Table
Voltage Drop Sensitivity by Current and Distance
Voltage Drop Sensitivity by Current and Distance lookup table with assumptions and boundary notes.
Scope
Relationship planning only. It does not determine whether a circuit result is acceptable.
Lookup table
See how voltage drop changes when current, distance, voltage, or conductor resistance changes.
Scroll sideways to keep row labels aligned with hidden columns.
| Change | Voltage-drop effect | Why | Example |
|---|---|---|---|
| Current doubles | Volts dropped doubles | Current is a direct multiplier | 20 A to 40 A doubles the estimated drop |
| One-way distance doubles | Volts dropped doubles | Length is a direct multiplier | 30 m to 60 m doubles conductor resistance in the path |
| Conductor area doubles | Volts dropped is roughly halved | Resistance is inversely related to area | Larger conductors reduce resistance |
| Nominal voltage doubles | Percent drop is roughly halved | Same volt drop divided by higher voltage | 6 V drop is 5 percent at 120 V and 2.5 percent at 240 V |
Notes
- Check table values for preliminary lookup and arithmetic checks only.
- Confirm equipment ratings, product markings, installation conditions, utility requirements, and the local authority requirements before design or field use.