Wiring and Protection
Wire Power Loss Calculator
Estimate wire loss with Wire Power Loss. The page keeps the formula, assumptions, and example values visible.
Enter values for wire loss
Use one consistent electrical operating case for all fields.
How Wire Power Loss works
The governing expression is Ploss = I²R. Wire Power Loss uses Current, Circuit resistance to report Wire loss.
With the loaded values, wire loss evaluates to 100.00 W. Vary one measured quantity so the source of the difference stays clear.
Inputs for Wire Power Loss
Current and Circuit resistance belong to Wire Power Loss. Keep source units with current.
Sample entries show the formula in use. They are not substitute ratings for selected equipment.
- Current
- Example entry: 20 A.
- Circuit resistance
- Example entry: 0.25 Ω.
Reading the Wire Power Loss result
This output represents Wire Power Loss.
Keep the calculated requirement separate from the rating ultimately selected.
Measurement and units
Treat these results as planning arithmetic; conductor and protective-device selection must follow the applicable electrical code and equipment instructions. Check prefixes on current.
A fair comparison keeps units, measurement point, and operating condition consistent.
Limits of this calculation
Use the complete energized current path.
The calculation focuses on the named relationship and its entered variables. Unentered effects remain outside Wire Power Loss.
A useful Wire Power Loss comparison
Record wire loss before testing a different current value. For bundled ampacity, use Bundled Cable Derating Calculator.
Document the alternate current source.
Wire Power Loss record notes
Record source and operating details for current.
Retain raw wire loss beside its selected rating.
Questions about Wire Power Loss
What does Wire Power Loss calculate?
Wire Power Loss reports wire loss.
Can Current be zero?
For Wire Power Loss, measure any zero current directly.