On 20/03/2019 18:11, Scott wrote:
I discovered a problem with a join in a ring main and decided to
replace the faulty connector with a terminal block. I wondered if
this needs to be rated at 30A to correspond with the fuse (RCBO) or if
15A would be okay on the basis that it is a ring and some of the
current will go each way round.

On the Brunel principle I am fitting 30A but I am curious to know.

If it all fits, I'd use the 30A based on the fuse size. The fuse is
there to protect wiring, and 15A seems a bit weedy just in case the ring
gets accidentally broken.