What is Industrial Thermography?
Thermography is a non-contact measurement method in which thermal imaging cameras capture the infrared radiation of objects and display it as a colored thermal image (thermogram). In industry, thermography is used for early defect detection, quality assurance, and energy optimization.
In electrical systems, heat develops at weak points such as loose connections, overloaded circuits, or defective components. These problem areas are often detectable through elevated temperatures long before a failure occurs – this is exactly where thermography comes in.
💡 Important to know:
Thermography enables inspection under load during ongoing operations – without shutting down or touching the systems. Defects are detected before they lead to failures or fires.
Applications of thermography:
- • Electrical switchgear and distribution panels
- • Production machines and systems
- • Transformers and substations
- • Cable connections and busbars
- • Photovoltaic systems (module defects)
- • Motors, gearboxes, bearings
- • Process systems (temperature monitoring)
- • Building technology (energy losses)
VDI/VDE 2878: The Standard for Thermography
The VDI/VDE 2878 guideline is the authoritative standard for thermographic testing of electrical systems in Germany. It defines requirements for measurement methods, evaluation, assessment, and documentation.
Contents of VDI/VDE 2878:
- 1.Scope: Thermography on low-voltage, medium-voltage, and high-voltage systems
- 2.Qualification: Requirements for thermographers (Level 1–3 per DIN EN ISO 9712)
- 3.Measurement conditions: Minimum load 40% of rated load, steady-state operation
- 4.Assessment criteria: Temperature differentials and priority classification of anomalies
- 5.Documentation: Minimum content requirements for thermography reports
Assessment per VDI/VDE 2878 – Priority Classes:
| Priority | Temperature Differential | Actions | Deadline |
|---|---|---|---|
| Priority 1 | > 40 K | Immediate shutdown, acute fire hazard | Immediately |
| Priority 2 | 20–40 K | Short-term repair required | 1 month |
| Priority 3 | 10–20 K | Medium-term repair recommended | 3 months |
| Priority 4 | < 10 K | Monitor at next inspection | Next inspection |
💡 Important for assessment:
The temperature differential refers to the difference between the anomaly and comparable, intact components under the same load conditions. It is not the absolute temperature that matters, but the difference from the expected state.
What does thermography detect?
🔥 Loose connections
Increased contact resistance → heating → fire hazard. Most common cause of cable fires.
⚡ Overloaded circuits
Excessive currents → cable heating → insulation damage. Leads to short circuits.
🔌 Defective fuses
Corroded contacts → heating → tripping despite normal load. Production interruptions.
🔧 Asymmetric loading
Unequal phase currents → overloading of individual phases. Detectable through different temperatures.
⚙️ Defective components
Contactors, relays, motors → overheating indicates wear or defects long before failure.
🌡️ Cooling problems
Blocked ventilation slots, defective fans → overheating → premature failure.
Financial Benefits Through Preventive Thermography
Thermography is one of the most cost-effective methods for damage prevention. The investment in regular thermographic inspections pays for itself many times over through avoidance of failures, energy savings, and extended equipment lifespan.
1. Fire Prevention
Statistics: Fires caused by electrical defects
- • 30% of all industrial fires have electrical causes
- • Fire damage causes significant financial losses
- • Production downtime during reconstruction: 3–12 months
- • Loss of regular customers: 15–30% after extended outages
- • 70% of affected companies go bankrupt after a major fire
→ Thermography detects fire hazards before it is too late!
2. Avoiding Unplanned Downtime
Why unplanned downtime is so expensive:
- • High standstill costs per hour in production
- • Average downtime for unplanned defects: 8–48 hours
- • Emergency electrician on weekends/nights: hourly rate +100–150%
- • Express spare parts: 2–5x higher costs
- • Scrap due to production interruption
→ Unplanned downtime costs many times more than a preventive thermography inspection!
The investment in regular thermography pays for itself by preventing just a single failure!
3. Energy Cost Savings
Thermography uncovers energy losses that often go unnoticed:
⚡ Energy losses from defects
- • Loose connections: up to 15% losses
- • Overloaded cables: 5–10% higher consumption
- • Asymmetric load: 8–12% additional losses
- • Worn contactors: 3–7% more consumption
💰 Savings potential
By eliminating thermal defects:
- • Significant energy savings possible
- • ROI of thermography inspection: < 1 year
- • Long-term savings: cumulative over years
4. Extended Equipment Lifespan
Overheating is one of the main causes of premature failure of electrical components:
Effect of temperature on lifespan (Arrhenius rule):
- • Every 10 K temperature increase halves the lifespan of electrical components
- • A device at 80°C instead of 60°C lasts only half as long
- • Early detection and repair extends lifespan by 30–50%
→ Thermography extends the lifespan of your equipment and reduces investment costs!
5. Insurance Benefits
- Lower premiums: Many insurers offer discounts (5–10%) with proof of regular thermography
- Better protection in case of damage: Documented inspections demonstrate proper maintenance
- Faster claims processing: Inspection reports speed up assessment
💰 Overall savings summary:
For medium-sized companies, thermography offers significant savings potential:
- ✓ Energy savings: Significant annual reduction in electricity costs
- ✓ Downtime prevention: Considerable cost savings through preventive maintenance
- ✓ Insurance benefits: Possible discounts with regular inspections
- ✓ Extended lifespan: Reduced investment costs for replacements
→ The investment in thermography pays for itself within the first year!
Preventive vs. Reactive Maintenance
Switching from reactive (repair after failure) to preventive maintenance (repair before failure) is a decisive step towards cost reduction and operational safety. Thermography is the tool that makes this transition possible.
Comparison of Maintenance Strategies:
| Aspect | Reactive Maintenance | Preventive Maintenance (with Thermography) |
|---|---|---|
| Downtime | Unplanned, at the worst time | Planned, controlled |
| Repair costs | 2–3x higher (emergency service) | Normal (planned maintenance) |
| Production downtime | 8–48 hours | 0–2 hours (in maintenance window) |
| Spare parts costs | Express surcharges, uncertain availability | Normal prices, timely ordering |
| Consequential damage | Frequent (fire, further defects) | Rare (early detection) |
| Stress/urgency | High (crisis mode) | Low (plannable) |
| Total costs | 100% | 25–40% (!) |
💡 Practical example:
A production facility identified 12 critical hotspots through thermography:
- • Repairs were carried out as planned during the maintenance window
- • No production interruption
- • Avoided costs from unplanned downtime: many times the inspection costs
→ Significant savings through preventive maintenance!
6. Optimal Inspection Intervals
| System Type | Recommended Interval | Rationale |
|---|---|---|
| Switchgear (low/medium voltage) | 1 year | High load, critical importance |
| Production machines | 1–2 years | Vibrations, mechanical stress |
| Transformers, substations | 6–12 months | High power, critical for supply |
| Photovoltaic systems | 1–2 years | Module defects, yield losses |
| Office/administrative buildings | 2–3 years | Low load, less critical |
Conducting Professional Thermography
Professional thermography requires expertise, calibrated measuring equipment, and optimal measurement conditions. Only then are the results meaningful and legally usable.
Requirements for Measurement Conditions:
- 1.Load condition: At least 40% of rated load (preferably 60–80%) for meaningful measurements
- 2.Steady state: System must have been operating under load for at least 30 minutes
- 3.Accessibility: Clear line of sight to components being tested, cabinet doors open
- 4.Environmental conditions: Normal room temperature, no direct sunlight
- 5.Safety distances: Compliance with safety distances per DIN VDE 0105-100
Thermographer Qualification:
According to VDI/VDE 2878 and DIN EN ISO 9712, there are three qualification levels:
Level 1
Conducting measurements under supervision. No independent assessment.
Level 2 ✓
Independent execution, evaluation, and assessment. Minimum qualification for industrial thermography.
Level 3
Expert level, method development, training of other thermographers.
💡 AMA Systems Standard:
All our thermographers are certified at least Level 2 and have many years of experience in industrial thermography. Our thermal imaging cameras are calibrated according to DKD/DAkkS.
Thermography Inspection Process:
Preparation and Planning
Scheduling (during operating hours), clarifying access, providing system documentation. Ideally during normal load operation during regular production.
Visual Inspection On-Site
Recording of systems, checking accessibility, identifying critical areas. Verifying current load conditions (min. 40% rated load).
Thermographic Imaging
Systematic capture of all components with thermal imaging camera. Typically 10–30 thermograms per switchboard. Reference images of intact areas taken for comparison.
Evaluation and Assessment
Analysis of thermograms, calculation of temperature differentials, assessment per VDI/VDE 2878, prioritization of anomalies (Priority 1–4).
Report Generation
Creation of a thermography report with all thermograms, assessments, recommended actions, and deadlines. Delivered digitally and/or in print.
Follow-up Discussion
Explanation of results, recommendations for repair measures, prioritization by urgency and budget.
Time Required and Operational Disruption:
Advantages of thermography:
- ✓ No shutdown of systems required – measurement during operation
- ✓ No contact with live parts – safe
- ✓ Quick execution: Switchboard inspected in 10–15 minutes
- ✓ Minimal operational disruption: Production continues
- ✓ Flexible scheduling: Also possible during production
Documentation and Reporting
Professional thermography documentation is essential for traceability, legal protection, and as a basis for maintenance decisions.
Minimum Content of a Thermography Report:
- • Object data: System designation, location, contact person
- • Inspection date and time: Documentation of measurement conditions
- • Load conditions: Current load as % of rated load, current levels
- • Environmental conditions: Room temperature, humidity
- • Thermograms: All thermal images with clear identification
- • Assessment: Temperature differentials, priority classification per VDI/VDE 2878
- • Recommended actions: Specific measures with deadlines
- • Measuring equipment data: Camera model, calibration status, emissivity setting
- • Thermographer: Name, qualification, signature
Digital Thermography Documentation:
📱 QR Code Integration
- ✓ Direct access to thermograms
- ✓ Trend comparison across multiple inspections
- ✓ Automatic reminder for follow-up inspection
- ✓ Mobile access from smartphone
📊 Trend Analysis
- ✓ Comparison with previous measurements
- ✓ Detection of gradual deterioration
- ✓ Prediction of failures
- ✓ Optimization of maintenance intervals
Retention and Legal Significance:
Thermography reports should be retained:
- • At least 5 years: For trend comparisons and traceability
- • 10 years recommended: Liability protection
- • In insurance cases: As proof of proper maintenance
- • During audits and certifications: As quality documentation
Case Studies: Detected Damages and Prevented Failures
The following case studies show how thermography specifically prevents damage and saves costs:
Case 1: Loose Busbar in Main Distribution Board
Finding:
- • Temperature differential: +52 K
- • Priority 1 (acute hazard)
- • Loose busbar bolting
- • Signs of discoloration/tarnishing
Action & Result:
- • Immediate shutdown in next maintenance window
- • Busbar retightened, cleaned
- • Low repair costs
- • Prevented fire damage: potentially business-threatening
Case 2: Overload in Production Line
Finding:
- • Cable consistently +35 K warmer
- • Priority 2
- • Overload due to additional machines
- • Insulation damage expected
Action & Result:
- • Installation of additional circuits
- • Planned repair instead of emergency
- • Prevented production downtime
- • Additional energy savings
Case 3: Defective Contactor in CNC Machine
Finding:
- • Contactor overheated by +28 K
- • Priority 2–3
- • Worn contacts
- • Failure expected in 2–4 weeks
Action & Result:
- • Planned replacement in maintenance window
- • Minimal spare parts costs
- • Prevented unplanned downtime
- • Savings: significant standstill costs
Case 4: PV System with Module Defects
Finding:
- • 8 of 200 modules significantly hotter
- • Cell defects (hotspots in modules)
- • Performance loss approx. 4%
- • Fire hazard from hotspots
Action & Result:
- • Replacement of defective modules (warranty claim!)
- • No costs thanks to warranty
- • Yield increase through full performance
- • Fire hazard eliminated
💰 Overall balance of case studies:
- • Low thermography costs
- • Manageable repair costs through planned maintenance
- • Prevented damages: many times the investment
→ ROI: Extremely high – the investment always pays off!
Conclusion: Thermography as Key to Plant Safety
Thermography is one of the most valuable tools for preventive maintenance. It makes the invisible visible, detects problems before they become failures, and protects both people and equipment.
Key Benefits at a Glance:
🔍 Technical Benefits
- ✓ Measurement during ongoing operations
- ✓ No shutdown required
- ✓ Non-contact and safe
- ✓ Large-area coverage
💰 Financial Benefits
- ✓ Fire prevention
- ✓ No unplanned downtime
- ✓ Reduce energy costs (5–15%)
- ✓ ROI < 1 year
🛡️ Safety Benefits
- ✓ Early detection of fire hazards
- ✓ Employee protection
- ✓ 30% fewer fires
- ✓ Preventive maintenance possible
📈 Operational Benefits
- ✓ Higher system availability
- ✓ Plannable maintenance
- ✓ Extended lifespan
- ✓ Better insurance terms
When should you schedule a thermography inspection?
Act now if:
- • Your last thermography was more than 2 years ago
- • You experience frequent unplanned downtime
- • Your energy costs have risen unexplainably
- • You operate systems with high utilization
- • You want to reduce your insurance premiums
- • You want to establish preventive maintenance
What makes a professional thermography inspection?
- ✓Certified thermographers (Level 2 per DIN EN ISO 9712)
- ✓Calibrated thermal imaging cameras (DKD/DAkkS)
- ✓Assessment per VDI/VDE 2878 with priority classification
- ✓Detailed documentation with thermograms and recommended actions
- ✓Digital archiving with QR code access
- ✓Trend comparison with previous measurements
- ✓Personal follow-up discussion with explanation of findings
Frequently Asked Questions (FAQ)
Does the system need to be shut down for thermography?
No! That is the great advantage of thermography. Measurement takes place during ongoing operations under load – only then are defects detectable. Your production continues uninterrupted.
How often should thermography be performed?
Recommendation: Critical systems annually, standard systems every 2–3 years. After the first inspection, the optimal interval can be determined based on the results.
What does thermography cost?
Costs depend on the scope (number of switchboards, size of the system). Contact us for a free, non-binding quote – individually tailored to your operation.
Is thermography legally required?
Not explicitly, but DGUV Vorschrift 3 requires regular inspections of electrical systems. Thermography is the most effective method for detecting thermal defects and is recommended by VDI/VDE 2878.
Invest in thermography – protect your systems!
Thermography is a highly profitable investment in the safety and efficiency of your systems. The costs pay for themselves by preventing just a single failure.
Contact our certified thermographers for a non-binding consultation and an individual quote.
Standards & Regulatory References
Our thermographic inspections follow recognised industry associations and standards:
- VATh – German Federal Association for Applied Thermography – Quality standards and certification for thermographers
- DIN 54190 – Non-destructive testing: Thermographic testing (Parts 1–3)
- VDI 2878 – Application of thermography in maintenance
- DGUV Regulation 3 – Legal basis for inspection of electrical systems, complemented by thermography