Wire Size & Voltage Drop Planner

What Is the Wire Size & Voltage Drop Planner?

The Wire Size & Voltage Drop Planner compares conductor candidates from a reviewed ampacity table and a separate resistance-based voltage-drop model. It exposes material, insulation and termination temperature assumptions, current-carrying conductor adjustments, route length, power system, ambient conditions, conductor count and operating-cost estimates instead of hiding them in one recommendation.

How It Works

Enter the design current, system voltage and one-way route length, then choose the material and allowed temperature columns. Review the ampacity, terminal, small-conductor and voltage-drop screens separately. Treat the first passing row as a planning candidate only, inspect alternatives and export the assumptions for qualified review.

When to Use It

Use it to compare early conductor options or understand which constraint drives a candidate size. Final conductor, raceway, overcurrent protection, derating, grounding and installation decisions require the adopted code, manufacturer data and a qualified electrical professional.

Frequently Asked Questions

Does The Smallest Passing Row Guarantee A Valid Installation?

No. The planner covers only its stated screens. Equipment listings, terminal ratings, conductor type, bundling, ambient conditions, raceway fill, voltage-drop goals and local rules can require a different result.

Why Are Ampacity And Voltage Drop Separate?

Ampacity limits conductor heating under stated conditions; voltage drop estimates circuit performance. A conductor can pass one screen and fail the other.

Is Aluminum The Same As Copper-Clad Aluminum?

No. The table and interface identify copper-clad aluminum where a value does not apply to plain aluminum, including the smallest listed size.

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