fused spur to garage and outdoor socket

[pc1966]

Would changing the socket inside to a double socket with an RCD like this do the same job?

No, those RCD sockets only protect the thing plugged in to them.

You would need to plug the cable feeding all of the outdoor stuff in using a 13A plug to it (not such a bad idea, but not as convenient as it wired in properly).

I don't think the CU has an RCD in it, and they certainly haven't put an RCD in where they put the FCU.

Can you post some pictures of it so we can take a look?
[automerge]1589030620[/automerge]
Toolstation also do RCD FCU such as this:

RCD Spur White

• PowerBreaker RCD Fused Connection Unit• Passive (does not need resetting after a power loss)• High intensity LED power-on indicator• Fuse holder can be locked out for safety• Twin earth terminals• Conforms to BS1363-4:1995 Amd 1,2,3 and BS7288:1990 Amd 1• Cuts the power for added protection...

www.toolstation.com

If you don't have RCD already it really is a must, even though they are not really intended for protecting "fixed wiring" as such.

 

[Pinners27]

Should be self-explanatory. I’ve removed what was the FCU and now the garage is disconnected. The double gang socket is on the the circuit that’s on the second breaker in on the left hand side labelled ‘socket kitchen part 20A’

to be honest, I don’t even need a socket there in the kitchen anymore. I could just replace the double gang socket with an rcd.

 

[pc1966]

It looks as if all of the left breakers are on the RCCB (another name for an RCD) so you would not need a separate RCD FCU, a normal FCU would do. The picture is very small so it is hard to be sure of what the right had set of MCB are on, there appears to be a 2nd RCCB but what exactly it feeds remains to be seen.

You really should test-trip them regularly though!

But before you do, shut down any PCs and switch off things like TiVo boxes, TVs, fridges, etc, that might be unhappy at the supply going off and back on in a second or so.

 

[Pinners27]

Ok, great. Thank you again for all your help!

 

[pc1966]

One final bit of advice - do you have a socket tester?

Many DIY folks lack any test equipment. While they have many limitations, the ~£10 socket testers will warn of many of the most serious wiring faults (e.g. L & N swapped). Main limitation is they only detect a complete loss of earth, not a high resistance.

You also get ones in the ~£50 that do an earth impedance test which is better, and some also have an RCD test feature (one way to find out if the circuit is protected!) so might be worth considering. For example:

https://www.NoLinkingToThis/p/kewtech-loopcheck-107-advanced-plug-in-socket-tester/4670j

Not just for this new arrangement, if you get one you should go around all sockets in your home just to verify they are all good. Not a match for a sparky's MFT for sure, but they are in the £500-1000 range!