FIGURE 2.1 DC UPS For the Kenyan case, the system designed should supply power to the load at 240 Vrms and 50Hzfrequency. This system cannot provide complete power protection and the mode of operation has to be changed on power failure, i.e. from line to battery and as such its application is restricted to small systems where operation is not highly critical. Though the system is simple and economical, it has a major disadvantage that if some fault develops in the charger or rectifier the whole system gets out of order and no power is available even when the power supply is present. An uninterruptible dc power system consists of: literature review An automatic battery charger- To charge and protect the battery Battery- to the power to be used when the mains are not available Monitoring system- To display on the battery levels. An automatic transfer switch- to switch the load between the mains and backup power depending on which is available. 2.2 STORAGE BATTERY A battery is an electrical device is a combination of several electrochemical cells, used to convert stored chemical energy into electrical energy or vice versa for rechargeable batteries. A rechargeable battery is made up of several cells. Since a single cell is basically 2 Volt, 12Volt
FIGURE 2.1 DC UPS For the Kenyan case, the system designed should supply power to the load at 240 Vrms and 50Hzfrequency. This system cannot provide complete power protection and the mode of operation has to be changed on power failure, i.e. from line to battery and as such its application is restricted to small systems where operation is not highly critical. Though the system is simple and economical, it has a major disadvantage that if some fault develops in the charger or rectifier the whole system gets out of order and no power is available even when the power supply is present. An uninterruptible dc power system consists of: literature review An automatic battery charger- To charge and protect the battery Battery- to the power to be used when the mains are not available Monitoring system- To display on the battery levels. An automatic transfer switch- to switch the load between the mains and backup power depending on which is available. 2.2 STORAGE BATTERY A battery is an electrical device is a combination of several electrochemical cells, used to convert stored chemical energy into electrical energy or vice versa for rechargeable batteries. A rechargeable battery is made up of several cells. Since a single cell is basically 2 Volt, 12Volt
UNINTERRUPTED%20DC%20POWER%20SUPPLY.docx