Agree with the previous answer on earthing, but don't understand the need for 1 more rcd. Who advised and for what purpose, are you selling? If you already have an RCD then there should be no reason for a second. The installation you have, should have met regulations at that time and are acceptable now, providing you haven't altered, added or rewired since. That said, I have changed my consumer unit for a split unit because it is safer.
bob12241
April 2009
earth conductors have to half size upto 16mm2 then the y have to be the same size. i:e 2.5 cable will have a 1.5 earth 4 mm cable will have a 2.5 earth.mains 16mm will have a 10 mm earth and 25mm mains have a 25 mm earth.as for your rcd prob you can buy an entire split load dis board for around £75 including mcbs required for the installation.and you can ask for a test cert on completion.you are looking at around £450 for the test and dis board install and whatever extra for the work to bring the earthing up to scratch.
paul
February 2009
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