Because the wavelet has the characteristic of multi-resolution analysis

and has the ability to represent signal of local information in time domain and frequency domain.The research is based on wavelet analysis of wavelet transform for fault diagnosis of turbidity sensor

singularity and the singular values are found out

and fault time and serious condition of the sensor are detected.Simulation results show that this method can effectively detect and identify faults of turbidity sensor

which has characteristics of sensitivity and high rate of fault diagnosis.