I want to know what do you think?

What was probable cause?

Before that, for last 2-ish years I must replaced 5 LED bulbs.
No other symptoms.

Right before failure, one or two LED bulbs started blinking. I heard “scorching” sound.
And smell of burned electric/electronic (isolation).

Then I disconnected all circuits and opened all surrounding boxes…
Over-current breakers or RCD/GFCI didn’t tripped.

Extra photos:

(ignore temporary jumper - fixed now)

  • lnxtx (xe/xem/xyr)@feddit.nlOPEnglish
    1·
    3 months ago

    Now the big question is, why didn’t the breaker trip on its own?

    Not enough angry pixies to trip a breaker I think.
    16 A, so at least 3.5 kW power needed → block with loose connection will burn, not melt.

    Summary

    Avoid Legrand brand at all cost:

    • block bus screws are shit, soft metal
    • 3 separated block bus, metal link(s) are not provided

    .

    About consumer unit:

    • “hot” phases: link cables used instead of bus bars
    • maybe second neutral cable should be used instead of wire link
    • no one checks wiring inside unit; only RCD/GFCI is checked

    .

    I had a small UPS on top of the unit - shit…