1. What is Voltage Drop Calculation?

The voltage drop calculation determines the reduction in voltage in an electrical circuit due to the resistance of the conductors. For parallel battery runs, it helps ensure proper system performance by accounting for multiple current paths.

2. How Does the Calculator Work?

The calculator uses the voltage drop equation:

Where:

• \( VD \) — Voltage drop (%)
• \( I \) — Current (amperes)
• \( n \) — Number of parallel runs
• \( L \) — Length of conductor (feet)
• \( R \) — Resistance per unit length (ohms/ft)
• \( V \) — System voltage (volts)

Explanation: The equation accounts for current divided among parallel conductors, with voltage drop proportional to conductor length and resistance.

3. Importance of Voltage Drop Calculation

Details: Proper voltage drop calculation ensures electrical systems operate efficiently, prevents excessive power loss, and maintains equipment performance within specifications.

4. Using the Calculator

Tips: Enter current in amperes, number of parallel runs, conductor length in feet, resistance in ohms per foot, and system voltage. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is an acceptable voltage drop?
A: Typically 3% or less for branch circuits, 5% or less for feeders, but consult local electrical codes.

Q2: How does parallel runs affect voltage drop?
A: Multiple parallel runs reduce voltage drop by dividing the current among conductors.

Q3: Where can I find conductor resistance values?
A: Resistance values are available in NEC tables or from conductor manufacturers' specifications.

Q4: Does temperature affect the calculation?
A: Yes, resistance changes with temperature. Use resistance values appropriate for operating conditions.

Q5: Should I include connector resistance?
A: For precise calculations, include significant connection resistances in the total circuit resistance.