Usually both, with different jobs. The site’s M&E maintenance contractor knows the installation, holds the permits and opens the panels. A certified independent thermographer images every connection under load and writes the report. Keeping the inspection separate from the team that carries out the repairs means each finding is recorded as measured, for the operator, the client and the insurer.
What each side brings
The maintenance contractor brings the knowledge of the site: the single-line diagram, which side of a 2N system is carrying load, the change control process and the authorised person who opens each panel. The thermographer brings a radiometric camera in calibration, the training to read what it shows, and a reporting method that records the measured temperature, where it was taken, the reference it was compared with, the difference in °C and the load at the time.
Neither replaces the other. A survey without the contractor cannot get into the switch rooms safely. A survey without a trained thermographer produces images that are hard to defend later.
Why the report should stand on its own
A thermography report is evidence. Operators use it to show customers that the critical power path has been checked, and insurers and auditors read it to see what was found and what was done about it. That works best when the people recording the findings are not the people who will be asked to put them right, and when every reading can be traced to a location and a load.
Ti Thermal Imaging inspects and reports. We do not carry out remedial work, so there is no repair work for us to win from a finding. Your maintenance contractor investigates each finding with the circuit safely isolated, and carries out the work.
What certification to ask for
- The thermographer’s ITC certification level, and whether the company itself is certified
- A radiometric camera with a current calibration certificate
- Load recorded against each finding, not just a temperature
- Findings located precisely enough (board, way, phase, terminal) for the contractor to go straight to them
Our surveys are carried out by ITC Level 3 thermographers, and Ti is a Level 3 certified company. The difference between Level 1, 2 and 3 matters most on sites where the report has to stand up to scrutiny.
How it works on the day
The contractor’s authorised person opens one panel at a time under the site’s permit, the thermographer images it straight away, and the cover goes back on before the next one comes off. Phase currents are recorded at the same moment. The route follows the power path, from the LV switchboards through UPS, static transfer switches and busbar to the PDUs, planned with the contractor so that each side of a dual-fed system is seen carrying load.
Why it matters
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. Each one was located and passed to the installer before handover. The same separation applies on a live site: we record what we measure, and the contractor puts it right.
Frequently asked questions
Can our maintenance contractor do the thermography in-house?
Some contractors have trained thermographers on their team. What matters is the certification, a calibrated radiometric camera, load recorded against every finding, and a report that records findings as measured.
Does an independent thermographer need to work under our permit system?
Yes. The thermographer works under the site’s permit and change control, with RAMS provided before the visit, and never opens panels themselves.
How often should a live data centre be surveyed?
Most live data centres have an annual survey of the full power path, with extra surveys after a major load increase or a replacement. See how often a live data centre should be surveyed.
Related reading
- Data centre electrical thermography
- Busbar thermography at data centre commissioning
- UPS and switchgear surveyed live, without a shutdown
- Who opens the panels during a survey
- How a live data centre should prepare for a survey
- What happens after a survey finds a hot connection
- Annual PPM electrical thermography
- 7 electrical risks thermography finds
Ti Thermal Imaging’s surveys are carried out by ITC Level 3 thermographers, and Ti is a Level 3 certified company. Our work has featured on BBC News and ITV.
Talk to us: +44 20 3885 7464 · sales@thermalimaging.co.uk · contact page
About the author: Rachael Browning, General Manager, Ti Thermal Imaging.