In this paper, photovoltaic system (PVS) contains solar cells array, lead acid battery and a load is constructed. The lead acid battery is represented by the agricultural tractor battery. The PVS load is the agricultural tractor electrical circuits . These circuits are the lighting circuits , injunction  pump and accessories such as laser system used for land leveling.    The main objective of the research is the evaluation of the electrical performance of each element of the PVS. The system is constructed and operated during five sun shin periods. During these periods the evaluation of the performance for each PVS, elements is accomplished. The research shows that the solar calls array is a nonlinear element. Hence, its performance ( I,V ) is a  nonlinear.  This means that its output voltage is not constant on the load. Consequently, the flocculation of the tractor electrical circuit operation will be occurred. The research shows that, the tractor lead acid battery may solve the last problem. The electrical performance of the tractor lead acid battery during the sun shine periods is determined. Two levels of battery voltage (6V,12V) are selected for the evaluation . The selected level represent that the laser tractor batteries are such that, two 6 volt series batteries each 80 Ahr or  12 volt 155 Ahr  one battery . The research shows that the tractor battery plays a good role for staplizing  the voltage of the tractor electrical circuits . This leads to good improvements for the tractor system operation and for reserving the battery charging at predetermined levels. The last improvements prevent the voltage flocculation on the tractor circuits and the   accessories connected to the battery. This leads to good performance of the laser system connected to the tractor electrical system.