Abstract: A method with respect to a system that includes an electrical motor and a speed output unit, and the electrical motor is followed by a gear, wherein the following acts are performed by a processor of a controller of a motor drive: monitoring a first set of frequencies from the system over a measurement period when the system is in a known good operating condition; storing the first set of monitored frequencies or derivatives thereof as reference data in a long-term storage system, monitoring a second set of frequencies from the system over a measurement period when the system is in an unknown operating condition, comparing the second set of monitored frequencies with the first set of monitored frequencies in a frequency domain and in the frequency domain, detecting changes between corresponding frequencies resulting from the second set of monitored frequencies and the first set of monitored frequencies.

Abstract: An apparatus for collecting energy in connection with a sheave system in a hoisting apparatus provided with a sheave system. The apparatus includes at least one generator including a rotor and at least one stator. The rotor is connected rigidly to a sheave of the sheave system, and the at least one stator is connected rigidly to the sheave system such that when the load of the hoisting apparatus is rising or lowering, said at least one sheave rotates, whereby the rotor rotates simultaneously but the stator does not rotate, whereby electric energy is induced in the stator. The apparatus further includes electric energy storage, a device for modifying induced electric energy and storing it in energy storage; and a device for supplying energy from the energy storage to at least one consumption device. The consumption device may be, for example, a working lamp, sensor, measuring device, communications device, signal device, charging plug or a combination of these mounted in connection with the sheave system.

Abstract: A method comprising performing the following steps with respect to a system that comprises an electrical motor and a speed output unit, and the electrical motor is followed by a gear, wherein the following acts are performed by a processor operationally coupled to the system: monitoring a first set of frequencies from the system over a measurement period when the system is in a known good operating condition; storing the first set of monitored frequencies or derivatives thereof as reference data in a long-term storage system, monitoring a second set of frequencies from the system over a measurement period when the system is in an unknown operating condition, comparing the second set of monitored frequencies with the first set of monitored frequencies in a frequency domain and in the frequency domain, detecting changes between corresponding frequencies resulting from the second set of monitored frequencies and the first set of monitored frequencies, wherein the electrical motor is driven by a motor drive, and

Abstract: Method/apparatus for performing the following acts on a system that includes an electrical motor followed by a gear, and a speed output unit: monitoring a first set of frequencies from the system over a measurement period when the system is in a known good operating condition; storing the first set of monitored frequencies or derivatives thereof as reference data in a long-term storage system; monitoring a second set of frequencies from the system over a measurement period when the system is in an unknown operating condition; comparing the second set of monitored frequencies with the first set of monitored frequencies in a frequency domain; in the frequency domain, detecting changes between corresponding frequencies resulting from the second set of monitored frequencies and the first set of monitored frequencies.

Abstract: Method/apparatus for performing the following acts on a system that includes an electrical motor followed by a gear, and a speed output unit: monitoring a first set of frequencies from the system over a measurement period when the system is in a known good operating condition; storing the first set of monitored frequencies or derivatives thereof as reference data in a long-term storage system; monitoring a second set of frequencies from the system over a measurement period when the system is in an unknown operating condition; comparing the second set of monitored frequencies with the first set of monitored frequencies in a frequency domain; in the frequency domain, detecting changes between corresponding frequencies resulting from the second set of monitored frequencies and the first set of monitored frequencies.

Abstract: An apparatus for collecting energy in connection with a sheave system in a hoisting apparatus provided with a sheave system. The apparatus includes at least one generator including a rotor and at least one stator. The rotor is connected rigidly to a sheave of the sheave system, and the at least one stator is connected rigidly to the sheave system such that when the load of the hoisting apparatus is rising or lowering, said at least one sheave rotates, whereby the rotor rotates simultaneously but the stator does not rotate, whereby electric energy is induced in the stator. The apparatus further includes electric energy storage, a device for modifying induced electric energy and storing it in energy storage; and a device for supplying energy from the energy storage to at least one consumption device. The consumption device may be, for example, a working lamp, sensor, measuring device, communications device, signal device, charging plug or a combination of these mounted in connection with the sheave system.