On Mon, 05 Feb 2018 13:28:03 +0000, John Rumm wrote:

Wylex do single module RCBOs, so as long as there is enough height in
that CU (RCBOs are taller than MCBs) you should be fine.

Wylex and Crabtree (Same Group?) have announced new 2 pole standard
height RCBO's. There are rumours that this (2 pole switching) is going to
be a requirement in the 18th edition, though there was no mention of it
in the Draft for Public Comment when it came out.
The Wylex press release also says something like 'adheres to new 18th
edition standards.'

https://electrium.co.uk/news/crabtre...with-switched-
neutral-as-standard

https://www.voltimum.co.uk/civicrm/mailing/view?
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