Abstract: Based on the statistical analysis of electrical equipment failures during actual operation, temperature is defined as the variable basis for planned maintenance cycle. Temperature variable is proposed to be included in the formulation of the electrical equipment planned maintenance cycle. Taking the failure-free operating time of the equipment as research object, an electrical equipment failure probability distribution model is constructed in three conditions, which is finally determined by adopting maximum likelihood estimation and K-S goodness-of-fit test method. Combined with the polynomial curve fitting method, the relationship between temperature variables and the parameters of the above model is determined, on this basis, the electrical equipment failure condition probability distribution model is established. With reliability as the constraint condition, the planned maintenance cycle of electrical equipment is formulated. Taking Wuxi metro access control workstation electrical equipment as an example, the feasibility of the method is verified.