Voltage Drop Calculator
This is a calculator for the estimation of the voltage drop of an electrical circuit. The “NEC data” tab calculates based on the resistance and reactance data from the National Electrical Code (NEC). The “Estimated resistance” tab calculates based on the resistance data estimated from the wire size. Click the “Other” tab to use customized resistance or impedance data, such as data from other standards or wire manufacturers.
Modify the values and click the calculate button to use
Voltage Drop Calculator
The Voltage Drop Calculator is an essential tool for electricians, engineers, and DIY enthusiasts to estimate voltage loss in electrical circuits. Voltage drop occurs when electrical current flows through a conductor, causing a reduction in voltage due to resistance. Excessive voltage drop can lead to inefficient power delivery, overheating, and equipment malfunction.
Features:
✅ Three Calculation Methods:
- NEC Data – Uses resistance and reactance values from the National Electrical Code (NEC) for precise calculations.
- Estimated Resistance – Calculates based on wire size and material properties (Copper, Aluminum, Silver, Gold).
- Custom Input – Allows manual entry of resistance/impedance values for specialized applications.
✅ Flexible Input Options:
- Wire Material & Size (AWG/kcmil)
- Conduit Type (Steel, Aluminum, PVC)
- Power Factor (PF) adjustment
- Voltage & Phase Selection (AC Single-Phase, 3-Phase, or DC)
- Distance Units (Feet, Meters, Miles, Kilometers)
- Parallel Conductors (1–9 sets)
✅ Instant Results:
- Voltage Drop (V) – The amount of voltage lost.
- Voltage Drop (%) – Percentage loss relative to supply voltage.
- Voltage at Load End – Remaining voltage after drop.
Why Use This Calculator?
✔ Ensures safe and efficient electrical installations.
✔ Helps comply with NEC standards (max 3% drop for branch circuits, 5% for feeders).
✔ Prevents dim lighting, motor failures, and overheating.
✔ Suitable for residential, commercial, and industrial applications.
Note: Results are estimates. Actual voltage drop may vary due to temperature, frequency, and wire condition. Always consult electrical codes and professionals for critical installations.
🔌 Try it now to optimize your circuit design! ⚡