In article ,
"Christian McArdle" writes:
Is the answer don't even try. Or usually OK. Or always OK.

They usually fit (but not always, and sometimes with cosmetic issues).
However, they often come with dire warnings not to mix manufacturers'
products as it invalidates the type approval. This alone might cause the
panel to fail inspection.

This is something the US is very hot on* (UL type approval applies
to a combination of breaker and enclosure, and is voided by using
an enclosure the manufacturer didn't include for certification),
but providing the accessories fit properly, I've never seen this
regarded as an issue here.

* If you look in a US panel, you'll be horrified, and relieved it
wouldn't come close to getting approval in the EU.

--
Andrew Gabriel