R D S wrote:
So, as I suspected then the landlord has employed some ****wit at the
cheapest price he can find to upgrade the electrics.
Then when the electrician is scratching his head because the mcb is
tripping every time I switch a machine on ...

Being non-domestic premises, it's not required to be MCB/RCD
protected, insist on going back to a rewirable fuse consumer unit,
though a quick skim of the faq and wiki don't give me an
appropriate reference.

JGH