Calculators Grid
Concrete & Masonry
Roofing & Framing
Design & Finishes
Mechanical & Solar
Metric Units

Glossary: Voltage Drop

**Voltage Drop** is the decrease in electrical potential along the path of a current flowing through an electrical circuit, caused by the resistance of the conductor wires.

Electrical Resistance & Safety

The National Electrical Code (NEC) recommends keeping voltage drop under 3% for branch circuits and 5% total (including feeder lines) to prevent motor overheating and efficiency loss.

Related Active Calculator:

⚡ Voltage Drop Calculator