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In some buildings, I've noticed circuit breakers in what appear to be ordinary electrical boxes. For example, in some musical practice rooms, the light, fan, and a receptacle are all switched by a breaker which is mounted in a way similar to a light switch, except for a placard explaining how to reset the breaker if it trips. I would expect things were done this way so that someone who accidentally overloads the breaker would be able to reset it without having to find a custodian with a key to the main electrical box.

While I doubt that I'm going to rewire my kitchen any time soon, it is sometimes a nuisance having to go to the basement to reset a kitchen breaker if two high-draw appliances get used simultaneously on the wrong receptacles. It would seem nicer as a design to have a master 40A feed to the kitchen and then have a 20A breaker near each receptacle so that any combination of receptacles could be used to draw up to 40A total, rather than to have to worry about which receptacles could be used together and then have to visit the basement in case of a mistake. Would such a design satisfy code requirements (I would think having enough outlets total, driven through enough 20A breakers, and fed with at least 40A of capacity, should qualify)? Would there be any problems with such a design?

Alternatively, are there any outlet assemblies with built-in breakers that would be approved for permanent installation (unlike e.g. power strips), and which could be safely fed from a greater-than-20A circuit?

  • What part of the world is this in? – Tyson Jul 14 '18 at 14:18
  • Is there any labeling on these sorts of boxes you can find? – ThreePhaseEel Jul 14 '18 at 14:26
  • It's been a few years since I've seen one. I think they were labeled with a manufacturer name (though I've completely forgotten what that would have been) and the aforementioned placard. When I first saw one of those assemblies, I was confused by the purpose of the reset instructions since I didn't realize it was a circuit breaker--it just seemed like a switch with a stubby handle. I remember where I first saw such things about 40 years ago, and have seen them occasionally since though I don't recall the specifics. – supercat Jul 14 '18 at 14:35
  • As Tyson asked it may help to know where in the world do you live and a photo of the box may also help. – Ed Beal Jul 14 '18 at 14:53
  • @EdBeal: USA. The ones I saw 40 years ago were in a Wisconsin elementary school that was built in the 1960s or 1970s. I don't have a photo, nor do I remember the particular places I've seen these things since. – supercat Jul 14 '18 at 15:15
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What you may be seeing is a flush-mount version of a spa panel or enclosed breaker

From your description, I would reckon that what you are looking at is something akin to a "spa panel" disconnect or circuit breaker enclosure, only in a flush-mounted configuration (vs. the surface mounting typically attributed to spa panels and enclosed breakers). These are usually 2-4 space loadcenters, with 70A to 125A bussing; larger versions use a breaker with line and load lugs instead, bolted to the box, and are called enclosed circuit breakers.

  • That sounds like that might be it. – supercat Jul 14 '18 at 16:34
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Modern kitchen electrical design is to have at least two separate 20 A circuits so that the high draw appliances are never used simultaneously on the same circuit. Over-current tripping of a breaker due to intentional overloading is unacceptable.

What you are describing is unnecessary, would be more expensive, and could have unforeseen faults and deficiencies. In the UK a high current (30 A or 40 A at 240 V) "ring circuit" is allowed with spurs off the ring to receptacles. A plug-in appliance will have a fuse in its plug (2 A, 5 A, 7 A, . . . ) to limit current to what the appliance wiring can take. The ring and spur reportedly uses marginally less copper wire. https://en.wikipedia.org/wiki/Ring_circuit

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    Electrically, it would be essentially equivalent to having a sub-panel in the kitchen, with a 20A breaker for each receptacle. The difference would be that rather than having all the breakers in one panel, having them nearer the outlets might make things clearer. If a kitchen design was intended to have a microwave plugged into one particular location, I suppose using a separate home-run for the microwave's receptacle might be another way of fixing problems with trying to use a toaster or blender at the same time as a microwave. I was also inspired by the question about what to do with... – supercat Jul 14 '18 at 16:39
  • ...a 50A circuit that was left over after switching an electric stove to gas. Using the wiring with a 20A breaker feeding normal outlets would work, but wiring sized for 50A should be able to feed more than one 20A circuit, if protection devices were installed between the 50A circuit and individual outlets. – supercat Jul 14 '18 at 16:40

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