Cable Drum

The signals representing angle and length of a telescopic crane are important measuring data. Determination of such measuring data is performed by means of tilt angle and rope length transmitters. The determination of the jib angle is performed by a magnetically damped pendulum system, the swing of which is measured with a redundant high-resolution conductive plastic potentiometer. The output signal is provided in form either of two resistance signals or via the built-in signal converter in form of two current or voltage signals. Linear measurement is performed according to the draw wire measuring principle. One makes use of a multiwire measuring cable, which is wound multilayered on a cable reel provided with a pullback spring. A mechanical spindle lead screw nut ensures, that the rope is rewound and unwound exactly layer-by-layer. The number of drum revolutions, being proportional to the measured length is determined by a redundant potentiometer system voltage or current output.