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I find it interesting because often the best way to achieve a safe building code is to learn by allowing with basic guard rails and iterating as things happen. This isn’t ideal for the rare individual impacted by the “things happening,” but collectively we refine and iterate. Our current standards weren’t arrived at by navel gazing - we got the codes we have by experience. It’s hard to realize that from the present that you can’t reasonably learn without doing and by constraining without learning prevents growth and learning.

by jerlam39 minutes ago|

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"Things happen" is a interesting way to say "houses burn down and kill everyone inside". And I don't believe that electrical standards were developed with the idea that houses could both consume and generate electricity.

Not to mention that most houses aren't up to current electrical standards, much less fire codes.

by zdragnar3 hours ago|

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Are there lessons on safety that need to be learned here? We already know what the happy path looks like, and we've plenty of lessons on what the unhappy path will look like.

It isn't as if electric charge coming from balcony solar panels is some new magical-seeming type of electricity.

by foxglacier2 hours ago|

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Safety is statistical and depends on human behavior. Unexpected behaviors might appear. For example some places require a power outlet on kitchen islands because with out, people will use cords to the wall which creates tripping hazards.

Also, why do wires have to be fixed to joists every 300 mm? It's not about the electrons.

by labcomputer3 hours ago|

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“Unidirectional breakers” aren’t a thing for AC circuits.

by aaronmdjones16 minutes ago|

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Yes they are. Current alternates direction, but power usually only flows in one direction, from the input terminal (from the bus bar) to the output terminal (that the circuit is wired into).

If the circuit will be supplying power too (e.g. battery storage, an EV and EVSE that supports powering the house from the EV, etc) then you need a bidirectional RCBO.

People with no differential fault protection need not worry about any of this, they'll just be killed when it goes badly wrong.

Source: Am a UK electrician

Example: https://assets.cef.co.uk/downloads/pdg/wylex_nhxs1b32_datash...

EDIT: To say nothing of people with unidirectional electricity meters; plugging these into those setups will get them prosecuted for electricity theft. All SMETS 2 smart meters are bidirectional; you'd best check your meter if it isn't one of those.

by jonatron3 hours ago|

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https://www.bgelectrical.uk/uk/circuit-protection/devices/rc... Right there, both bidirectional and unidirectional breakers.

by formerly_proven1 hours ago|

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It would be really interesting to know what's so special about these UK units that they can be "damaged" by being fed from the "wrong" side (as per some other article), considering that the only place where these behave like that is an island north of France.

by hamdingers1 hours ago|

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Not in the US, but in parts of Europe they effectively use AFCI/GFCI breakers for everything.

by bluGill40 minutes ago|

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Those are code in the us now too. (with exceptions for where they don't make sense)

by formerly_proven4 hours ago|

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The situation in germany is essentially the same, but that's why net supply by these is limited to 800 W. I don't think anything changes w.r.t. earth leakage, why would the presence of the solar supply change anything from the RCD and fault point of views, respectively?

by mytailorisrich4 hours ago|

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Not expert but one difference is that in Germany the standard wiring is radial circuits with 16A MCBs while in the UK it's ring wiring with 32A MCBs.

So in the UK we have 2.5mm^2 wires in a ring on a 32A MCBs... Of course a 2.5mm^2 wire is rated ~20A so any issues with the ring (sockets still work since connected from the other branch) can burn the wire before the MCB trips...

by formerly_proven4 hours ago|

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The "standard" wiring is 1.5mm² on 16A MCBs which are rated to trip at 1.13-1.45x nominal current (so 18-23 A). So this is already mildly improper because you can pull elevated currents continuously and dramatically shorten the life of the insulation.

by 5 hours ago|

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