1. What is the Overhead Voltage Drop Equation?

The Overhead Voltage Drop equation calculates the percentage of voltage lost in an overhead electrical distribution system due to the resistance of the conductors. It helps electrical engineers ensure proper voltage levels at the load end.

2. How Does the Calculator Work?

The calculator uses the Overhead Voltage Drop equation:

Where:

• \( VD \) — Voltage drop (%)
• \( I \) — Current (amperes)
• \( L \) — Length of conductor (feet)
• \( R_{overhead} \) — Resistance per foot (ohms/ft)
• \( V \) — Voltage (volts)

Explanation: The equation calculates the percentage of voltage lost based on the current flow, conductor length, resistance, and system voltage.

3. Importance of Voltage Drop Calculation

Details: Proper voltage drop calculation ensures electrical equipment receives adequate voltage for proper operation and helps prevent power quality issues.

4. Using the Calculator

Tips: Enter current in amperes, length in feet, resistance in ohms per foot, and system voltage in volts. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is an acceptable voltage drop?
A: Typically 3% for branch circuits and 5% for feeder and branch circuits combined, but consult local codes.

Q2: How does conductor size affect voltage drop?
A: Larger conductors have lower resistance, resulting in less voltage drop for the same current and distance.

Q3: Why calculate voltage drop for overhead lines?
A: Overhead lines often span long distances where voltage drop can be significant, affecting end-user equipment.

Q4: Does temperature affect the calculation?
A: Yes, conductor resistance changes with temperature, but this calculator uses resistance at operating temperature.

Q5: Should I consider single-phase or three-phase systems differently?
A: Yes, three-phase calculations differ. This calculator is for single-phase overhead systems.