ARWadsworth wrote:

I was working on a Siemens Stratum today and I was going to spend tonight
looking for a second hand Siemens RCBO on the internet.

Glad to know the info was useful.

In my case the need to add extra RCBO's was because of a major kitchen
refit. In view of the part P implications I had the wiring done by an
appropriately registered sparkie. He was working on a new CU installation
nearby before starting our job so called round with a handful of different
breakers to try for size in a spare slot. I don't remember what the other
ones were but the Hager one fit OK. I'd assume Hager MCB's should fit too.

The main switch was also in a bad state with part of the casing broken off.
It had been like that since we moved in but was functional and (reasonably)
safe bur scary looking so we had that replaced as well. When he was
initially checking things for size he had a Hager and a Wylex one with him,
they both looked like they would be possibles when slotted onto a couple of
adjacent spare ways to check for size. When he came to do the job it was a
Wylex main switch that was in the van so that's what we now have. I'd
expect Wylex MCB's to have a similar profile to this so they would probably
also be compatible with this CU but I'm not sure about their RCBO's - I
can't remember if he tried one for size on the first visit.

Incidentally the Siemens Stratum is identical to one of the old MK CUs
(for which you also struggle to get parts).

Perhaps the Wiki needs updating to highlight the incompatibility between the
two different flavours of MK?

--
Mike Clarke