Four maintenance methods for UPS batteries

Maintain a suitable ambient temperature

Generally speaking, the factor that has the greatest impact on battery life is ambient temperature. Generally, the optimal ambient temperature required by battery manufacturers is between 20-25℃. Although the increase in temperature improves the battery's discharge capacity, the price paid is that the battery's life is greatly shortened. According to test measurements, once the ambient temperature exceeds 25℃, the battery life will be shortened by half for every 10℃ increase in temperature. At present, the batteries used in UPS are generally maintenance-free sealed lead-acid batteries, and the design life is generally 5 years, which can only be achieved in the environment required by the battery manufacturer. If the specified environmental requirements are not met, the length of its life will vary greatly. In addition, the increase in ambient temperature will lead to an increase in the chemical activity inside the battery, thereby generating a large amount of heat energy, which in turn will cause the ambient temperature to rise. This vicious cycle will accelerate the shortening of the battery life.

Regular charging and discharging

The floating charge voltage and discharge voltage of the UPS power supply have been adjusted to the rated value before leaving the factory, and the discharge current increases with the increase of the load. The load should be adjusted reasonably during use, such as controlling the number of electronic equipment such as microcomputers. In general, the load should not exceed 60% of the UPS rated load. Within this range, the battery discharge current will not be over-discharged.

Because UPS is connected to the mains for a long time, in an environment with high power quality and rarely power outages, the battery will be in a floating charge state for a long time, which will reduce the activity of the battery's chemical energy and electrical energy conversion over time, accelerate aging and shorten its service life. Therefore, it should be fully discharged once every 2-3 months, and the discharge time can be determined according to the battery capacity and load size. After a full load discharge, recharge for more than 8 hours as required.

Using the communication function

At present, most large and medium-sized UPS have operable functions such as communication with microcomputers and program control. Install the corresponding software on the microcomputer, connect the UPS through the serial/parallel port, run the program, and then you can use the microcomputer to communicate with the UPS. Generally, it has functions such as information query, parameter setting, timing setting, automatic shutdown and alarm. Through information query, you can obtain information such as mains input voltage, UPS output voltage, load utilization, battery capacity utilization, internal temperature and mains frequency; through parameter setting, you can set the basic characteristics of UPS, battery life and battery exhaustion alarm. Through these intelligent operations, the use and management of UPS power supply and its battery are greatly facilitated.

Replace waste/damaged batteries in time

At present, the number of batteries equipped in large and medium-sized UPS power supplies ranges from 3 to 80, or even more. These individual batteries are connected through circuits to form a battery pack to meet the needs of UPS DC power supply. During the continuous operation of the UPS, due to differences in performance and quality, it is inevitable that individual batteries will deteriorate in performance and the storage capacity will not meet the requirements and be damaged. When one or some batteries in the battery pack are damaged, the maintenance personnel should check and test each battery to eliminate the damaged batteries. When replacing new batteries, you should try to buy batteries of the same model from the same manufacturer. It is forbidden to mix acid-proof batteries and sealed batteries, and batteries of different specifications.

This article provides four methods to extend the working life of UPS batteries, which can be summarized in four sentences: appropriate temperature, regular charging and discharging, making good use of communication functions, and timely replacement of damaged batteries. There is no big or small knowledge in the study of power supply. As long as you pay attention and observe, you can summarize various characteristics and methods to facilitate our design.