What should an electrical thermography survey cover at a waste or recycling plant?

The fixed electrical plant that keeps the line running: the intake and main switchboard, motor control centres and VSD panels for shredders, balers, conveyors, trommels and separators, optical sorter supplies, and the boards for the yard, workshop and offices. It is surveyed live while the line is processing at normal throughput, because a quiet line shows very little.

Why throughput decides the result

Thermography shows heat at connections carrying current. On a recycling line the load follows the feed: a shredder or baler draws heavily when material is going through it and very little when it is idling. A survey booked for a maintenance day or a slow shift images motors and drives that are barely working. Agree the visit with the plant manager for a normal production shift, and the thermographer records the load at the time against every reading (see what load a survey needs).

What should be in scope

The intake and main LV switchboard, including any section added when the line was extended.
Motor control centres and VSD panels for shredders, balers, conveyors, trommels, eddy current and magnetic separators.
Optical sorter and air system supplies, including the compressor panels that feed the air jets (see compressed air plant).
Weighbridge, yard lighting, workshop and office boards.

Mobile plant, such as loaders and diesel shredders, sits outside an electrical distribution survey. So does the mechanical condition of bearings and gearboxes, which belongs to the site’s vibration and maintenance programme.

Planning the day on a working site

The site’s authorised electrician opens panels under the site’s own permit to work and dust rules, and the thermographer images each one straight away. Moving plant, tipping areas and conveyors mean the route through the building is agreed in advance, with the site’s PPE and walkway rules. Where a panel sits on a mezzanine next to the line, it is imaged while the line runs, with the electrician alongside.

Traps a good thermographer avoids

Motors and drives run warm by design. A VSD heatsink or a motor body being warm is not a finding. Readings are taken on electrical connections and compared like for like, phase to phase.
Load that comes and goes. A shredder’s current swings as material passes through. The thermographer images over a working cycle and records the load, rather than reporting a single snapshot as the whole picture.
Dust on surfaces. Heavy dust inside an enclosure changes how a surface reads and is noted as an observation, separate from the thermal findings.

What the report gives you

A same-day report from Ti Thermal Imaging that locates each finding by panel, circuit and phase, with the measured temperature, where it was taken, the difference in °C from a matching reference and the load at the time. Insurers of waste and recycling sites often ask how electrical plant is maintained, and the report is a clear record of what was checked. Ti inspects and reports; the site’s electrical contractor investigates with the circuit isolated and carries out any work.

What heavy load shows

Heat shows up when current flows. On a London data centre build, commissioning thermography by our team found 16 busbar sections reading above 80 °C under test load, the highest 103.5 °C at a tap-off unit, all located and imaged before handover. The same principle applies on a recycling line: survey it when it is working.

Frequently asked questions

Does the line need to stop for the survey?

No. It is a live survey, and it needs the line running at normal throughput.

How often should a recycling plant be surveyed?

Most sites survey annually, and again after a new line, shredder or baler is commissioned.

Can the survey be split across shifts?

Yes. Large sites are often surveyed area by area over more than one shift, as long as each area is running normally when it is imaged.