Each incoming supply from a set into the installation must be protected by its own overcurrent device inside the installation, operating in all active conductors with a setting not exceeding the lower of the supply cable rating and the inlet fitting rating; the generator's own overcurrent device does not satisfy this (A1 relocated this from 4.3.2.3).
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.