odd voltages detected on lighting circuit

As the LN voltage is OK, and the CPC is wobbling about between L-N, my money would be on a poor connection in the path between the MET and the point at the fitting you are measuring as the earth .

The exact voltages will be determined  by the  balance of things connected acting as a  voltage divider with two capacitors one LE and one NE - that could be a mix of the natural cacitaance of the wire and or the filter capacitors of any LED drivers that are connected.

Another clue would be that if you connected a moderate load or even a small capacitor accross that 115V it will probably collapse away to a low value.

The 'make or break' test of that theory will be a wander lead R2 test to the same point.

let us know what you find.

regards

Mike.

thanks Mike.

your expectation proved, Mike.  Thank you for your input.

When I picked through this (attached( lurking in the loft under the insulation and sorted it ... all was well.

Ah yes, the use of the fabric of the building as the enclosure.There must be loads like that dotted about. Nicely found... I presume there is now a wagobox or something.. Still apart from that no signs of fire or mice or anything so that's a plus. 

stirs memories of a similar quality set up where I unknowingly stepped on a ceramic screwit and broke so the wire end goes into the sole of the footwear and the foot..
Mike.

"...I presume there is now a wagobox or something..."  -  no one [on here at least] walks away from something like that without properly sorting it I hope   :-)  Thanks again.

"...I presume there is now a wagobox or something..."  -  no one [on here at least] walks away from something like that without properly sorting it I hope   :-)  Thanks again.