- Reaction score
- 1,345
I am going to a job this afternoon, new shower circuit. I noticed yesterday that the Wylex CU has a 100mA S-type RCD as the main switch and all the circuits are on 30mA RCBOs. PME system as far as I could tell (certainly not TT). Didn't give it much thought then, but was thinking about it last night in bed (sad, I know). Initially I thought there is no problem with this arrangement, a bit unnecessary perhaps. But I was thinking, as the RCBOs are single pole, a sustained N-E fault on any of the circuits would trip the upfront RCD and take out the whole installation. Other than that, I can't see an issue with it, unless I'm missing something. Do you folks think this in itself is reason enough to recommend replacing it with a vanilla main switch, or would you just leave it in situ? And have I missed anything?