Power quality and infrared thermography in Toronto
A loose lug runs hot for months before it fails, and an unstable supply sends a UPS to battery or bypass with no outage on record. Infrared thermography finds the first with the equipment under load. A power quality survey finds the second by recording the supply for several days. Both cover the UPS and what feeds and follows it: PDUs, panels, switchgear and transfer switches.
Key facts
- Thermography interval: every 12 months, every 6 months for equipment in poor condition (NFPA 70B)[1]
- NFPA 70B: a standard, not a recommended practice, since 2023[2]
- Canadian framework: CSA Z463, maintenance of electrical systems[3]
- Done under load: no shutdown; covers open only where safe and permitted
What Does Thermography Find on a UPS and Its Switchgear?
Heat where heat should not be. A loose lug runs hot for months before it fails, and an infrared camera sees it while the equipment stays under load: loose lugs and overloaded phases at the UPS terminals, a loose inter-cell link or a high-resistance block in the battery string, failed fans on the power modules, worn contacts and loose bus joints in the switchgear. NFPA 70B lists thermography of all equipment every 12 months, and every 6 months when equipment is in poor condition. Each finding comes with the images, the temperature difference, the load and a priority; a re-scan after the repair proves the fix.
In this video
- 0:00 What does thermography find on a UPS and its switchgear?
- 0:19 Where does it look?
- 0:47 What does the power quality survey catch?
- 1:12 When do you book them?
- 1:41 Talk to Symetrix Canada
Transcript
What does thermography find on a UPS and its switchgear? Heat where heat should not be. A loose lug runs hot for months before it fails, and an infrared camera sees it while the equipment stays under load. Connections carrying the same current should run at the same temperature, so a terminal running hotter than its neighbours is the finding.
Where does it look? The UPS input, output and bypass terminals, where loose lugs and overloaded phases show first. The battery string, where a loose inter-cell link or a block with high internal resistance runs hot. The power modules and capacitors, where failed fans and cooling paths show. And the distribution around it all: PDU and panel breakers with overloaded circuits, switchgear and transfer switches with worn contacts and loose bus joints.
What does the power quality survey catch? A recorder sits at the UPS input for several days, logging voltage, current, frequency, harmonics, sags, swells and transients. It answers what one visit cannot: why the UPS went to battery or bypass when nothing else noticed, whether the generator holds voltage well enough for the UPS to accept it, and whether harmonics are heating the neutrals.
When do you book them? NFPA 70B, a standard since 2023, lists thermography of all equipment every 12 months, and every 6 months when equipment is in poor condition. The other triggers: after a fault or a transfer nobody can explain, and during a load bank test, when every connection carries full current. Each finding comes with the images, the temperature difference, the load at the time and a priority, and a re-scan after the repair proves the fix.
Book the scan in the same window as your UPS visit. Symetrix Canada services UPS systems across Toronto, the GTA and Ontario, with an around-the-clock emergency line. Reply and quote within 4 business hours. Call 1 (438) 800-0382. Find Symetrix Canada on the web.
Infrared thermography
Connections carrying the same current should run at the same temperature. A terminal hotter than its neighbours on the same circuit points to a loose, corroded or undersized joint, or a phase carrying more than its share.
| Where | What shows up hot |
|---|---|
| UPS input, output and bypass terminals | Loose lugs, an overloaded phase |
| Battery string | A loose inter-cell link, a block with high internal resistance |
| UPS power modules and capacitors | Fans or cooling paths that have failed |
| PDUs and panel breakers | Overloaded circuits, loose terminations |
| Switchgear and transfer switches | Worn contacts, loose bus joints |
Each finding comes with the infrared and visible images, the temperature difference against its reference, the load at the time, and a priority. Re-scanning after the repair proves the fix.
Power quality survey
A recorder sits at the UPS input, or at a distribution point, for several days and logs voltage, current, frequency, harmonics, sags, swells and transients. It answers questions a single visit cannot:
- Why does the UPS go to battery or bypass when nothing else noticed?
- Does the generator hold voltage and frequency well enough for the UPS to accept it?
- Are harmonics from the load heating neutrals, cables or transformers?
- Is the load growing toward the UPS rating, and on which phase?
When to book it
- Once a year, in the same window as the UPS preventive maintenance visit
- After a fault, a breaker trip or a transfer nobody can explain
- Before and after adding significant load
- During a load bank test, when every connection carries full current
Common questions
How often should electrical equipment get infrared thermography?
NFPA 70B lists infrared thermography of all equipment every 12 months, and every 6 months for equipment in poor condition [1].
What does thermography find on a UPS?
Loose or corroded terminals, unbalanced phases, overloaded conductors and failing battery links, all of which run hotter than they should under load.
What is a power quality survey?
A multi-day recording of voltage, current, harmonics and disturbances at the UPS input or a distribution point, used to explain unexplained transfers, trips and overheating.
Does thermography require a shutdown?
No. It needs the equipment under load to show anything, so it is done with the site running.
Sources
- National Fire Protection Association, NFPA 70B (2023 edition) second revision committee report, Table 9.2.2 Maintenance Intervals
- National Fire Protection Association, Safely Maintain Electrical Equipment According to NFPA 70B, paragraph 1
- CSA Group, CSA Z463:24 Maintenance of electrical systems, Preface/Scope
Updated