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Area of X-Section(DC 3-Wire) Calculator

Formula Used:

\[ A = \frac{2 \times I^2 \times \rho \times L}{P_{loss}} \]

A
Ω·m
m
W

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1. What is Area of X-Section Calculation?

The Area of X-Section calculation determines the cross-sectional area of a DC 3-wire overhead transmission line based on current, resistivity, length, and acceptable power losses. This is crucial for proper wire sizing in electrical distribution systems.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ A = \frac{2 \times I^2 \times \rho \times L}{P_{loss}} \]

Where:

Explanation: The formula calculates the minimum cross-sectional area required to maintain specified power losses for a given current flow through a conductor of specific length and material properties.

3. Importance of Cross-Sectional Area

Details: Proper wire sizing ensures efficient power transmission, prevents excessive voltage drop, minimizes power losses, and ensures the system operates within safe temperature limits to prevent overheating and potential fire hazards.

4. Using the Calculator

Tips: Enter current in amperes, resistivity in ohm-meters, length in meters, and line losses in watts. All values must be positive numbers greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: Why is the factor 2 used in the formula?
A: The factor 2 accounts for the return path in DC 3-wire systems where current flows through both the outgoing and return conductors.

Q2: What is typical resistivity for copper wire?
A: Copper has a resistivity of approximately 1.68 × 10⁻⁸ Ω·m at 20°C, while aluminum is about 2.82 × 10⁻⁸ Ω·m.

Q3: How does temperature affect the calculation?
A: Resistivity increases with temperature, so calculations should use resistivity values at the expected operating temperature for accuracy.

Q4: What are acceptable power loss percentages?
A: Typically, power losses are kept below 2-5% of the total transmitted power for efficient operation, though this varies by application.

Q5: Can this calculator be used for AC systems?
A: No, this formula is specifically for DC systems. AC systems require additional considerations for skin effect and proximity effect.

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