1. What is a Voltage Drop Calculator?

Definition: This calculator estimates the voltage drop in an electrical circuit based on current, cable length, and conductor resistance.

Purpose: It helps electricians and engineers ensure proper voltage levels throughout electrical installations.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( VD \) — Voltage drop (volts)
• \( I \) — Current (amps)
• \( L \) — Length of cable (meters)
• \( R \) — Conductor resistance (ohms/km)

Explanation: The factor of 2 accounts for the round-trip path of the circuit (both supply and return conductors).

3. Importance of Voltage Drop Calculation

Details: Proper voltage drop calculation ensures electrical equipment receives adequate voltage for optimal performance and prevents excessive power loss.

4. Using the Calculator

Tips: Enter the current in amps, cable length in meters, and conductor resistance in ohms per kilometer. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why is voltage drop important?
A: Excessive voltage drop can cause equipment malfunction, reduced efficiency, and potential safety hazards.

Q2: What's an acceptable voltage drop?
A: Typically 3% for lighting circuits and 5% for other circuits, but check local electrical codes.

Q3: How do I find conductor resistance?
A: Consult cable manufacturer specifications or standard resistance tables for common conductor sizes.

Q4: Does this work for both AC and DC circuits?
A: This formula works for DC circuits. For AC circuits, impedance should be used instead of resistance.

Q5: What if I have a single-phase vs three-phase system?
A: This calculator is for single-phase systems. Three-phase calculations require a different formula.