1. What is Voltage Drop?

Voltage drop is the reduction in voltage in an electrical circuit between the source and load. In LED applications, excessive voltage drop can lead to dimming or non-functioning LEDs.

2. How Does the Calculator Work?

The calculator uses the voltage drop equation:

Where:

• \( VD \) — Voltage drop (volts)
• \( L \) — Length of wire (meters)
• \( I \) — Current (amperes)
• \( \rho \) — Resistivity of conductor material (Ω·m)
• \( A \) — Cross-sectional area of wire (m²)

Explanation: The equation calculates the voltage lost due to the resistance of the wire over a specific length carrying a certain current.

3. Importance of Voltage Drop Calculation

Details: Proper voltage drop calculation ensures LEDs receive adequate voltage for optimal performance and prevents excessive power loss in wiring.

4. Using the Calculator

Tips: Enter all values in the correct units. For copper wire, resistivity is typically 1.68 × 10⁻⁸ Ω·m. Wire area can be calculated from AWG or mm² measurements.

5. Frequently Asked Questions (FAQ)

Q1: What is acceptable voltage drop for LEDs?
A: Generally, voltage drop should be less than 3% of source voltage for optimal LED performance.

Q2: Why multiply length by 2?
A: The factor of 2 accounts for both the supply and return paths in DC circuits.

Q3: How does wire size affect voltage drop?
A: Larger wire (greater cross-sectional area) reduces voltage drop for a given current and length.

Q4: What resistivity value should I use for copper?
A: Pure copper at 20°C has ρ ≈ 1.68 × 10⁻⁸ Ω·m. Aluminum is about 1.6 times higher.

Q5: How does temperature affect voltage drop?
A: Higher temperatures increase resistivity, leading to greater voltage drop for the same current.