The schematic diagram of the system is given in the figure. It provides a double feed to each feeder circuit, opening one breaker under maintenance or otherwise does not affect supply to any feeder. But this system has two major disadvantages. One as it is closed circuit system it is next to impossible to extend in future and hence it is unsuitable for developing system. Secondly, during maintenance or any other reason if any one of the circuit breaker in ring loop is switch of reliability of system becomes very poor as because closed loop becomes opened. Since, at that moment for any tripping of any breaker in the open loop causes interruption in all the feeders between tripped breaker and open end of the loop.