What should a data centre electrical thermography scope of works include?

A good scope lists the equipment by stage of the power path, from the transformer LV tails and main switchboards through UPS, static transfer switches, busbar and PDUs to the rack. It says when each stage is surveyed and under what load, who may carry it out (an ITC Level 3 thermographer), how access works, and exactly what the report must show and when.

Most data centre specifications give thermography one line: “carry out a thermographic survey of the electrical installation”. Every bidder then prices a different job. One images the main switch room in a morning, another walks every busbar run. The scope below is how we would write it, and what we ask for when a client sends us a one-liner.

1. List the equipment by stage of the power path

Intake and transformers: LV cable boxes and tails, and the link to the main switchboard. HV compartments are not opened live (see transformers in a data centre survey).
LV main switchboards, generator and ATS panels.
UPS input, output and bypass panels, and static transfer switches.
Busbar: rising and overhead runs, joints and every tap-off unit.
Floor PDUs, remote power panels and rack PDUs, sampled or in full – say which.
Mechanical and house supplies: chiller, CRAH and pump panels, BMS, security and fire panels.

Attach the single-line diagram and an asset list if you have one. A bidder who can count the boards can price the days honestly (see the whole power path, intake to rack).

2. Say when, and under what load

Thermography only shows a problem when current is flowing. At commissioning, tie the survey to the load bank test so busbar and PDUs are imaged while they carry test load. On a live site, survey on normal operating load and ask for the load at the time of each image to be recorded, so next year’s survey can be compared fairly. On a 2N site, say how the two sides will be loaded on the day (see commissioning vs annual survey).

3. Say who may carry it out

Ask for the thermographer’s certification level by name and a copy of the certificate with the bid. For data centre work we recommend ITC Level 3, because the person on site has to judge reflections, load and readings on equipment that cannot be switched off to check. Ask whether the thermographer is independent of the installer or maintenance contractor, and decide whether that matters for your project (see Level 1, 2 and 3 explained).

4. Write the access arrangements in

The thermographer images; the site’s authorised person opens covers under the site’s permit system. Name who provides that person, the working hours, any change-freeze dates and whether infrared windows are fitted. If a board cannot be opened live, the report should list it as not imaged, not quietly drop it (see who opens the panels).

5. Define the report

Every finding located by asset, termination and phase, with a thermal and visual image pair.
The measured temperature, where it was taken, the difference in °C from the matching reference, and the load at the time.
A list of everything surveyed with no finding, and everything not imaged and why.
Delivery time: we deliver same day. Whatever you choose, write it in.
A format that drops into the handover pack or CAFM system.

Ti inspects and reports. Any remedial work is carried out by the installer or maintenance contractor with the equipment isolated.

Why the detail 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. A scope that stopped at the main switch room would not have reached them before handover (see busbar thermography at commissioning).

Frequently asked questions

Should the scope cover every rack PDU?

Not always. Many sites sample rack PDUs at commissioning and survey every floor PDU and tap-off. The scope should say which, so bids are comparable.

Can one scope cover commissioning and the annual survey?

Yes. Write the commissioning survey as the baseline and the annual survey as the repeat, with the same asset list, so results can be compared year on year.

Should prices be per day or per asset?

Either works if the asset list is in the scope. Without it, a day rate is the only fair basis (see what affects the cost).