In response to Handyosprey, you are really looking for deterioration in the kind of install you are describing. So it is inspection not the measurment which is most important. Loose, corroded or damaged connections are your key, not some magic number which you may not be able to measure. As I said above, it may have been designed incorrectly and the disconnection is not exactly 5 seconds, it probably doesn't matter. What does is the burnt loose connection which you will not measure at all! FI or a C2 is not indicated because you have not found anything wrong, you have tried to measure in place of inspect. You have measured close to the correct number, that is the best you can do. You don't really know how accurate the number is, and finding out with another half a days work and 10 grands worth of kit, is not the way to go. If you tried that on a major installation you would never finish, and your EICR full of FIs is worthless. The original designer is still responsible for the design (errors or not), it is a bit like an MOT with brakes which do not exactly reproduce a new vehicle, a 5% error is not important, worn out pads or disks is. The EICR is to find the worn out or damaged items, not a certificate to replace the installation with new (although many treat it this way).

In response to Handyosprey, you are really looking for deterioration in the kind of install you are describing. So it is inspection not the measurment which is most important. Loose, corroded or damaged connections are your key, not some magic number which you may not be able to measure. As I said above, it may have been designed incorrectly and the disconnection is not exactly 5 seconds, it probably doesn't matter. What does is the burnt loose connection which you will not measure at all! FI or a C2 is not indicated because you have not found anything wrong, you have tried to measure in place of inspect. You have measured close to the correct number, that is the best you can do. You don't really know how accurate the number is, and finding out with another half a days work and 10 grands worth of kit, is not the way to go. If you tried that on a major installation you would never finish, and your EICR full of FIs is worthless. The original designer is still responsible for the design (errors or not), it is a bit like an MOT with brakes which do not exactly reproduce a new vehicle, a 5% error is not important, worn out pads or disks is. The EICR is to find the worn out or damaged items, not a certificate to replace the installation with new (although many treat it this way).