Max PFC gone through the roof....Ideas anyone?

[Bobster]

Megger LTW425 Loop Impedance Tester

£379 that's without forum discount.

 

[spark 68]

Most DNO's, if asked (by enquiry) would say 16kA is the max PFC available on a single phase 100A or less supply.

I don't for one minute believe the Op's supply is any where near the levels of PFC his meter's are indicating, due to inaccuracies and method of measurement, as many posters here have already pointed out.

Typically EFLI meters measure the volt drop in mV at a measurement of around 20-25A load, and at close to the TX is at the lower end of the instruments capabilities (check the accuracy figures quoted in the user manual).
Under actual kA fault levels it is doubtful the TX could even supply the installation at that level of fault current before the cut fuse failed

The OP would either need a more accurate meter, or use IQ's method of measurement, as any slight discrepancy in the loop reading has a massive bearing on the PFC reading.

When you consider the DNO's supply cable has some resistance, as well as the cut out fuse and the meter itself as well the tails, then the calculations don't really add up, as the fuse, the Dno's cable, the meter and the tails would need a total resistance of 0.001 ohms for a PFC of 23kA single phase calculated @ 230V