RCD Protection Ask questions and find answers to many subjects relating to electrics and electrical work

[chris68]

Can anyone please advise ...

The electrician doing the work on my house extension says he can't wire to my existing fuse panel becasue it isn't RCD protected. Is this the case? My house is about 30 years old with a rewireable fuse links. The supply to the house has an earth wire provided by the utility.

I can see the safety benefit of having an RCD trip but I don't know if wiring regulations state that you must have one. (Note, my electrician wants £300 in addition to what I'm already paying to swop out the fuse panel).

Best regards,
Chris

[sparx]

Hi Chris,
If your earth is from cable sheath (TN-S) then no RCD required,
If from neutral block of 'cut-out' (TN-C-S) also called PME then circuits 'Likely to power appliances out doors' ie ground floor skts should be RCD protected, either whole circuit or designated RCD skts by doors etc.
To supply & fit & provide test sheets for board change £300.00 is cheap, bearing in mind he also has to pay to notify L.A.blg. Control via his part p registration organisation, which takes on-line time and small fee also,
What about your earth bonding to incoming services, gas water etc? if you still have B.S. 3036 rewireable fuses chances are installation not up to standard, I don't think he is doing anything other than what is required by his reg. org. to make you aware of limitations of your installation, regards
SPARX

[stecook_elec]

Your Spark is right! If he has installaed new circuit to extension, then this circuit needs to have RCD protection as any new circuits installed that hand-held portable equipment can be used externally(lawn mower for example) has to have disconnection time of 0.4 seconds, which is what a 30mA RCD provides....Hope this helps!!!!!!!!!!!!!!

[stecook_elec]

Your Spark is right! If he has installaed new circuit to extension, then this circuit needs to have RCD protection as any new circuits installed that hand-held portable equipment can be used externally(lawn mower for example) has to have disconnection time of 0.4 seconds, which is what a 30mA RCD provides....Hope this helps!!!!!!!!!!!!!!