The results of numerical simulation of the dynamical characteristics of an electromagnetic pulse actuator with respect to the condition of its permissible heating are presented. The short-time operation mode is considered. This mode is featured by constant power applied to the actuator and the necessity to switch off the actuator when its temperature has achieved the limit value and then to cool the actuator until ambient temperature. The subject of research is the development of the algorithm for numerical simulation of the permissible operation time of the electromagnetic actuator with respect to the permissible heating condition and output energy. The object of the research is the electromagnetic pulse actuator that makes reciprocating motion. The electromagnetic actuator has a moveable part controlled by electromagnetic forces generated by the excitation coil powered by pulse current. The moveable part is reversed by mechanical forces generated by the return spring. The research makes it possible to obtain the relation between the electromagnetic actuator output indicators and its operating period. The algorithm for numerical simulation of the operation process during a short-time mode is presented. The algorithm is verified with the electromagnetic pulse actuator model.