G1 Z0 should always put the nozzle on the bed. A print normally starts by moving to one layer height above the bed though.
If you home away from the bed it should home to Z MAX, so Z = 0 is still at the bed.
To go to Z MAX do G1 Z999 and the soft limit should stop it a ZMAX but that should always be where the nozzle is furthest away from the bed.
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