Why preventive maintenance pays
Electrical equipment rarely fails without warning. Connections loosen and heat up, dust builds up inside switchgear, breakers stiffen after years without operating, and moisture finds its way into outdoor gear after an Edmonton freeze-thaw cycle. A preventive maintenance (PM) program finds those problems on your schedule instead of the equipment's.
The payoff is fewer unplanned outages, safer equipment and better information when you budget for replacements. Insurers increasingly ask for maintenance records, and CSA Z463, the Canadian guideline on maintenance of electrical systems, gives you a recognized framework to build on.
Start with an inventory
You cannot maintain what you have not listed. Walk the building with an electrician and record each major piece of equipment.
| Equipment | What to record |
|---|---|
| Switchgear and switchboards | Make, model, age, rating, last service date |
| Transformers | Size, type (dry or liquid filled), location, ventilation |
| Panelboards | Location, what feeds it, whether the schedule is accurate |
| Motor control centres and drives | Loads served, spare parts on hand |
| Generators and transfer switches | Run hours, test history |
| Emergency lighting and exit signs | Test dates, battery age |
Then rank each item by criticality: what happens to the building or the business if it fails? A main breaker feeding the whole building ranks higher than a panel serving a storage room. Combine criticality with condition and you know where to spend first.
Choose the tasks and the intervals
Typical PM tasks for a commercial or industrial building include:
- Visual inspection for heat damage, corrosion, water, dust and missing covers
- Infrared thermography under normal load
- Cleaning and torquing connections during a planned outage
- Exercising breakers and, for larger breakers, trip testing
- Insulation resistance testing on feeders, motors and transformers
- Ground fault and protective relay testing where installed
- Generator load testing and transfer switch operation
- Emergency lighting and exit sign tests
Our guide to infrared thermography explains what a scan finds and how to use the report.
Intervals depend on the equipment, its condition and how hard it works. A clean, lightly loaded office panel can go longer between visits than a switchboard in a dusty shop or a humid wash bay. Manufacturer guidance and CSA Z463 are good starting points. Then adjust based on what each inspection finds, and follow any testing frequencies required by the fire code or your insurer for life safety equipment.
Many PM tasks mean opening equipment that is or could be energized. That work needs a qualified electrician, a hazard assessment and the right PPE under CSA Z462. Facility staff should never remove covers to have a look.
Group the outage work
Cleaning, torquing and testing inside switchgear requires an outage. Many buildings bundle that work into a planned shutdown every few years, usually overnight or over a long weekend. Grouping tasks keeps the disruption to one event and makes the most of the electrician's time on site. Our guide to planning an electrical shutdown walks through the process.
Use each outage well. Before the shutdown, review the last scan, the deficiency list and any equipment that has been tripping or making noise, so the crew arrives with the right parts and a clear task list. After it, update the inventory with what was done and what was found. This is also a good time to fit infrared windows or replace obsolete breakers that are hard to source.
Keep records you will actually use
A PM program is only as good as its records. Each visit should leave a report with findings, photos, thermal images, test values and recommendations ranked by urgency.
After a few years, trends appear: an insulation reading slowly dropping, a connection that keeps warming up, a breaker that needed adjustment twice. Trends turn surprise failures into planned capital work. Alberta Electrical offers online job management and reporting, so reports, photos and deficiency lists stay in one place. Keep current single-line diagrams and panel schedules with them.
Getting started without a big budget
- Book an infrared scan of the main switchgear and the busiest panels.
- Fix anything urgent the scan finds.
- Build the equipment inventory and criticality ranking.
- Set a simple annual calendar for tests and inspections.
- Plan one shutdown for the items that need an outage.
Start small and expand. A modest program run consistently beats an ambitious one that stalls after the first year. See commercial maintenance and industrial maintenance for how we can help.
Common questions
How often should electrical equipment be maintained?
It depends on the equipment type, its condition and its environment. CSA Z463 and manufacturer guidance give starting intervals, which you then adjust based on findings. Critical or heavily loaded equipment usually gets attention more often.
Is an infrared scan enough on its own?
No. A scan is an excellent screening tool, but it does not check breaker operation, insulation condition or dirt buildup. It works best as one part of a broader program.
Do we have to shut the building down for maintenance?
Not for everything. Visual inspections and thermography are done with equipment running. Cleaning, torquing and most testing inside switchgear need an outage, which can be planned for nights or long weekends.
What records should we keep?
An equipment list, each visit's report, test results, thermal images, updated panel schedules and single-line diagrams. Keep them somewhere the next facility manager can find them.
Codes and permit rules change and every building is different. For work on your system, talk to a licensed electrician and your local permit authority.