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Advanced electrical check

Separate DC and AC wire calculator

Calculate DC and AC conductors independently because circuit voltage, current, phase geometry, and acceptable losses are different.

No account Instant result Explanation included
1Tell us what you knowStart with the fields you already understand.
2See the recommendationSee the number and why Solar Plan Lab suggested it.
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Independent circuit worksheet

Inputs

i
Use the actual nominal circuit voltage. Example: 51.2 V for a 48 V-class LiFePO4 battery bus, or the calculated operating voltage of a PV string.
i
Maximum expected direct current through the conductor. Use the array current, battery current, or equipment output current.
i
Distance from the DC source to the DC equipment. The calculator automatically includes the outgoing and return conductors.
i
Copper has lower resistance for the same cross-sectional area. Aluminium normally requires a larger conductor.
i
Maximum acceptable DC voltage loss. Low-voltage battery circuits are especially sensitive because even a small voltage loss can be significant.
Visual aid

Cable voltage-drop visual

SOURCE
Energy travelling through cable
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DC calculation

Uses entered DC voltage and DC current and includes both outgoing and return conductors.

AC calculation

Calculates current from load power, AC voltage, phase type, and power factor before sizing the conductor.

Example

Example calculation

Solar Plan Lab uses the current project values to show how the recommendation changes.

Common mistake

Do not rely on one number alone

Check the result against actual equipment and site conditions.

Frequently asked

Is this installation-ready?

No. It is a planning estimate that should be verified by qualified professionals.

How was this calculated?

Calculation method

Formula

The calculator uses the displayed inputs and standard planning relationships.

Important assumptions

Verify the final design against actual equipment data sheets, site conditions, and applicable requirements.

Read the full methodology and update history →
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