Thermography on Electrical Panels

Method

1. Check load and safety conditions
2. IR inspection using IR windows or safe panel opening
3. ΔT comparison between phases/equivalent components
4. Priority classification and recommendations
5. Post‑maintenance verification

Ref.: NFPA 70B:2023 suggests at least annual inspection; more often for critical conditions.

Scope & typical use cases

Infrared inspection of live electrical assets finds the failure modes that develop silently under load: loose or oxidised connections on busbars and lugs, overloaded phases, failing breakers and contactors, and unbalanced loads that shorten equipment life. Because the survey is contactless and performed with the panel energised — ideally at 40–60% of rated load or higher — production does not stop while we work.

Typical engagements include annual whole-plant campaigns on LV/MV switchboards and motor control centres, targeted follow-ups after maintenance or retrofit work, insurance-driven inspections (many insurers now request periodic IR surveys per NFPA 70B-style programmes), and pre-shutdown screening so the maintenance window is spent fixing known hot spots instead of hunting for them. Where panels are equipped with IR windows we inspect without opening covers at all, which keeps arc-flash exposure and downtime near zero.

Each anomaly is classified by measured ΔT against the equivalent component on a comparable phase and load, so the maintenance team gets a prioritised list — repair now, plan within the month, watch at next survey — rather than a folder of thermal images to interpret.

How to judge a panel thermography survey

Two surveys of the same switchboard can produce very different reports. Before commissioning one, or when reviewing a report you already have, five points separate a usable result from a folder of images:

1. Who performed it: the thermographer's training and certification level in infrared thermography, and experience on energised electrical equipment
2. Load at the time of measurement: recorded per panel or circuit, because a connection that looks normal at low load can be a hot spot at full load
3. Measurement conditions: emissivity and reflected temperature settings, ambient temperature, and the correction applied when imaging through an IR window
4. Severity method: how each anomaly was classified, and against what reference (the equivalent component on a comparable phase and load, or an absolute limit)
5. Follow-up: a re-inspection after repair, so the report closes each finding instead of only listing it

For each anomaly, a report that can drive maintenance work states at least: the asset and exact component, an infrared image with a matching visible image, the load and ambient conditions at the time, the measured ΔT and its reference, the severity class and the recommended action. The method above follows the same logic: load and safety check first, ΔT against the equivalent component, priority classification, and a verification after maintenance. Surveys in hazardous areas add their own evidence requirements, covered in panel thermography evidence in Ex areas.

Deliverables

• PDF report with hot connections and severity
• IR/visible images with component markings
• Corrective actions (tightening, replacement, load redistribution)

Reference Standards

• NFPA 70B:2023

Related thermal inspection services

Panel surveys are often one route in a wider program. For motors, refractory, insulation, and process equipment, see industrial thermography inspection services. For a part-specific or permanently installed measurement setup, see custom thermal imaging solutions.