1. What is Voltage Drop?

Voltage drop is the reduction in voltage in an electrical circuit between the source and load. It's important to calculate to ensure proper operation of electrical equipment and compliance with regulations in both UK and Australia.

2. How Does the Calculator Work?

The calculator uses the voltage drop formula:

Where:

• \( mV/A/m \) — Millivolts per amp per meter (cable characteristic)
• \( I \) — Current in amps
• \( L \) — Length of cable in meters

Explanation: The equation calculates the voltage drop based on the cable's resistance per unit length, the current flowing through it, and the total length of the run.

3. Importance of Voltage Drop Calculation

Details: Proper voltage drop calculation ensures electrical devices receive sufficient voltage to operate correctly and helps prevent overheating of cables. Both UK and Australian standards have similar requirements for maximum allowable voltage drop.

4. Using the Calculator

Tips: Enter the cable's mV/A/m value (available from manufacturer specs), the expected current in amps, and the cable length in meters. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's the typical mV/A/m for common cables?
A: For 2.5mm² PVC insulated cable it's about 18 mV/A/m, while 1.5mm² is about 29 mV/A/m (values vary by standard and manufacturer).

Q2: What's the maximum allowable voltage drop?
A: Typically 3% for lighting and 5% for other circuits in both UK and Australian standards, measured from origin to load.

Q3: Does this calculator work for both AC and DC?
A: Yes, the basic calculation is the same for both, though AC systems may need additional considerations for power factor.

Q4: Why is this calculator suitable for UK to Australia?
A: Both countries use similar voltage drop calculation methods and compatible cable standards (IEC/AS/NZS).

Q5: How does temperature affect voltage drop?
A: Higher temperatures increase cable resistance and thus voltage drop. Some standards provide correction factors.