Method and apparatus for safely disconnecting to the electric drive, such as a frequency-controlled three-phase crane motors

摘要

This invention drive or ascent and descent speed obstacle of the electric drive device which becomes independent there is no delay by maintaining safe performance, was recognized, at the same time in order disconnection to do the electric drive device to be used in order, was constituted, the electric drive device safely it regards the method and the device in order disconnection to do. The signal of the sensor (7.1, 7.2, 8.1 and 8.2) it is detected redundantly, the appraisal device (2.1 and 2.2) the threshold where the inside is beforehand selected by comparison with redundantly, the electric drive device (12) when it exceeds the threshold which is selected beforehand, the electric drive device (12) disconnection is done safely redundantly without using the mechanical position device.