Abstract: An arrangement for printing machine plate cylinder adjustment to zero position includes an evaluation circuit which is interposed between a potentiometer which issues an electrical signal representative of the instantaneous position of an adjustment transmission driven by a motor, and motor protection devices for the two senses of rotation of the motor. The evaluation circuit is operative for generating respective control signals for a right-hand end position, for a left-hand end position, for a right-hand switching point, and for a left-hand switching point.