Prospective fault current in a TT installation

[spud1]

Hi Chaps,

When measuring and recording PFC at the origin in a domestic 230V TT system for say an EI cert or an EICR, do you record the PFC L-N instead of L-E as this is clearly going to be highest reading if say Ze is 65 ohms?

 

[malcolmsanford]

You record the highest of the 2 readings, and 999,999 out of a 1,000,000 it will indeed be the PSCC you use on a TT system

 

[telectrix]

psccwill be higher than pefc. however because you measure the PFC with bonding connected, the difference will not be as high as you would calculate from Ze. due to parallel paths

 

[spud1]

Thought as much cheers guys!