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Electrical Infrared Thermography
Nearly every electrical failure announces itself as heat first. Thermal imaging of energised equipment under load finds loose connections, overloads and imbalance while they are still a maintenance item — and produces a report your maintenance planner can actually work from.
The Problem
A connection does not fail all at once. It loosens, oxidises, or is torqued wrong at installation. Resistance rises. The joint dissipates heat, and the heat accelerates the oxidation, and the resistance rises further. The curve is slow for a long time and then it is not.
By the time that connection opens, the cheapest outcome is an unplanned outage. The expensive outcomes are a burned bus, a damaged breaker, or an arcing fault with somebody standing in front of it.
The same is true of the other things heat reveals: a circuit running above its rating, a phase carrying materially more current than its neighbours, a contactor with pitted tips, a fuse clip losing tension.
What Premier Does
We survey energised electrical equipment with a thermal imager under representative load, because a scan taken on a Sunday at 20 percent load finds nothing. We record the load at the time of inspection, so the temperature rise means something and so next year’s survey has something to compare against.
Every exception is captured as a thermal image and a matching visual image, identified to a specific piece of equipment, measured against a reference — ambient, the adjacent phases, or similar equipment under similar load — and assigned a severity and a recommended action.
Access is arranged with the plant in advance. Where covers must come off for the imager to see the connection, that work is coordinated with your maintenance department or an appropriately licensed electrical contractor and performed under your electrical safety program.
Coverage
Equipment We Inspect
Any accessible, energised electrical equipment carrying representative load:
- Switchgear
- Switchboards
- Motor control centers
- Panelboards
- Disconnect switches
- Dry-type transformers
- Oil-filled transformers
- Busway
- Bus plugs
- Feeder terminations
- Breakers & fused switches
- Contactors & starters
- Drive cabinets
- Capacitor banks
- Automatic transfer switches
- Generator connections
- UPS & battery terminations
- Control panels
- Motor terminal boxes
- Utility service equipment
What abnormal heat usually means
The most common finding by a wide margin. Typically shows as a single hot terminal with the conductor cooler than the joint.
The whole conductor run reads warm rather than a single point. Confirmed against measured current and the conductor rating.
One phase materially hotter across a length of bus or cable, corroborated with clamp readings on all three phases.
Pitted contactor tips, degraded fuse clips, breakers heating internally, and terminations that have been through a previous fault.
Heat that tracks back to the equipment being fed rather than to the distribution gear itself — a motor drawing more than it should, a stuck heater.
Undersized lugs, mixed conductor materials without the right connector, and terminations that were never torqued to spec.
The Deliverable
An Engineering Report, Not a Folder of Thermal Photos
A thermal image on its own is not actionable. Every exception in a Premier report carries the context a planner needs to schedule the work and the evidence an insurer or auditor will ask for.
| Each finding includes | Why it is there |
|---|---|
| Equipment identification | Designation, location and the specific component — so the electrician is sent to the right cabinet, not the right room. |
| Thermal image | The radiometric image with the measurement point marked. |
| Visual image | A matching photograph, because a thermal image alone rarely tells a tradesman which lug to look at. |
| Temperature data | Measured temperature, reference temperature and the rise, plus load at the time of inspection. |
| Severity classification | Rated against the temperature rise and the criticality of what it feeds. |
| Recommended action | Specific and scoped — what to inspect, retorque, replace or investigate further. |
| Priority | Immediate, next planned outage, or routine — so the list can be worked in order. |
| Suggested follow-up | Whether the item needs re-inspection, load verification, or a power-quality look before anyone starts replacing hardware. |
Verification
Once corrective work is complete, findings are re-imaged under comparable load and the result recorded against the original. A finding is closed on evidence — not on a work order being marked done.
Process
How a Survey Runs
Scope & Route
Agree what is in scope, walk the equipment list, and build an inspection route. Critical and hard-to-access equipment is identified up front so access can be arranged rather than improvised.
Load Confirmation
The survey is scheduled when the plant is running representative load. Equipment sitting idle cannot be meaningfully imaged, and a report that says so is worth more than one that pretends otherwise.
Field Survey
Thermal and visual capture of each item on the route, with current measurements taken where the thermal data needs corroboration. Anything that could not be inspected is recorded as not inspected, with the reason.
Analysis
Exceptions are evaluated against reference temperature, load, conductor and equipment ratings, and what the item feeds. Heat that is normal for the duty is not written up as a defect.
Report & Review
The report is issued and walked through with maintenance, so the priorities and the reasoning behind them are understood rather than just filed.
Coordination & Verification
Findings are scoped for repair and coordinated with appropriately licensed electrical contractors, then re-imaged after the work to confirm the condition has actually cleared.
Why It Matters
An infrared survey is one of the few maintenance activities that is performed with the plant running, requires no shutdown to gather the data, and routinely finds problems that would otherwise have surfaced as an outage. The economics are rarely close: the cost of a survey is measured against a single avoided unplanned stoppage.
It also produces something most plants do not otherwise have — a dated, imaged, measured record of electrical equipment condition. That record matters to insurers, to auditors, and to whoever has to justify the capital request to replace a forty-year-old switchboard.
Related
Often Runs Alongside
Schedule an Infrared Survey.
Tell us the size of the facility and roughly how many pieces of distribution equipment are in scope. We will come back with what a survey would cover and how long it would take on site.