EICR Certification DNO Fuse

You cannot verify that anyway Andy. Measurements of PSCC are not accuraate on a MFT. Unless it is very low the error band is at least +- 25%, In any domestic you don't care anyway as the ultimate current limiter is the DNO fuse, and the whole CU rating thing is based on that fuse. If you did (very unlikely) measure 8kA, how can the problem be fixed, as generally CUs are not type tested or rated with 10kA breakers? You would therefore have to change to industrial encloseures, and life gets expensive for a consumer who probably does not need that rating anyway. Disconnection of a tails short, or busbar or similar is down to the DNO fuse. The normal 6kA breakers should cope with anything else, although they may be damaged. Once you have gone a few metres the problem has gone anyway. Perhaps this is a way to get an "up front" MCCB into all domestic instaallations...........

You cannot verify that anyway Andy. Measurements of PSCC are not accuraate on a MFT. Unless it is very low the error band is at least +- 25%, In any domestic you don't care anyway as the ultimate current limiter is the DNO fuse, and the whole CU rating thing is based on that fuse. If you did (very unlikely) measure 8kA, how can the problem be fixed, as generally CUs are not type tested or rated with 10kA breakers? You would therefore have to change to industrial encloseures, and life gets expensive for a consumer who probably does not need that rating anyway. Disconnection of a tails short, or busbar or similar is down to the DNO fuse. The normal 6kA breakers should cope with anything else, although they may be damaged. Once you have gone a few metres the problem has gone anyway. Perhaps this is a way to get an "up front" MCCB into all domestic instaallations...........