Abstract: A conveyor system comprises a series of mobile conveyors arranged end-to-end, each mobile conveyor including an inclined belt, the material being conveyed being lifted by the belt of each conveyor in turn and discharged over the upper end of the belt onto the lower end of the belt of the next conveyor. The belts are driven by electric motors. A downstream conveyor of the series constitutes a master conveyor which is connected to a source of electrical power. Each upstream conveyor in the series is a slave conveyor, the first slave conveyor receiving power from the master conveyor and each subsequent slave conveyor receiving power from the slave conveyor(s) upstream thereof. The slave conveyors receive power at timed intervals so that the conveyor system starts in sequence from the downstream master conveyor. Safety means are provided for switching-off all the conveyors that are upstream of the conveyor that is disabled in an emergency.