How Solar Cable Voltage Drop Calculator Works
Estimate DC voltage drop in a two-wire solar cable run from current, cable length, conductor resistance and system voltage. The calculation runs locally in your browser and does not require an account.
How to use it
- Enter values using the units shown.
- Check your source measurements and assumptions.
- Calculate and compare scenarios before making a decision.
Limitations
Solar Cable Voltage Drop Calculator is an estimation aid. For a critical result, compare the inputs and output with the applicable standard, manufacturer data, project specification, site condition, or qualified professional review.
Solar cable voltage drop
Voltage drop occurs because every conductor has electrical resistance. In a DC solar circuit the current travels out to the load and returns through the second conductor, so the calculation uses the two-way cable length. Even a modest voltage drop can become significant in low-voltage systems carrying substantial current.
Conductor resistance changes with temperature and conductor material, and installation conditions can affect the result. Use the actual cable datasheet resistance where available. For a complete photovoltaic design, also consider current-carrying capacity, protection, connector ratings, installation method and applicable electrical requirements. The calculator is not a substitute for a compliant system design.