How can I use matlab wavelet toolbox given list of voltages for power quality analysis?

Hello everyone. I have a problem right now. I am doing power quality analysis using matlab wavelet toolbox. I have the data, which is the excel file of voltages for each coordinates of fault points. Right now, I do not know how to get the wavelet signal for each of the voltages given. Could anyone help me and give a full tutorial on how I can get through this? Thank you very much.