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[Jenks_C]

Apologies if this is a bit long winded :oops: We own part of an old stable block which divied was up into individual units some years ago. Our part of the building was rewired sometime during the last 10 years and is supplied via an old (Earlam?) 8 way consumer unit. We have just acquired some additional rooms to one side of our party wall which was wired around the same time and has it’s own consumer unit and wiring for and electric shower and water heater. The 25mm feeds and earth have been cut and I need to connect it to my supply.

My question is, would it be ok to replace my existing fuse box with a split load fuse box and use one half of it to feed the CU in the newly acquired section or am I totally not understanding the point of split load CU’s?

I hope this makes sense and sorry for such a long question.

Cheers in advance

[ericmark]

This is not the function of a split consumer unit. They are designed to allow the use of a RCD to 415.1.1 (30ma) to supply one half of the board while the other halve is either just switched or has an RCD to 411.5.3 (Most likely 100ma).
You simply need a supply from a large MCB to the other consumer unit. I can’t recall the Earlam 8 way consumer unit and I wonder if MCB’s are available for it?
An electric shower and water heater are likely to need a big supply at least 45 amp so a 50 amp MCB would be likely size to use some older units will not have this option.
A stable will come under Agricultural and Horticultural premises and has special requirements including 300ma RCD’s for fire protection and may be controlled by the electricity at work act. As such it should be inspected and tested every 3 years the max for anything with the exception of domestic is 5 years. From June volt drop has to be measured as part of the inspection and test so cable sizes need to be calculated to ensure everything complies with nearly 400 pages of regulations to comply with you will need an electrician on site with the question you ask you quite obvious don’t have the knowledge for DIY and if under the HSE then they will close it down and take you to court if you do not comply. If you think you come under domestic then except for Scotland Part P has to be complied with so you will need someone qualified to do the work. So I would see what the man on site recommends.

[Jenks_C]

Thanks Eric, the building is completely converted to domestic use, not commercial in any way.

I did speak to an electrician some time ago and he suggested installing a second set of links from the meter. I then saw the split load CU's in B&Q and it started me wondering and if it had been permissable I thought that might have been and easier/cheeper option than fitting additional links seeing as I would like to replace the CU with a modern one with RCD's.