Where MEN earthing is used: the MEN connection is made at the main switchboard, so alternator neutral-to-frame links in the set are removed where the set's switchboard is not the main switchboard; when a set is the primary or alternative source for an installation, its alternator winding must have no internal connection to the set's earthing system, leaving the main switchboard's MEN link as the sole neutral-earth connection; and where the normal supply is MEN, the incoming neutral must not be switched ahead of the MEN link.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.