What is "Apparent Power" (VA)?

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Apparent power, measured in volt-amperes (VA), is crucial for understanding how different loads consume power, particularly when selecting an uninterruptible power supply (UPS). It combines both real power (watts) and reactive power, which is essential for devices like motors that require both types for proper operation. A 100 VA UPS can support a 100-watt resistive load but may not adequately power a 100-watt motor due to its additional reactive power needs. The distinction between VA and watts is significant, as it affects the efficiency and performance of electrical systems. Understanding apparent power helps ensure appropriate UPS selection for various applications.
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In school I learned about impedance:
where..

$$Z^2 = R^2 + X_{net}^2$$

but this was the only triangle I recall learning about.
The picture below I definitely do not recall.

1615653994311.png

from this Link

The only quantity I am familiar with is the x-axis (Power).

If someone could explain apparent power and its importance with finding an appropriate UPS device, please throw me a bone. ty
 
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Read that article that @gleem posted for you.

For a dead simple example, a 100 VA UPS could power a 100 w resistance heater, but not a 100 w motor. That's why it is important.

In a resistance, the imaginary power is zero, so VA and power are the same thing. That's what you are used to.

The motor needs both real power (watts) and imaginary power, so the VA is the complex sum as shown in the diagram you posted in #1.
 
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