What is "Apparent Power" (VA)?

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In summary, the conversation discusses the concept of impedance and its formula, as well as the importance of power factor and the difference between real power and apparent power. The conversation also mentions the use of UPS devices and provides an example to demonstrate the importance of considering both real and imaginary power.
  • #1
iScience
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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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  • #3
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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Related to What is "Apparent Power" (VA)?

What is "Apparent Power" (VA)?

Apparent power, also known as VA (volt-ampere), is a measure of the total power in an electrical circuit. It is the combination of both real power (measured in watts) and reactive power (measured in volt-amperes reactive or VAR).

How is apparent power different from real power?

Real power is the actual power consumed in an electrical circuit, while apparent power is the total power present in the circuit. Real power is the useful power that is converted into work, while apparent power includes both real power and reactive power.

Why is apparent power important?

Apparent power is important because it is used to determine the capacity of electrical equipment, such as transformers and generators. It also helps in calculating the efficiency of electrical systems and identifying potential issues, such as power factor problems.

How is apparent power calculated?

Apparent power is calculated by multiplying the voltage (V) by the current (A) in an electrical circuit. The unit of measurement for apparent power is volt-ampere (VA).

What is the relationship between apparent power and power factor?

Power factor is the ratio of real power to apparent power. A high power factor indicates that the circuit is using power efficiently, while a low power factor can result in wasted energy and increased costs. Apparent power and power factor are inversely related, meaning that as apparent power increases, power factor decreases.

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