Using a multimeter set to AC isn't going to give you an ohmic value
The impedance between neutral and earth varies depending on the supply type etc, just as does the likelyhood of an RCD tripping on a N-E short regardless of loading on your installation.
The impedance between neutral and earth varies depending on the supply type etc, just as does the likelyhood of an RCD tripping on a N-E short regardless of loading on your installation.