Should floor PDUs and remote power panels (RPPs) be included in a data centre thermography survey?

Yes. Floor-standing PDUs and remote power panels (RPPs) feed whole blocks of racks, and they can be imaged live with the IT load running. An authorised person removes the covers where it is safe, the thermographer images the incoming terminals, branch breakers and neutral and earth bars, and the load is recorded with each image.

Why floor PDUs and RPPs get missed

Surveys often cover the main switchboards and UPS in the switch room, then jump to the racks. The floor PDUs and RPPs on the data hall floor fall in between. They are owned by the hall rather than the switch room, they sit behind locked covers, and they look identical row after row. Yet each one carries the supply for a block of racks, and a single panel can hold dozens of terminations made at installation and rarely looked at since.

What gets imaged

The incoming supply cable terminations and the main incomer or isolator
The branch circuit breakers and the outgoing cable terminations to each rack
Neutral and earth bars, where neutral current can be significant (see neutral connections)
In a floor PDU with a transformer, the transformer cable terminations and the cubicle around it
Any metering or monitoring connections that are visible with the covers off

Each panel is recorded by the site’s own reference and feed (A or B), and each finding by breaker or terminal position, so the operations team can go straight to it.

Covers off, live, safely

The camera needs a direct view. Dead-front covers and panel doors are removed or opened by an authorised person under the site’s own permit and change process, and the thermographer works from a safe distance without touching anything (see who opens the panels). Where a cover can’t be removed with the panel live, the report says so: that panel is listed as not seen, rather than imaged through the cover and called clear.

Reading the results

Two traps catch out a quick survey. First, a transformer runs warm by design, so the warmth of its casing is not a finding in itself; what matters is how each connection compares with matching connections. Second, panels in a data hall sit in air that may already be warm. So each finding is reported as a measured temperature, the exact point where it was taken, the reference it was compared with (a matching breaker or phase under similar load) and the difference in °C. Branch breakers often carry very different loads, and the report allows for that rather than comparing a busy circuit with a lightly loaded one.

Load matters here as it does everywhere. Many halls run well below design load for years after handover, so we record the current at the time where the panel displays it and say plainly when a reading was taken at low load.

What the report gives you

For each finding: panel reference and feed, breaker or terminal position, a thermal and visual image, the measured temperature, the comparison and difference in °C, and the load at the time. Ti Thermal Imaging issues the report the same day. Ti inspects and reports; the site’s electrical team or contractor investigates and carries out any work.

The same approach runs through our commissioning work. 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. Imaging switchboards, busbar, floor PDUs, RPPs and rack PDUs as one survey gives the operator a single record of the whole power path.

Frequently asked questions

Does any IT load need to be switched off?

No. Floor PDUs and RPPs are imaged as they run. Nothing is switched, unplugged or touched by the thermographer.

Can floor PDUs be surveyed in the same visit as the switch room and racks?

Yes. Covering switch room, floor panels and racks together means the report follows the supply from intake to rack (see the whole power path).

How often should they be surveyed?

Most operators include them in the annual electrical thermography survey, with an extra visit when a hall’s load rises noticeably or new customers go live.