Preventa XUSL_XUSL4E cascaded safety light curtain : is it possible to use the master segment alone?

In a cascaded light curtain version, the master segment monitors that the slave segment(s) is(are) not disconnected from the master segment (fault detection). By this way, it is technically not possible to use the master segment alone. At least the segment segment S1 without secondary connector, needs to be associated to the master segment XUSL4E**NM. This is the minimum hardware configuration. All the cascaded safety light curtains of the market, have the same behaviour.