Abstract: An impedance controller is used for controlling electrode-to-bath spacing in an arc furnace. Measured quantities proportional to the electrode voltage and the electrode current are determined and an actual impedance value is formed from the measured values by means of a divider. The actual impedance value is compared with a predeterminable desired impedance value to derive a control signal. If in the event of a short circuit, the actual impedance value reaches a predetermined lower limit, a switching element sets into the controller a signal causing full drive, so that the electrodes are raised at maximum velocity. If the sum of the two measurement quantities becomes zero, the output of the controller is cut off.

Abstract: Objects to be stacked on a pallet or packaged without using a pallet, are transported by a conveyor to an inlet roll track where the objects are assembled into rows, from the inlet roll track a row of the objects is transferred to an intermediate support member where a layer of rows of the objects are collected and then picked up by a forklift device for movement to a pallet or a stack support. The inlet roll track is made up of a number of rollers which can be driven at variable speeds with the rollers most remote from the inlet to the inlet roll track moving at the lowest speed. Alternatively, the rollers of the inlet roll track can be arranged in groups with each group operating at a different speed and capable of being switched on and off separate from the other groups. The stack support can be moved vertically so that the forklift device places each layer on it in about the same horizontal plane as the stack is built up.