On radiated and conducted disturbances of a crane safety equipment

The paper deals with the designing, realization and testing of a crane safety equipment designed to automatically interrupt the operation of the lifting gear. Firstly a brief presentation of the crane safety equipment is made. Two technical solutions concerning the power sources for the transducers included in the crane safety equipment were studied. Electromagnetic interferences with the supplying network can appear due to different operational contexts. Therefore there were designed and realized filters on the supplying side in order to reduce the electromagnetic disturbances introduced by the crane safety equipment. LT Spice was used to achieve the frequency characteristics for the network filter. In order to reduce the disturbances conducted along the cables connecting the transducers for force and arm position, LCR filters were designed, realized and mounted. In order to evaluate the effect of the equipment implemented in order to diminish/cancel the disturbances, experimental determinations of the conducted and radiated disturbances were made. The EMC limits were met according to the standards.