Cable assessment
Preliminary cable sizing with custom engineering data
Evaluate your own cable candidates against ampacity, correction-factor and voltage-drop checks.
Open preliminary cable-size calculator →
What this calculation is for
This tool sorts the cable candidates you supply and shows each candidate’s pass or fail state. It deliberately uses custom or demo data and labels results Review required; it does not embed licensed standards tables or make a compliance decision.
How to use the calculator
- Enter design current and your selected voltage-drop target.
- Add or import traceable cable, ampacity and correction-factor data.
- Check the composed correction factor and each candidate’s corrected ampacity and drop result.
- Select only a candidate that has been independently reviewed for the installation and governing requirements.
Useful for
- • Comparing a controlled set of candidate cables
- • Recording assumptions in a local project
- • Showing which preliminary constraint governs a choice
Fields explained
Design current (Ib)
Expected load current used for the preliminary assessment.
Base ampacity
A value from your own traceable cable dataset.
Correction factors
User-supplied factors applied to base ampacity.
Cable data
Resistance, reactance or mV/A/m values used for voltage-drop checking.
Thermal short-circuit check
Optional and only usable with appropriate verified input data.
Important limits and next checks
Preliminary engineering aid only. This article and its calculator do not provide an approval, certificate, compliance determination or installation instruction.
- A passing custom-data check is not approval, certification or a construction instruction.
- Obtain suitable professional review, manufacturer information and local-rule checks before procurement.
Verify applicable laws, rules, standards, manufacturer data and project conditions with a qualified electrical professional before construction, procurement or regulatory submission.