Under normal conditions, every parameter of rectifier modules and distribution unit are all under control of the monitoring module, operating according to the pre-set parameter or user’s commands. If AC mains fault, the system will be powered by the battery. When the battery discharge, the terminal voltage of the battery starts to descend. Until the voltage is under 42V±0.5V, the monitor reports DC under voltage alarm signal and cuts off the load output then the power system stops working. After the external AC mains recover, the system will resume to the normal work state (all above monitoring data is system default values that users can reset). Except for battery over-discharge protection, battery or load over-temperature protection is prohibit under default, users can send command to activate or inactivate according to the demanding. The operating temperature is 55°C or more but power derating will be employed in case of operating temperature is over 55°C. Regarding the demand of telecom rectifier system, we can customize the requirements by using the following specification :