AC Power Calculator Form
Example Data Table
| Case | System | Connection | Voltage (V) | Current (A) | PF | Efficiency (%) | Real Power (kW) | Reactive Power (kVAR) | Apparent Power (kVA) |
|---|---|---|---|---|---|---|---|---|---|
| Example 1 | Single Phase | Direct | 230.00 | 12.00 | 0.92 | 96.00 | 2.5392 | 1.0817 | 2.7600 |
| Example 2 | Three Phase | Star | 415.00 | 18.00 | 0.86 | 94.00 | 11.1270 | 6.6024 | 12.9384 |
| Example 3 | Three Phase | Delta | 480.00 | 25.00 | 0.88 | 97.00 | 18.2905 | 9.8721 | 20.7846 |
Formula Used
S = (V × I) / 1000
S = (√3 × VL × IL) / 1000
P = S × PF
Q = S × sin(φ), where φ = cos-1(PF)
Pout = P × η
Loss = P - Pout
E = P × t
Z = Vphase / Iphase
R = Z × PF
X = Z × sin(φ)
Qc = P × [tan(φ1) - tan(φ2)]
How to Use This Calculator
- Select whether your load is single phase or three phase.
- Choose the connection model. Star and delta mainly affect phase values.
- Enter voltage, current, power factor, efficiency, frequency, and operating hours.
- Choose leading or lagging to set the reactive power sign correctly.
- Enter a target power factor to estimate correction kVAR and reduced current.
- Press Calculate AC Power to show results above the form.
- Use the CSV and PDF buttons to export the calculated result table.
Frequently Asked Questions
1) What is the difference between real, reactive, and apparent power?
Real power performs useful work in kilowatts. Reactive power supports magnetic or electric fields in kVAR. Apparent power combines both effects in kVA and reflects total source demand.
2) When should I choose single phase or three phase?
Choose single phase for common residential or light equipment circuits. Choose three phase for industrial motors, larger drives, and balanced distribution systems using line voltage and line current.
3) Why does leading power factor show negative reactive power?
Leading power factor means the current leads voltage, often with capacitive behavior. Engineers often mark that reactive component as negative to distinguish it from lagging inductive demand.
4) What does efficiency change in this calculator?
Efficiency adjusts output power and losses. Electrical input power is calculated from apparent power and power factor, then reduced by efficiency to estimate delivered output and waste.
5) How is target power factor used?
The target value estimates how much reactive compensation is needed for a lagging load. It also recalculates apparent power and current after improvement, which helps equipment sizing.
6) Are these results valid for unbalanced three phase loads?
No. The three phase model assumes a balanced system. For unbalanced networks, each phase should be analyzed separately because current, impedance, and phase angles may differ.
7) Should I enter line voltage for three phase systems?
Yes. For three phase calculations, enter line voltage and line current. The calculator converts them to phase values based on star or delta connection for impedance estimates.
8) Why does the chart compare magnitudes?
The graph highlights relative size for real, reactive, apparent, and output power. Magnitude comparison is clearer visually, while the result table preserves the reactive sign direction.