Voltage Line Loss Calculator

Voltage Drop Formula:

\[ Voltage\ Drop = I \times R \times L \times \sqrt{3} \ (3\text{-phase}) \]

Voltage Drop (V):

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1. What is Voltage Line Loss?

Voltage line loss refers to the reduction in voltage that occurs when electrical current flows through conductors over a distance. This phenomenon is caused by the inherent resistance of the conductors and is an important consideration in electrical system design and analysis.

2. How Does the Calculator Work?

The calculator uses the 3-phase voltage drop formula:

\[ Voltage\ Drop = I \times R \times L \times \sqrt{3} \]

Where:

\( I \) — Current in amperes (A)
\( R \) — Resistance per kilometer in ohms/km
\( L \) — Length of the conductor in kilometers (km)
\( \sqrt{3} \) — Three-phase system factor (approximately 1.732)

Explanation: The formula calculates the voltage drop in a three-phase electrical system by multiplying current, resistance per unit length, total length, and the square root of 3 factor that accounts for three-phase power distribution.

3. Importance of Voltage Drop Calculation

Details: Accurate voltage drop calculation is crucial for ensuring proper equipment operation, maintaining power quality, complying with electrical codes, and optimizing electrical system efficiency. Excessive voltage drop can lead to equipment malfunction, reduced performance, and increased energy losses.

4. Using the Calculator

Tips: Enter current in amperes, resistance per kilometer in ohms/km, and length in kilometers. All values must be positive numbers. For single-phase systems, use the appropriate single-phase voltage drop formula instead.

5. Frequently Asked Questions (FAQ)

Q1: What is considered an acceptable voltage drop?
A: Generally, voltage drop should not exceed 3% for feeders and 5% for branch circuits according to most electrical codes, but specific requirements may vary by application and local regulations.

Q2: How does conductor size affect voltage drop?
A: Larger conductor sizes have lower resistance per unit length, resulting in reduced voltage drop for the same current and distance.

Q3: What is the difference between single-phase and three-phase voltage drop?
A: Three-phase systems use the √3 factor (approximately 1.732) in calculations, while single-phase systems use a factor of 2 for the same power delivery.

Q4: How does temperature affect voltage drop calculations?
A: Conductor resistance increases with temperature, which can increase voltage drop. Calculations should account for expected operating temperatures.

Q5: When should I be concerned about voltage drop?
A: Voltage drop becomes significant in long cable runs, high-current applications, and systems with sensitive electronic equipment that requires stable voltage levels.