韓國HYUNDAI 蓄電池N120/CMF120   12V120AH啟動UPS電源There is a dedicated battery measuring instrument for judging the of batteries, but most users rarely have such instruments and only have one multimeter. The following are a summary of how to judge the of a battery during maintenance, for reference 1. Judging from appearance: observe whether there is deformation, protrusion, leakage, rupture, burning, or oxide leakage at the screw connection. 2. On load measurement: If there are no abnormalities in the appearance, the UPS operates in battery mode with a certain amount of load. If the discharge time is significantly shorter than the normal discharge time, and after 8 hours of charging, the normal standby time cannot be restored, it is judged that the battery is aging. 3. Measure with a multimeter: A. Measure in battery discharge mode: Measure the voltage at each battery terminal in the battery pack. If one or more battery terminals have a voltage that is significantly higher or lower than the nominal voltage (12V/cell), determine battery aging. B. Measurement in mains mode: The charging voltage of each battery end in the battery pack. If the charging voltage of one or more batteries is significantly higher or lower than the other voltages, it is judged that the battery is aging.