Hi All,
I know the above was done last year, but just a little bit knowledge
On some of the comments above, a registered installation electrician as well as a master installation electrician can sign of COC's on a solar installation. Both are allowed to work on DC circuits.
A registered single phase installation electrician may not work on 3 phase, as well as not allowed to work on DC circuits, therefore they may not work on solar as there is the DC component.
Difference between Master and Installation electrician is the master may work on electrical equipment in hazardous areas, e.g. flammable gases or dust may be present as this requires specialised electrical equipment (flameproof or explosion proof) and an installation (or 3 phase) electrician may not.
Hope this helps to clarify some points.