UK What constitutes a new circuit?

[Jefferson steelflex]

Hi guys, any fellow electricians good with definitions know what exactly constitutes as a new circuit with references if possible.
I know changing an mcb requires an eic, but does that constitute as a new circuit?
Just want to specify it on my paperwork

 

[Pete999]

I think he meant, just changing an mcb, for whatever reason, with new cabling would constitute a new circuit

maybe.

 

[pc1966]

Not my area but...I assume the whole point of assessing a "new circuit" is to cover the key aspects:

• Design - assessment of requirements, resulting choice of cable, MCB/RCBO, any special area rules. Can you show these?
• Implementation - quality of work and attention to detail in CU, cable route, and accessory.
• Testing - evidence that it was adequately tested to verify design assumptions (R1+R2, Zs, etc) as well as any implementation or component faults (IR check, polarity, etc)

Even some trivial or manufactured project work that allows all to be demonstrated should be enough in my mind.