Power Factor and Single Phase Transformer

However, since the transformer is attached to a 480v line, the secondary current would be the same as the primary current, which would be 1/4 of the secondary current or 43.5A. This is because the transformer ratio is 4:1. In summary, the secondary current in a single-phase distribution transformer attached to a 480v line and supplying 120v to a 16kW reactive load with a power factor angle of 40° would be 174A, and the primary current would be 43.5A due to the 4:1 transformer ratio.
  • #1
fatmoe
6
0
What is the secondary current in a single-phase distribution transformer that is attached to a 480v line when the transformer is supplying 120v to a 16kW reactive load with a power factor angle of 40°.

So I have kVA = 16kW/cos 40 = 20.89kVA

Is = 1000 * 20.89kVA / 120v = 174A.

I don't know if I did this question correctly. Do you not have to use the 480v for anything?
 
Physics news on Phys.org
  • #2
Hi fatmoe,

In future please retain and use the Homework Format Template provided when you start a new thread in the Homework Help sections of PF.

fatmoe said:
What is the secondary current in a single-phase distribution transformer that is attached to a 480v line when the transformer is supplying 120v to a 16kW reactive load with a power factor angle of 40°.

So I have kVA = 16kW/cos 40 = 20.89kVA

Is = 1000 * 20.89kVA / 120v = 174A.

I don't know if I did this question correctly. Do you not have to use the 480v for anything?

Your calculation looks fine for finding the magnitude of the current in the secondary.
 

Related to Power Factor and Single Phase Transformer

1. What is power factor and why is it important?

Power factor is a measurement of how efficiently electrical power is being used in a circuit. It is important because a low power factor can result in wasted energy and additional costs for consumers.

2. How is power factor calculated?

Power factor is calculated by dividing the real power (kW) by the apparent power (kVA). This calculation results in a number between 0 and 1, with a higher number indicating a more efficient use of power.

3. What is the significance of power factor in single phase transformers?

In single phase transformers, power factor is important because it affects the efficiency and performance of the transformer. A low power factor can lead to increased energy loss and decreased voltage regulation.

4. How does a single phase transformer affect power factor?

A single phase transformer can improve power factor by adjusting the voltage and current levels in the circuit. By stepping up or stepping down the voltage, the transformer can help balance the real and reactive power, resulting in a higher power factor.

5. How can power factor be improved in single phase transformer circuits?

Power factor can be improved in single phase transformer circuits by using power factor correction devices, such as capacitors, to offset the effects of inductive loads. Properly sized and placed capacitors can help reduce reactive power and improve the overall power factor of the circuit.

Similar threads

Engineering Calculating Power Lost in a Resistor (within Transformer Circuit)
    • Engineering and Comp Sci Homework Help
Replies
4
Views
1K
Engineering Intro to Power Systems: Calculating Power
    • Engineering and Comp Sci Homework Help
Replies
7
Views
1K
Understanding Load kVA and Power Factor in Three Phase Transformers
    • Engineering and Comp Sci Homework Help
Replies
1
Views
2K
Single phase transformer question
    • Engineering and Comp Sci Homework Help
Replies
6
Views
3K
Maximum power from a transformer
    • Electrical Engineering
Replies
8
Views
1K
Sizing an Isolation Transformer for a DC Power Supply
    • Electrical Engineering
Replies
8
Views
1K
Transformers and Active/Reactive power question from HW
    • Engineering and Comp Sci Homework Help
Replies
7
Views
2K
Engineering I can't figure out what's going on with these sqrt[3] terms (3-Phase AC Mains question)
    • Engineering and Comp Sci Homework Help
Replies
2
Views
2K
Optimizing Power with Parallel Transformers
    • Engineering and Comp Sci Homework Help
Replies
1
Views
1K
Alternator run at zero power factor lagging
    • Electrical Engineering
Replies
2
Views
620

Hot Threads

Recent Insights

Back
Top