A Comprehensive Guide to UPS Uninterruptible Power Supply ( Part 16)

5.1 Professional Analysis of Core Technical Parameters

(1) Rated power (VA/W): The core load parameter of UPS power supply, which is divided into apparent power (VA) and active power (W). The conversion factor between the two is generally 0.8. The core principle of selection is: the rated load power of the equipment must be greater than the total power of all downstream equipment, and 20%-30% redundant load should be reserved to avoid full load and overload operation, and to ensure the stability and service life of the equipment.

(2) Output waveform: It is divided into sine wave, square wave and stepped wave. Among them, the pure sine wave output is the industry standard high-quality waveform, which is suitable for all precision electronic equipment; the square wave and stepped wave are only suitable for ordinary resistive loads and cannot be used for precision loads such as servers, inverters, and medical equipment. For high-precision scenarios, pure sine wave UPS equipment must be selected.

(3) Switching time: refers to the response time of switching from mains power failure to battery power. Online UPS has a zero-millisecond switching time, which is suitable for all high-precision scenarios; online interactive switching time is ≤4 milliseconds; standby switching time is ≤10 milliseconds, which can be adapted to ordinary scenarios, but are prohibited from use in precision scenarios.

(4) Voltage regulation accuracy: High-quality online UPS has a voltage regulation accuracy of ≤±1%, which can achieve ultimate power optimization; online interactive UPS has a voltage regulation accuracy of ≤±5%; standby UPS has no precise voltage regulation capability and can only be basically adapted.

(5) Backup power supply duration: It is divided into the built-in battery duration of the standard machine and the external battery duration of the long-lasting machine. The backup power duration of the standard machine is 5-15 minutes, which can meet the requirements for safe shutdown of the equipment; the long-lasting machine can achieve emergency power supply for 1 hour, 2 hours, 4 hours, 8 hours or even longer through an external battery cabinet, which is suitable for long-term power outage scenarios.

(6) Working efficiency: refers to the power conversion efficiency of UPS power supply. High frequency online type has an efficiency of ≥96%, with excellent energy saving; power frequency online type has an efficiency of ≥93%; standby type and online interactive type have an efficiency of 90%-95%. The higher the efficiency, the lower the operating energy consumption, and the more energy-saving it is in long-term use.

(7) Protection level: For industrial and outdoor scenarios, the higher the protection level IP value, the stronger the dustproof, moistureproof, waterproof and corrosionproof capabilities, and the more outstanding the ability to adapt to harsh working conditions.