Using the conductor's own R and X per kilometre to find how much voltage a rural 11 kV feeder loses over 5 km of overhead line.
| Sending-end voltage | 11 kV line-to-line |
| Load current | 100 A |
| Power factor | 0.85 lagging |
| Conductor resistance | 0.4 Ω/km |
| Conductor reactance | 0.35 Ω/km |
| Line length | 5 km |
| Check | Requirement | Actual | Status |
|---|---|---|---|
| Voltage regulation | Typically ≤5% for a distribution feeder (project-specific) | 4.13% | ✓ PASS |
Key insight: Both resistance and reactance terms matter for overhead lines the way they usually don't for short LV cable runs — X is 1.75 Ω here, not far behind R's 2.0 Ω, because overhead conductors are spaced much further apart than cores in a cable, which increases per-km reactance substantially. Ignoring the reactance term (as some simplified LV-style formulas do) would understate the voltage drop on a line like this.
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Open Overhead Line Voltage Regulation calculator →This calculator deliberately doesn't embed an ACSR/AAAC/AAC conductor table, to avoid the transcription risk of hand-copying dozens of conductor geometries — R and X per km are entered from the specific conductor's own datasheet (which itself depends on conductor size, stranding and phase spacing), which is the only way to get a value that's actually correct for the real installation rather than a generic placeholder.
In this calculator they describe the same underlying number from two angles: voltage drop is the absolute loss in volts, and regulation is that same loss expressed as a percentage of the sending-end voltage — regulation is the figure usually compared against a grid code or utility limit, since a fixed volt drop matters differently at 400 V than at 33 kV.