Believe what you want UKPN, the response I’ve seen from the DNO is pathetic (I’ve only just taken up the case), and I have done the measurements, calculations and submitted a detailed report, and await the outcome. Have worked for the CEGB -power stations- that was a while ago!), and most recently, as a Council Electrical Contracts Engineer (a hobby during retirement), and even surveyed total plant and services for major NHS hospitals (some of them are in a mess!), and much more. Including as a drives engineer and controls specialist over a long career in the industry. I am very use to having to do such investigations, but not up to date with latest Reg’s (several years into retirement), hence the question on here, and appreciated the answers. Now sitting on it awaiting DNO response. Back in 2006, after initial early retirement, I also completed the C&G2391, not because I needed it, but because it looked interesting, and found in practice that some of it could be nearly as difficult as earlier degree and HNC’s exams, and back then, most failed it, but I think they have simplified it since.

Believe what you want UKPN, the response I’ve seen from the DNO is pathetic (I’ve only just taken up the case), and I have done the measurements, calculations and submitted a detailed report, and await the outcome. Have worked for the CEGB -power stations- that was a while ago!), and most recently, as a Council Electrical Contracts Engineer (a hobby during retirement), and even surveyed total plant and services for major NHS hospitals (some of them are in a mess!), and much more. Including as a drives engineer and controls specialist over a long career in the industry. I am very use to having to do such investigations, but not up to date with latest Reg’s (several years into retirement), hence the question on here, and appreciated the answers. Now sitting on it awaiting DNO response. Back in 2006, after initial early retirement, I also completed the C&G2391, not because I needed it, but because it looked interesting, and found in practice that some of it could be nearly as difficult as earlier degree and HNC’s exams, and back then, most failed it, but I think they have simplified it since.