Full rewire required?

[TinnyB]

This is why an EICR is a must, so that the current circuit arrangements can be established before working out what to do next.


By 'etc.' yes I meant all other relevant tests.

Will an EICR actually establish the circuit arrangement - in the sense of establishing the configuration of the wiring? Presumably if it does it will provide a schematic wiring diagram (of, in this case, the connection of each socket, fan etc to the consumer unit)? I have seen a couple of EICR certificates and I am pretty sure than none of them included, or had appended, wiring schematics.

 

[brianmoooore]

An EICR which has been done thoroughly will need to establish the circuit arrangements in order to check that nothing contravenes the regs.
As an example, you would need to confirm not only that a RFC is complete, but that any spurs are single spurs, and not a spur fed from a spur.
This won't produce any schematics as such, but it would be a fairly small extra step to do so.

 

[DefyG]

Schematic? No not normally. It will for example, provide the number of sockets on each circuit and what areas covered for compliance with BS7671 so shouldn't be too difficult to draw your own schematic from the EICR.
'Circuit Arrangements/Configuration' as far as BS7671 goes will include circuit type, cable type/size, protective device type/rating, floor area (in the case of radial circuits for 13a outlets) etc.

 

[TinnyB]

An EICR which has been done thoroughly will need to establish the circuit arrangements in order to check that nothing contravenes the regs.
As an example, you would need to confirm not only that a RFC is complete, but that any spurs are single spurs, and not a spur fed from a spur.
This won't produce any schematics as such, but it would be a fairly small extra step to do so.

From the table in my original posting you will see that there are 11 sockets which are spurs and feed spurs - these are sockets listed under AA) and DD). With the current MCB this does contravene the regs... hence the tentative proposal in my original posting. So would the EICR establish the wiring configuration or simply establish the non compliances of the existing system? It seems to me that it is quite a big step to produce the schematics in question - not particularly difficult but time consuming (and perhaps unnecessary).

 

[brianmoooore]

Every socket which is part of a RFC can feed a spur*. It used to be quite common to find a RFC feeding upstairs sockets only, with spurs being taken from them to each feed a socket in the room below.
What cannot be done is to have an unfused spur in 2.5mm2 from a RFC, which then loops on to another socket.

* Wouldn't be considered good practice now, but still within regs.

 

[DefyG]

So would the EICR establish the wiring configuration or simply establish the non compliances of the existing system?

It would establish what was compliant or non-compliant about any given circuit. Non-compliances are coded. No code = compliant circuit.

not particularly difficult but time consuming (and perhaps unnecessary).

Yes which not necessary part of EICR as customers do not want to pay the extra time.

 

[TinnyB]

Schematic? No not normally. It will for example, provide the number of sockets on each circuit and what areas covered for compliance with BS7671 so shouldn't be too difficult to draw your own schematic from the EICR.
'Circuit Arrangements/Configuration' as far as BS7671 goes will include circuit type, cable type/size, protective device type/rating, floor area (in the case of radial circuits for 13a outlets) etc.

How simple would it really be to draw the schematic? In this case there are 8 sockets (sockets BB) and CC)) - connected in the ring main. There are 18 sockets connected as spurs with 11 of these being 'intermediate' spur sockets (sockets AA0 and DD)) and 7 being 'end' spur sockets. I find it difficult to see how the actual configuration could be determined without testing specifically for this purpose

 

[TinnyB]

Every socket which is part of a RFC can feed a spur*. It used to be quite common to find a RFC feeding upstairs sockets only, with spurs being taken from them to each feed a socket in the room below.
What cannot be done is to have an unfused spur in 2.5mm2 from a RFC, which then loops on to another socket.

* Wouldn't be considered good practice now, but still within regs.

Are you sure that you cannot have an unfused spur which loops on to another socket? What if the consumer unit MCB is selected to protect the radial type connections. As far as I can determine this would be compliant - hence the tentative proposal floated in my original post. In post #8 pc1966 at least seems to concur.

 

[brianmoooore]

A radial circuit can have sockets looped from one to the next, but a conventional RFC, fused at 32A and made up entirely with 2.5mm2 cable can only have one socket (single or double) on the end of an unfused spur.

 

[TinnyB]

A radial circuit can have sockets looped from one to the next, but a conventional RFC, fused at 32A and made up entirely with 2.5mm2 cable can only have one socket (single or double) on the end of an unfused spur.

Quite so. No disagreement with this. Hence the final para of my original post. And for example post #18. I apologise if somehow I have suggested that what you say in post #19 was not the case. I did not mean to do so. I agree with what you say in post #19