Abstract: The present invention provides a method of monitoring a cyclic system comprising a plurality of cyclic means, comprising measuring a single parameter for the complete cyclic system, and, during a learning mode, cycling the cyclic system a plural number of times, and from the measured value of the parameter, providing a range of acceptable values, and during a subsequent monitoring mode comparing the measured value of said parameter with said range of values, and providing an output signal if the measured value of the parameter is outside said range of values.