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Calcimator

Load Flow Calculator

Calculate power flow, losses, and voltage drop through transmission lines.

Inputs

kV
A
miles
Ω/mi
Ω/mi

Results

Real Power

113,535.9 kW

Line Losses

3,750 kW

≈ 250 homes' peak draw

Reactive Power37,317.5 kVAR
Voltage Drop7.88%
Loss Percentage3.3%
How to Use This Calculator
  1. Enter Line Voltage, Line Current, and Power Factor.
  2. Set Line Length, Resistance, and Reactance.
  3. Review Real Power (kW) and Line Losses (kW).
  4. Use Reactive Power (kVAR) and Voltage Drop (%) to inform your decision.

How the result changes with Line Voltage

Line VoltageReal PowerLine Losses
7763,349.8 kW3,750 kW
268220,490.1 kW3,750 kW
498409,716.6 kW3,750 kW
689566,856.9 kW3,750 kW

What each input means

Line Voltage
Line-to-line voltage of the transmission line.
Line Current
Current flowing through the line.
Power Factor
Load power factor (lagging).
Line Length
Length of the transmission line.
Resistance
Line resistance per mile.
Reactance
Line reactance per mile.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Line Voltage = 138, Line Current = 500, Power Factor = 0.95, Line Length = 50 = 6 input(s) provided
  2. Calculate Real Power
    Real Power
    113535.9 = 113535.9
  3. Calculate Line Losses
    Line Losses
    3750 = 3750
  4. Calculate Reactive Power
    Reactive Power
    37317.5 = 37317.5
  5. Calculate Voltage Drop
    Voltage Drop
    7.88 = 7.88

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