The main aim of this work is to develop a Dynamic Voltage Scaling (DVS) algorithm for real- time system with resource constraints and the system thus developed is fault tolerant as well. The system is assumed to contain independent periodic tasks. Earliest Deadline First scheduling algorithm is considered in this. The algorithm helps in meeting the deadlines of all the tasks and also ensures that the total power consumption is minimized. The other objective is to develop a fault tolerant system. The proposed system is designed to handle hardware faults. Thus the proposed system is energy efficient and reliable.