APC UPS

What is the lifespan of a dedicated UPS (Uninterruptible Power Supply) for server racks in a data center ? ( Part 5)

① Battery automated management software performs charge/discharge management on the battery every 3-4 months when the mains power is normal. Discharging to 20% and automatically switching between equalization and float charging fully activates the lead-acid molecules, significantly extending battery life. Our factory conducted a test where a battery discharged to 20% and left at 80% could cycle 1500-2500 times, while a battery discharged to 100% with a 10.5V termination voltage could only cycle 300 times before its lifespan ended.

② During discharge, each battery pack is constantly monitored, including the voltage, current, and temperature of each battery. The battery voltage is adjusted to compensate based on the battery temperature.

③ Battery discharge log to prevent battery failure diagnosis;

④ The charging current is set at 0.1C, and the current can be set from 1 to 100A.

9. Real-time monitoring: Modern intelligent UPS power supplies are equipped with features such as communication with microcomputers and program control. By installing the corresponding software on a microcomputer, connecting the UPS power supply via a serial/parallel port, and running the program, communication between the microcomputer and the UPS power supply can be achieved. Generally, it has functions such as information query, parameter setting, timer setting, automatic shutdown, and alarm. For example, Winpower. Then, by connecting the UPS power supply to the computer via a dedicated serial control cable, and communicating via RS232 and RS485 protocols, the UPS power supply can automatically shut down when there is no mains power input or the battery is low. Furthermore, it can simultaneously monitor multiple UPS power supplies connected to the same serial port.

10. Choosing a suitable UPS installation location is crucial. The UPS should be placed in a well-ventilated area, away from water, flammable gases, and corrosive agents. The ambient temperature should be maintained between 0 and 40°C. If the UPS is disassembled and used at low temperatures, condensation may occur. Once the ambient temperature exceeds 25°C, the battery life will be halved for every 10-degree increase. Currently, UPS power supplies generally use maintenance-free sealed lead-acid batteries with a design life of approximately 5 years.

UPS power supplies should not be placed on their side; the air inlet and outlet should be kept unobstructed. When connecting loads to the UPS, the loads must be turned off first, then the connections made, and then the loads turned on one by one. Inductive loads such as electric motors and photocopiers must never be connected to the UPS to avoid damage. When connecting the UPS to a dedicated socket with overcurrent protection, the socket should be connected to the protective ground. The UPS output may be energized regardless of whether the input power cord is plugged into a mains outlet. To deactivate the UPS, turn off the switch first, then disconnect the mains power supply.

11. UPS Power Supply Installation Precautions: Safety precautions must be taken when connecting the UPS output power supply. Because the UPS output voltage and current are relatively high, care must be taken to prevent electric shock. When replacing batteries, first turn off the UPS power supply and disconnect it from the mains power. Use a screwdriver with an insulated handle; do not place tools or other metal objects on the batteries. Small sparks at the connectors when connecting battery cables are normal and will not harm personal safety or the UPS power supply. Never short-circuit or reverse the positive and negative terminals of the battery. When replacing batteries, do not replace them individually; replace the entire battery pack. Furthermore, it is forbidden to combine batteries of different amperage ratings or brands.

12. Regular Maintenance: This refers to the batteries inside the UPS power supply. As a core component of the UPS, they deserve careful protection and regular maintenance. If there is a prolonged period of uninterrupted power supply, the power supply must be manually interrupted periodically (every three months) to allow the UPS to discharge under load. Because the power has never been interrupted, you may assume it is working normally. However, once the power is interrupted, it can only provide a very short delay or even no delay at all. This is because the UPS batteries are in a float charging state for an extended period.