What are the common faults and troubleshooting methods of UPS that use lithium batteries?

　　Fault 1: The voltage of the lithium battery UPS is low, but the voltage of the lithium battery still cannot be charged after charging for more than ten hours.

　　Troubleshooting method: The failure of not charging is very harmful, and it is likely that the battery is discarded in advance because it cannot be charged for a long time. Disconnect the charging circuit from the battery, and determine the fault by measuring the no-load voltage of the charging circuit.

　　Fault 2: After the UPS is turned on, there is no display on the panel, and the lithium battery does not work.

　　Follow the steps to troubleshoot: (1) If the mains input fuse is intact, check whether the battery fuse is burned. (2) Check whether the mains detection circuit works normally. (3) Check whether the battery voltage detection circuit is normal after there is no abnormality.

　　Fault 3: Turn on the UPS when the mains power supply is normal, the inverter working indicator flashes, and the buzzer emits intermittent beeps. The UPS can only work in the inverter state and cannot be converted to the mains working state.

　　Follow the steps to troubleshoot: (1) Check whether the mains input fuse is damaged. (2) Check whether the output of the mains rectifier filter circuit is normal. (3) Check whether the mains detection circuit is normal. (4) Check whether the control output from the inverter power supply to the mains power supply is normal.

　　Fault 4: UPS can only be powered by the city power supply and not by inverter power supply.

　　Follow the steps to troubleshoot: (1) Check whether the battery voltage is too low. (2) Whether the battery fuse is in good condition (3) Check whether the battery voltage detection circuit is normal. (4) Check whether the control output from the mains to the inverter power supply is normal.

　　The above are the more common fault problems and troubleshooting methods for UPS systems using lithium batteries.

　　Lithium-ion battery (LIB) has become the main energy storage solution in modern social life. Among them, lithium iron phosphate batteries are a perfect replacement for lead-acid batteries, and are the first choice for grid-connected peak shaving, off-grid energy storage, photovoltaic energy storage, UPS, data centers and other industries.