Ups-watt (W) and voltammetry (VA): Two confusing concepts

Many people do not know that the UPS capacity should be expressed by Watt or Volt-Ampere. Many ups manufacturers cannot tell the difference between the two concepts, and even equate W and VA, which increases the confusion of understanding. UPS capacity is always represented by va rather than W. W indicates the UPS capacity, probably because the UPS capacity is small.
UPS users are familiar with the concept of Watt, but VA can more accurately represent the matching degree between ups and load capacity, because the output capacity of UPS is determined by the current value (), therefore, VA is more appropriate.
The W value is always less than or equal to the VA value.
The conversion relationship is as follows:
Watts (Watt value) = VA * Power Factor = volts * amps * Power Factor
Amps = load current
Power Factor: Power Factor. Its value ranges from 0 to 1.
The power factor ranges from 0 ~ Between 1, it indicates the percentage of load current (Watts.
Only the power factor of electric heaters and bulbs is 1. For other devices, some load current is only circulating in the load, and no work is done. This part of current is harmonic or reactive current, which is caused by load characteristics. It is important to understand that the VA value is larger than the W value because of this current, and the W value is considered as a special case when the power factor is 1.
The W-watt value of a computer is 60 ~ of its va value ~ 70%, in fact, all the modern computer's switching power supply is capacitive, and its power factor value is 0.6 ~ 0.7. Individual machines tend to be 0.6, while mainframes tend to be 0.7. A new type of Power Supply called Power Factor Self-tuning has been developed recently. Its power factor value is 1. This type of power supply is likely to be widely used in the future, but it is rarely seen in the market.
Most ups manufacturers use W to indicate capacity, but they actually refer to va. When the ups manufacturer points out the rated W value without marking the power factor and the rated va value, the user can assume that this is the W value (equal to the VA value) when the power factor is 1, and the manufacturer actually refers to the ups rated va value. The actual W value for Computer load is 60 ~ 70%, so a w ups can drive a W bulb, but can only drive a W computer.
The capacity of most computer devices is represented by va, and recently some computers are represented by W (the most famous DEC and IBM ). But in general, there are still a lot of VA. Therefore, the ups uses Va to indicate that the capacity can better reflect the matching degree with the load.
The UPS value is rated as Va to avoid confusion. When a UPS value is marked with W, the actual W capacity of the Computer load is 60 ~ 100% (usually 60%) while the VA value is 100 ~ 130% of the calibration W value. When a UPS instance marks the rated va value, the actual va value for the Computer load is equal to the marked value, and the W value is 60 ~ of the marked value ~ 70%.