The IET is carrying out some important updates between 17-30 April and all of our websites will be view only. For more information, read this Announcement

This discussion is locked.
You cannot post a reply to this discussion. If you have a question start a new discussion

Can I add RCBOs to a dual RCD board under a TN-S system?

Hi I'm an not an electrician, but a Level 2 Electrical Installations student with not alot of electrical knowledge. A relative is getting her kitchen re-wired and two consumer unit changes will be required. I have two problems

There are two consumer units. The first one has 2 double pole 63A/30mA RCDs protecting 5 MCB's each with the smoke alarm on one of the MCBs. The second consumer unit is smaller with just one 80A/30mA RCCB protecting 4 MCBs

A different electrician from the one doing the job performed the EICR on his report and pointed out with a C3 code that the 'smoke detectors are not a separate rcbo'. and 'No surge protection has been provided'.

So, would we be able to add just a single RCBO for the smoke detector and put it into the dual RCD board or would changing the dual RCD CU to a 10 rcbos suffice? Also, do I have to buy surge protectors for both consumer units or just the larger one, cause the smaller CU is only protecting the kitchen lighting and ground/first floor lighting because I thought surge protectors would only apply for socket circuits.

Sorry for the long description, but this is an urgent matter and any help will be appreciated. Images of both large and small CU are below

Parents Reply Children