On Mon, 19 Aug 2013 14:45:15 +0100, Toby
wrote:
In my office, I had to change the 16A MCB for a type C, as that would
always trip on mains power restore if there was a power cut, which was
kind of annoying! - It had a 3KvA UPS' on it, plus some other small non
essential IT equipment we could live without during a power cut, so you
might want to look at replacing the RCBO with a type C to stop it
happening to yours too.

I'm pretty sure it's the RCD part of the RCBO that's tripping though,
so I don't think changing from a "B" to a "C" will make any difference
because that's just the MCB part.

Originally, I had six circuits (2 x B32 and 4 x B6) on one RCD, and
that RCD was occasionally tripping. I never had any MCBs trip. I
suspected the B32 circuit with the UPS/Servers on it, but wasn't sure,
so I swapped out both B32 MCBs for RCBOs, and now the B32 RCBO for the
UPS/servers circuit trips and nothing else.