After fixing a few CPC related issues on a ring final I got the following results
L-L = 0.47
N-N = 0.47
CPC-CPC = 0.69
R1+R2 Tested at 0.31
R1+Rn Tested at 0.25
All looks good, until that is I realised that the CPC-CPC is actually not quite right. It should be 0.78 (0.47 x 1.67 for a 2.5/1.5 T&E). But if that was plugged in (so to speak) the R1+R2 values are then wrong, but they are correct, so the readings at the board for the CPC are in fact right.
My assumption is that the cable used in the building is of a rather cheap variety and the conductors are actually 2.5/1.7. If you use that then the calculations match the readings.
I suppose you could argue the CPC readings are just outside tollerance (0.05 is the usual max, and this is 0.09), but I've not seen this before with my tester.
Anyone got any thoughts, or have you seen this type of thing yourselves. Is my assumption feasable that the conductors might not be exactly 2.5/1.5 ?
L-L = 0.47
N-N = 0.47
CPC-CPC = 0.69
R1+R2 Tested at 0.31
R1+Rn Tested at 0.25
All looks good, until that is I realised that the CPC-CPC is actually not quite right. It should be 0.78 (0.47 x 1.67 for a 2.5/1.5 T&E). But if that was plugged in (so to speak) the R1+R2 values are then wrong, but they are correct, so the readings at the board for the CPC are in fact right.
My assumption is that the cable used in the building is of a rather cheap variety and the conductors are actually 2.5/1.7. If you use that then the calculations match the readings.
I suppose you could argue the CPC readings are just outside tollerance (0.05 is the usual max, and this is 0.09), but I've not seen this before with my tester.
Anyone got any thoughts, or have you seen this type of thing yourselves. Is my assumption feasable that the conductors might not be exactly 2.5/1.5 ?
