 to 10: Minor Fault. Logged and scheduled for correction during the next planned facility shutdown.
   • Delta T of 10 to 20: Serious Fault. Requires urgent scheduling for repair, typically within days.
   • Delta T of over 20: Critical Fault. Indicates imminent failure and a high fire risk. Requires immediate isolation and emergency repair.
4. Post-Repair Verification: A final thermogram is captured after any maintenance. This crucial step verifies the efficacy of the repair, confirming that the temperature has returned to the safe baseline and assuring the reliability of the fix.

Impact and Value Proposition for Hensoldt Optronics

The integration of infrared thermography has yielded immense practical value for Hensoldt, significantly elevating our electrical maintenance standards:

1. Enhanced Safety and Fire Mitigation

Our most significant achievement is the proactive elimination of severe fire hazards. By spotting connections exceeding the 20 Delta T threshold, our team has mitigated risks that were previously undetectable.

2. Reduced Unplanned Downtime

We have drastically minimised unplanned power outages. By identifying and correcting latent faults predictively during scheduled maintenance, we maximise operational uptime and protect critical manufacturing and testing schedules.

3. Targeted and Efficient Maintenance

IR scanning provides surgical precision. We can dispatch our technicians with exact instructions (e.g., "tighten the phase-A lug on Breaker 14"). This highly targeted approach reduces labour time, minimises component replacement, and maximises the efficiency of our resources.

4. Non-Invasive Diagnostics

The live, non-contact nature of the inspection means we gather vital data without ever disrupting production, which is a huge advantage in a high-throughput environment like Hensoldt.

Conclusion

The Thermal Vision project has solidified its place as a cornerstone of our facility management strategy. By leveraging the power of infrared technology, our team has successfully transitioned from reactive fixes to a truly predictive maintenance model. We have enhanced facility safety, extended the lifespan of critical electrical assets, and ensured the consistent, high-reliability power delivery that underpins Hensoldt Optronics' commitment to excellence. This proactive capability ensures our infrastructure is as reliable as the sophisticated products we help build