DEVICE FOR DETERMINING THE ROTATIONAL SPEED OF A ROTATING MACHINE PART

摘要

The invention relates to a device (1) for determining the rotational speed of a rotating machine part (5), which comprises at least one signal input (13) to which the output signal (11) of a rotational speed sensor (10) can be supplied, an arithmetic unit (20) which can be used to calculated, on the basis of the output signal (11) of the rotational speed sensor (10), at least the rotational speed of the rotating machine part (5), and at least two signal outputs (25) for outputting the rotational speed calculated by the arithmetic unit (20). Any actual rotational speed can be output by means of a first (251) of the at least two signal outputs (25) and only those actual rotational speeds are output by means of a second (252) of the at least two signal outputs (25) whose values are comprised by a predetermined rotational speed range which is a proper subset of an actual rotational speed operating range of the rotating machine part (5). The second signal output (252) allows outputting rotational speed values with a greater exactness if they are contained in the predetermined rotational speed range, especially in a range around a nominal rotational speed.