Abstract: Right setting about protection and limit functions of microprocessor excitation adjuster is important to the experiment. The integrated automation experiment of power system was offered by Three Gorges University. And WDT-III integrated automation laboratory table of power system which uses WL-04B excitation system is used. This paper analyzes the considerable problems in setting the parameters of function units of microprocessor excitation adjuster for experiments. And the principle of parameters setting is proposed and then researched.