Before the appraisal you should have an idea of the extent to which the various salary-setting factors apply to you and your performance. Both your perception and that of your manager are to be expressed during the appraisal. Make sure that the appraisal is documented.
After the salary review, your manager is to explain your new salary. This is crucial in order for the connection between work output and salary development to have an impact. It must be possible to justify both a positive and a less positive salary development.
Contact your line manager or the human resources officer within your department/faculty or equivalent.