A storage rack comprises horizontally extending front and back beams having upper surfaces, on which is supported a roller track comprising two side rails, a series of rollers journalled between and projecting above the side rails, and a series of tie rods extending between and bracing the side rails. An uplink transmission power for a transmission from a communication network element to a communication network control element is calculated. The stationary blade frame is movably provided with the main frame such that the stationary blade is moved to a release position where a press contact state between the stationary blade and the movable blade is released while retaining a position of a printing device.