1. What is Terminal Voltage?

Definition: Terminal voltage is the actual voltage available at the output terminals of a generator when current is being drawn.

Purpose: This calculator helps determine the working voltage of a generator under load, which is crucial for electrical system design and troubleshooting.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( V_t \) — Terminal voltage (Volts, V)
• \( E \) — EMF (Volts, V)
• \( I \) — Current (Amperes, A)
• \( R \) — Internal resistance (Ohms, Ω)

Explanation: The voltage drops across the internal resistance when current flows, reducing the available terminal voltage below the EMF.

3. Importance of Terminal Voltage Calculation

Details: Proper terminal voltage calculation ensures electrical devices receive the correct operating voltage and helps diagnose generator performance issues.

4. Using the Calculator

Tips: Enter the generator's EMF (open-circuit voltage), the current being drawn, and the generator's internal resistance. All values must be ≥ 0.

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between EMF and terminal voltage?
A: EMF is the voltage when no current flows (open circuit), while terminal voltage is the actual voltage under load.

Q2: Why does terminal voltage decrease with increasing current?
A: The voltage drop across internal resistance (I×R) increases with current, reducing the available terminal voltage.

Q3: What's a typical internal resistance for generators?
A: This varies by generator size and type, but small generators might have 0.1-0.5Ω, while large ones may have 0.01-0.1Ω.

Q4: Can terminal voltage ever be higher than EMF?
A: No, in normal operation terminal voltage is always less than or equal to EMF.

Q5: How does this relate to voltage regulation?
A: Voltage regulation percentage is calculated as (EMF - Terminal Voltage)/Terminal Voltage × 100%.