It is for those who write the legislation to make it as clear, or unclear, as they wish. As it has been written (in England), the only thing that is notifiable is "
replacement of a CU" - so, as I said, it is down to the individual to decide how to interpret that. In terms of everyday English, if I asked someone to "
replace" a switch, socket, extractor fan, immersion, sink, boiler, washing machine or whatever (or even a CU
), I would expect them to remove the existing one and install a new (or, at least, different) one, wouldn't you?
That might seem silly (albeit all the fault of the legislators!) but, when it comes to legal things it is "what the law actually says" that matters. However, that aside, the issue is nothing like as straightforward as some of you seem to be making out....
....RF seemed to think that merely disconnecting and then reconnecting circuits to a CU was enough to constitute a 'replacement', requiring it to be compliant with current regs and also notifiable. However, I disconnect and reconnect (all of the) circuits from my CU whenever I test my installation - but I wouldn't think that anyone would seriously suggest that such might require me to upgrade the CU to comply with current regs, let alone to 'notify' my testing!
....Both RF and yourself also seem to feel that 'extending the wiring' is also an issue. However, it is very clear that (in England), provided only that no 'new circuit' is created (and that it's not in the zones of a bathroom), extending
any circuit or cable is NOT notifiable - and there's nothing to say that that does not apply to extending circuits/cables at the CU end just as much as at the other end (or anywhere in between).
What is your feeling about replacement of devices (MCB, RCD, RCBO, Main Switch or even SPD!) - do you regard that as 'notifiable'? ... and then what if it were many or most (or even all) of the devices? Anticipating your probable answers, where exactly would you 'draw lines'? As I've said, little of this is 'black and white'.
Fair enough - but what if, perhaps as a matter of convenience, you had disconnected all of the cables before you relocated the CU and then reconnected them - would you then think this had turned the non-notifiable job into a notifiable one?
That takes me back to the first point I made enough. If you undertook tests as for an EICR, you presumably disconnected and then reconnected many/most/all of the circuits in order to undertake the testing - so, even if you hadn't disconnected/reconnected the circuits as part of the 'CU move', you would subsequently have done it, anyway!!
Kind Regards, John