To overcome this "oversight" they are proposing to install a local autotransformer of vector group Zn0 to generate a neutral for the load. The "new" neutral will not be earthed at this point however the source where the 3-phase eminates from is a 415v transformer with solidly earthed star point.
they are proposing this to save running a new cable (excavation required). I've never seen this before and have a few questions.
Has anyone had experience of this type of "fix"
The installation is difficult to explain but I can issue a simple diagram if required.