Getting head around RCBOs and split CU's

[AndyPRK]

If your supply and consumer unit are in different locations, you can always fit the SPD near the incomming supply.

I download the wylex CU catalogue the other day. Wish I hadn't lol

https://www.electrium.co.uk/brands/wylex

Note alot of these could be special order.


Wylex used to sell both flexible and fixed bus bars.
Fixed for example meaning you had to have 5 on one side and 5 on the other RCD.
Where as flexible meaning you could have 6 on one side and 4 on the other for example. If this suited you house better.

And as John said, high integ ones meaning you could also have some separate MCB or RCBOs. In this case it would have 3 neutral connection blocks inside.

I expect you will go all RCBO, or RCBO and one RCD but I don't know what they stock these days.

There is also a brand called fusebox. A cheaper brand which electricians seam to respect. Their RCBO's are significantly cheaper if you wanted all RCBO

 

[SimonH2]

For that, the only thing that changed with the 18th edition is that people / manufacturers / other decided to actually read what 314 states and act upon it.

I think the big change has been in cost.
When RCDs first started being mainstream, they were expensive so a big incentive to only fit one for the circuits that needed RCD protection - and have some circuits non-protected. Then when the regs changed such that most things needed RCD protection, they were still not "cheap" so incentive to go dual-RCD rather than RCBO.
Now, depending on brand, RCBOs have come down significantly in price to the point where there isn't really an argument for having shared RCDs any more in most situations.
As always, the rule is "as far as is reasonable". When it comes to defining what is reasonable, you have to consider both cost and the customer's ability to pay for it. At one end, if the customer is struggling to decide between "heat and eat", trying to upsell them to the latest expensive option is more likely to result in them staying with the old Wylex rewire-able fuses they already have. On the other hand, if the customer is in a position to pay for it, upselling them to all RCBO makes sense. Obviously, as time moves on, the cost of the "expensive option" is coming down - so the decision point for "reasonable" changes.