Research on the Monitoring Technique of Non-Contact Running Status of Cooling Tower Fan Blades

This paper presents a new monitoring method of non-contact blade status-blade tip timing monitoring method based on the principle of discontinuous phase principle, and a new monitoring system of non-contact running status of cooling tower fan blades is developed on the basis of the technology of single-chip microcomputer(SCM) and the blade tip timing monitoring method. The monitoring system is controlled by the SCM and has real-time monitoring to the blade. The pulse signal which is collected by the sensor is processed by the SCM. Through using the timing and interrupt function of SCM, the pulse signal is analysed and processed, when the blade breaks down and deforms, the system will shut down the fan and output a forecast alarm, so the blade accident will be prevented. It is proved that the monitoring method can greatly improve the reliability of the fan running status and the fault diagnosis and effectively prevent the default of the blades, so the monitoring system has a wide application value.