The direct current system of the core network of communication system using double electrical power systematic two-circuit access is the access pattern of power source which appears in the recent two years

it is also the correspondence of operators? pursue in redundant reliability and safely fixed pattern

however

how to solve the pressure difference question between the systems? Whether the solutions are safe and reliable? And so on. Several questions also wait for further inquiry. This article proposed some of the disadvantages in using the double power source access pattern in current direct current system

simultaneously has analyses and discussed the security and the reliability of this kind of pattern.