My house has the main breaker provided and installed by the electric company, that's regulated to 15A, and a panel that only has an old nonstandard 16A breaker.

I live in Portugal (I believe is same standards as EU). I am upgrading the electrical panel and I currently have a 40A/0,03A differential and a main 40A breaker, then for distribution after those I have one 32A, four 16A and one 10A breakers.

But I have seen a few schematics without the main breaker (in my case the 40A). Do I really need the 40A breaker on my installation considering that I have the company main breaker just before the panel?

Note that the set up is meant to handle upgrades to the contracted power to at least 28A.

  • You've seen schematics for primary panels without a disconnect? That's allowed in some cases for subpanels, but I don't think a main panel can be without a disconnect. What's your nominal voltage there?
    – isherwood
    May 25, 2023 at 12:57
  • 2
    Just a general comment that should be good world wide. Having a main disconnect/main breaker where it is easy to turn off is good. This should protect the panels, so having a main breaker in the panel becomes less needed/optional.
    – crip659
    May 25, 2023 at 12:58
  • The voltage is 230/240v, and yes is the primary panel, but with the company breaker right by its side, accessible, if that matters.
    – Barreto
    May 25, 2023 at 13:10
  • 2
    If the extra panels are close together(same room) then other main breakers not really needed. If the panels are far apart, then having a main breaker in them is handy, but not needed. You/electrician just have to walk a distance to work on the far panel.
    – crip659
    May 25, 2023 at 14:33
  • 2
    Really the best place to ask is at your local building/electrical permit office/department. Electrical codes are usually country wide with the local city/town/state/province having their own extra code(if not just the country code) to go by. Example is most of the U.S. can use electrical cable with conduit being an option, but certain states/cities allow only wires in conduit, no cables allowed/legal.
    – crip659
    May 25, 2023 at 17:26

1 Answer 1


It shouldn't need a main breaker per se i.e. for its role as a circuit breaker. However all breakers are at least one other thing:

  • a disconnect switch
  • an RCD or GFCI

Quite often you don't need a breaker, but you do need one of those other things. And when you try to actually procure that other thing, you find that economies of scale have screwed up the market, and made "breaker and your thing" to actually be cheaper than "just your thing by itself".

So, you go with the flow and accept an entirely redundant breaker simply to get the other thing.

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