This paper presents the electrical performance of DC chopper loaded by large DC motor and large batteries of different sizes or connected with DC supply in series with it. The motor is represented by an inductor where the battery is represented by different values from 12v to 108v. The DC source supplied the load has a value of 110v.The load motor can be connected with a different DC supply series with it in spite of batteries. The aim of this research is the use of an injected DC supply connected in series with the large motor for protection purpose. The results of this research can be applied for the protection of motors at standstill conditions without the interruption of the power supply of the motor. The research illustrates that batteries are preferred than the DC supply. This research is applied in solar energy laboratory on filling machine. It may be used for filling any liquids in bottles automatically. A microcontroller programmed and operates as a control of the filling process. The DC motor under investigation represents the drive of the controlled filling machine. An electronic circuit is designed with microcontroller construct the filling machine controller.