What your panel actually does
Your electrical panel is where the power from the utility gets split into the individual circuits that run your lights, receptacles and appliances. Each circuit has its own breaker (or fuse, in older homes) that shuts it off if something goes wrong.
Most Edmonton homes have the panel in the basement, often near the furnace or on the wall where the service cable comes in from the meter. In garages and newer infills it may be on a main-floor wall or in a utility closet.
You do not need to understand the wiring to get useful information from the panel. Everything in this guide can be read with the door open and the inner cover left firmly in place.
Find the main breaker and your service size
The main breaker is usually the large breaker at the top of the panel, often separate from the two columns below. Switching it off turns off every circuit in the panel. Its handle is stamped with a number such as 60, 100, 125 or 200. That number is the main breaker rating, and in most homes it matches the size of your electrical service.
If you cannot find a main breaker in the panel, the main disconnect may be in a separate box beside it or near the meter. Some older homes have a fused main switch instead.
Many 1950s to 1970s Edmonton homes started out with 60 A or 100 A services. That was plenty for the time, but not always for a home with central air, a hot tub or an EV charger. Our guide on 100 A vs 200 A service explains what the number means for you.
The metal cover behind the door (the dead-front) is what keeps your hands away from live parts. The bus bars and the wires coming in from the meter stay energized even with the main breaker off. Removing that cover is a job for a licensed electrician.
Single-pole and double-pole breakers
Most breakers in a home are single-pole: one narrow breaker taking one space, feeding a 120 V circuit for lights and receptacles. Larger appliances need 240 V, which uses a double-pole breaker that takes two spaces with a single handle (or two handles tied together).
The number on each handle is the breaker's rating in amps. The table below shows typical pairings in a house, but the right size always depends on the wire and the equipment, so treat it as a guide to what you are looking at, not a rule.
| You might see | Typical use | Notes |
|---|---|---|
| 15 A single-pole | Bedroom, living room and general lighting circuits | The most common breaker in a house |
| 20 A single-pole | Kitchen counter, bathroom or some appliance circuits | Requirements depend on the room and the code edition |
| 30 A double-pole | Clothes dryer, electric water heater | Takes two spaces |
| 40 or 50 A double-pole | Electric range, EV charger, hot tub | Size set by the appliance and the wire |
| Breaker with a test button | GFCI or AFCI protected circuit | See GFCI and AFCI protection |
Read the directory and the circuit numbers
Breaker spaces are numbered, usually odd numbers down the left and even down the right. The directory on the inside of the door should tell you what each number feeds. In many homes the directory is faded, written in pencil decades ago, or simply wrong after a renovation.
A good directory names rooms and specific loads ("Kitchen counter left of sink" rather than "Kitchen"). If yours is vague, our guide to labelling your panel shows how to map it safely with a helper and a lamp.
- Count any empty slots or knockouts: these are spare spaces for future circuits.
- Look for breakers marked SPARE that are switched off and not connected.
- Note whether there are thin "tandem" breakers that fit two circuits into one space. A panel full of them may be running out of room, covered in when your panel is full.
What you can check, and where to stop
With the door open you can safely look for these warning signs. If you see any of them, call a licensed electrician rather than investigating further.
- A breaker or the cover that feels warm to the touch, or a smell of hot plastic.
- Buzzing, crackling or sizzling sounds from the panel.
- Scorch marks, melted plastic or discoloured breakers.
- Rust or water stains on or above the panel, common near old window wells or a leaky hose bib.
- A breaker that trips again immediately after you reset it.
- A panel brand or fuse box that your insurer has asked about. See obsolete and problem panels.
What to tell your electrician
When you book a visit, a few details save time on site and help your electrician bring the right parts:
- Take a clear photo of the whole panel with the door open, and one of the label inside the door showing the brand and model.
- Note the number on the main breaker.
- Count the spare spaces.
- Describe what you are planning: a basement suite, heat pump, hot tub or EV charger.
- Mention any tripping, warmth or noises, and when they happen.
Alberta Electrical offers home electrical inspections that include a full look behind the cover, a tightness and heat check, and a written summary you can keep on file or share with your insurer.
Common questions
Is it safe to open my panel door?
Yes. Opening the outer door to read labels or reset a breaker is normal. Do not remove the inner metal cover, which protects you from live parts.
My main breaker says 100 but my house is big. Is that a problem?
Not necessarily. Whether 100 A is enough depends on your actual loads, such as electric heat, air conditioning or an EV charger. A load calculation by an electrician gives the real answer.
Why are some breakers wider than others?
Wide breakers taking two spaces are double-pole breakers for 240 V appliances like ranges and dryers. Breakers with a test button are GFCI or AFCI types that add shock or arc-fault protection.
Can I add a breaker to a spare space myself?
No. Adding a circuit involves working inside the panel and needs a permit in Alberta. A licensed electrician can do it and arrange the permit and inspection.
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.