The battery pack is an essential component of the UPS system, and its cost is relatively high. Therefore, when the UPS system has been in operation for a certain period, and it becomes necessary to 

ensure the system's reliability by replacing the battery pack, users often inquire about the standards and requirements for battery replacement. In fact, there are no strict requirements for battery replacement,

 but we have compiled two reference indicators related to battery life for users to consider.

1. Float life is the number of years a battery can be used under standard temperature and continuous float charge conditions without discharging below 80% of its rated capacity.

2. The number of 80% deep cycle charge and discharge cycles is the number of times a full-capacity battery can be discharged to 80% of its rated capacity and then fully recharged for reuse.

3. Therefore, according to relevant regulations, it is recommended to replace the battery pack when the rated capacity of the battery pack falls below 80% for either of these two conditions.

4. How can one determine the capacity of the battery pack? The battery capacity can be determined by using a battery internal resistance tester to measure the current internal resistance of the battery. 

When the internal resistance of the battery increases to 1.5 times the factory internal resistance, it indicates that the battery capacity has dropped below 80%, and it is advisable to replace the battery pack.