low and now high Ipf

[peehead]

Hi,

I recently did a testing and inspection on a 3 year old flat, 3rd floor. From the installation cert the Ipf was recorded at 1.7KA but when I tested yesterday with a metrel Mi3000 mft The highest reading to be recorded was 8.30KA.

Pfc was 8.30
Pscc was 4.90 KA
Transformer is across the road.

Just wondering if anyone could give a reason for a high reading now?

 

[Richard Burns]

It is odd that your PEFC is higher than your PSCC it is usually the other way around, or they will be the same if TNCS earthing.
I would check that you have tested correctly.

If the previous test were done before the DNO had made changes to the supply cable in the street then this could change the reading, similarly a lot of paperwork has made up numbers on it!

 

[peehead]

I did the tests a couple of times and pefc was always higher. I was thinking that due to other flats etc not being on the load maybe that might be something to do with it.

 

[IQ Electrical]

Hi,

I recently did a testing and inspection on a 3 year old flat, 3rd floor. From the installation cert the Ipf was recorded at 1.7KA but when I tested yesterday with a metrel Mi3000 mft The highest reading to be recorded was 8.30KA.

Pfc was 8.30
Pscc was 4.90 KA
Transformer is across the road.

Just wondering if anyone could give a reason for a high reading now?

Did you measure Ze at both visits?
What was the Ze value on the EIC?