Electrical vs Mechanical Thermography

The Common Foundation

Both electrical and mechanical thermography use the same tool: an infrared camera that detects and visualises the heat radiated by objects. Both disciplines rely on the same physical principle — that faults generate heat before they fail, and that heat is detectable at the surface before damage becomes visible or audible.

The differences lie in what they are looking for, how they are conducted, and what standards govern the severity classification of findings.

Electrical Thermography in Detail

Electrical thermography surveys energised electrical distribution equipment while it is operating under load. The thermographer scans switchgear panels, distribution boards, motor control centres, transformers, busbar systems, and cable terminations, looking for temperature differentials that indicate fault conditions.

The physics is straightforward: any point of elevated resistance in an electrical circuit will generate heat proportional to the square of the current flowing through it (P = I²R). A loose termination, corroded busbar joint, or failing breaker contact all produce localised hot spots that are clearly visible in a thermal image when the equipment is energised.

Electrical thermography is the survey most commonly required by insurers and is the primary tool for demonstrating electrical maintenance compliance. It is conducted with the equipment energised and in normal operation — no shutdown is required.

Mechanical Thermography in Detail

Mechanical thermography surveys rotating and static mechanical equipment for friction, lubrication, and alignment faults. The thermographer scans bearing housings, coupling points, gearbox casings, belt and pulley systems, pump bodies, and motor frames while the equipment is running.

Mechanical faults generate heat through friction: a bearing that is under-lubricated, misaligned, or beginning to fail produces elevated temperatures at the bearing housing. This heat signature often appears weeks before the bearing becomes audible or before vibration analysis detects a developing fault — making thermography a valuable early-warning tool in rotating plant maintenance.

Mechanical thermography is particularly valuable for:

• High-value rotating equipment where unexpected failure is costly
• Equipment in remote or difficult-to-access locations where routine checks are infrequent
• Continuous process environments where unplanned downtime has high operational impact
• Equipment that has recently been serviced — to verify correct reassembly and lubrication

Do You Need Both?

For most commercial and light industrial facilities, electrical thermography is the primary requirement — it addresses the greatest fire risk, satisfies insurer requirements, and covers the largest proportion of critical assets.

For facilities with significant rotating plant — manufacturing, mining, processing, pumping stations, HVAC plant rooms, and similar — adding mechanical thermography to the survey programme provides substantially more complete coverage of the facility's failure risk profile.

Enisave Solutions conducts both electrical and mechanical thermographic surveys, typically in a single site visit, allowing comprehensive coverage with minimal disruption to operations.