That doesn't really mean anything does it? Lots of things are possible.It is possible to supply the single-phase loads through a three-phase RCD. This would simplify
the arrangement a good deal, however it is not recommended to supply a mixture of single and
three-phase loads through one RCD. The reasons for this are beyond the scope of Phase 2 of the
apprenticeship.
Perhaps when they achieve Phase 3 of the apprenticeship it will be allowed.