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Eecol Electric Voltage Drop Calculator

Voltage Drop Formula:

\[ VD = \frac{2 \times I \times L \times R}{1000} \]

amps
meters
ohms/km
volts

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1. What is Voltage Drop Calculation?

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

\[ VD = \frac{2 \times I \times L \times R}{1000} \]

Where:

Explanation: The formula accounts for both the outgoing and return paths (hence the 2× factor) in a single-phase system.

3. Importance of Voltage Drop Calculation

Details: Proper voltage drop estimation ensures electrical equipment receives adequate voltage and prevents performance issues or safety hazards.

4. Using the Calculator

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

5. Frequently Asked Questions (FAQ)

Q1: Why multiply by 2 in the formula?
A: The factor of 2 accounts for both the supply and return conductors in a single-phase circuit.

Q2: What's a typical acceptable voltage drop?
A: Most standards recommend less than 3% voltage drop for branch circuits and 5% for feeders.

Q3: How do I find conductor resistance?
A: Resistance values are typically provided in cable specifications or electrical reference tables.

Q4: Does this work for three-phase systems?
A: This formula is for single-phase. Three-phase systems use \( \sqrt{3} \) instead of 2.

Q5: What affects conductor resistance?
A: Resistance depends on material (copper/aluminum), cross-sectional area, temperature, and frequency.

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