1. What is Voltage Drop?

Definition: Voltage drop is the reduction in voltage in an electrical circuit between the source and load.

Purpose: Calculating voltage drop helps ensure proper operation of electrical devices and compliance with electrical codes.

2. How Does the Voltage Drop Formula Work?

The calculator uses Ohm's Law formula:

Where:

• \( VD \) — Voltage drop (volts)
• \( I \) — Current flowing through the circuit (amps)
• \( R \) — Resistance of the conductor (ohms)

Explanation: The voltage drop is directly proportional to both the current and the resistance in the circuit.

3. Importance of Voltage Drop Calculation

Details: Proper voltage drop calculation ensures electrical devices receive adequate voltage, prevents overheating, and maintains energy efficiency.

4. Using the Calculator

Tips: Enter the current in amps and the resistance in ohms. Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's an acceptable voltage drop?
A: Typically 3% for branch circuits and 5% for feeder and branch circuits combined (NEC recommendations).

Q2: How do I find the resistance of a wire?
A: Use the wire's resistivity (Ω/m or Ω/ft) multiplied by its length. Resistance tables are available for standard wire gauges.

Q3: Does voltage drop affect power consumption?
A: Yes, voltage drop represents power lost as heat in the conductors (P = I²R).

Q4: When is voltage drop most problematic?
A: In long wire runs, high current applications, or with sensitive electronic equipment.

Q5: How can I reduce voltage drop?
A: Use larger wire (lower gauge), shorter runs, or higher voltage systems.