A method for concurrently programming a series of in-system devices by grouping the devices into sequentially-programmed groups, wherein a best possible grouping of devices is determined that achieves a minimum total configuration time. The invention teaches that the battery in the industrial truck can be changed easily and economically by providing an external roller conveyor that can be moved in the vertical direction. A stop is latchable in an inward position to allow reduction in the piston stroke by engaging an outward flange on the piston before the piston has moved fully downward.