Where to look
Open the door of the panel. The main breaker is the biggest one, usually alone at the top or at the bottom of the column.
A number is stamped on its handle: 60, 100, 125 or 200. That is the rating of your service.
What it changes
A 60 amp service is not enough today for almost any addition, and several insurers refuse it.
A 100 amp service still suits a lot of homes, as long as no large continuous load is added to it. An EV charger is one of those.
A 200 amp service leaves room for a charger, a hot tub, radiant floor heating or a heat pump.
Free slots do not mean capacity
This is the most frequent confusion. A panel can have six empty slots and no capacity available.
What counts is the sum of the loads already connected, calculated with the method set out in the Code. Free slots say nothing about that.
Master electrician, RBQ licence 5855-0849-01 and CMEQ member 17468. About ten years in the trade across Montreal’s Southwest and the South Shore.
Who does the work
